| 1. |
- Augustinsson (Nilsdotter-Augustinsson), Åsa, 1962-, et al.
(författare)
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Interaction of staphylococcus epidermidis from infected hip prostheses with neutrophil granulocytes
- 2001
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Ingår i: Scandinavian Journal of Infectious Diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 33:6, s. 408-412
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Tidskriftsartikel (refereegranskat)abstract
- This study focuses on the interaction of Staphylococcus epidermis isolated from granulation tissue covering infected hip prostheses and neutrophil granulocytes. Bacterial strains isolated from normal flora were used as controls. The bacteria were well characterized with routine methods and further characterized with random amplified polymorphic DNA analyses and slime tests. Phagocytosis and chemiluminescence (CL) assays were used in the neutrophil interaction studies. The prostheses strains were ingested to a lesser extent than strains from normal flora (p ≤ 0.001). There was no significant difference between the prostheses strains and the normal flora strains in terms of total CL response. However, the extracellular CL response from the neutrophils was lower in comparison with the normal flora when interacting with the prostheses strains. The results of this study support the notion that S. epidermidis strains isolated from infected hip prostheses have an enhanced capacity to resist phagocytosis and that most of these strains elicit a reduced inflammatory response, measured as the production of extracellular oxidative metabolites from the neutrophils, compared to normal flora.
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| 2. |
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| 3. |
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| 4. |
- Nilsdotter-Augustinsson, Åsa, 1962-, et al.
(författare)
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Staphylococcus aureus, but not Staphylococcus epidermidis, modulates the oxidative response and induces apoptosis in human neutrophils
- 2004
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley. - 0903-4641 .- 1600-0463. ; 112:2, s. 109-118
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Tidskriftsartikel (refereegranskat)abstract
- S. epidermidis is the most common isolate in foreign body infections. The aim of this study was to understand why S. epidermidis causes silent biomaterial infections. In view of the divergent inflammatory responses S. epidermidis and S. aureus cause in patients, we analyzed how they differ when interacting with human neutrophils. Neutrophils interacting with S. epidermidis strains isolated either from granulation tissue covering infected hip prostheses or from normal skin flora were tested by measuring the oxidative response as chemiluminescence and apoptosis as annexin V binding. Different S. aureus strains were tested in parallel. All S. epidermidis tested were unable to modulate the oxidative reaction in response to formyl-methionyl-leucyl-phenylalanine (fMLP) and did not provoke, but rather inhibited, apoptosis. In contrast, some S. aureus strains enhanced the oxidative reaction, and this priming capacity was linked to p38-mitogen-activated-protein-kinase (p38-MAPK) activation and induction of apoptosis. Our results may explain why S. epidermidis is a weak inducer of inflammation compared to S. aureus, and therefore responsible for the indolent and chronic course of S. epidermidis biomaterial infections.
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| 5. |
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| 6. |
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| 7. |
- Wilsson, Åsa, et al.
(författare)
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Apoptotic neutrophils containing Staphylococcus epidermidis stimulate macrophages to release the proinflammatory cytokines tumor necrosis factor-a and interleukin-6
- 2008
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Ingår i: FEMS Immunology and Medical Microbiology. - : Oxford University Press. - 0928-8244 .- 1574-695X. ; 53:1, s. 126-135
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Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus epidermidis infections are usually nosocomial and involve colonization of biomaterials. The immune defense system cannot efficiently control the bacteria during these infections, which often results in protracted chronic inflammation, in which a key event is disturbed removal of neutrophils by tissue macrophages. While ingesting uninfected apoptotic neutrophils, macrophages release anti-inflammatory cytokines that lead to resolution of inflammation. In clinical studies, we have previously found elevated levels of the proinflammatory cytokines tumor necrosis factor-alpha (TNF-a) and interleukin-6 in synovial fluid from prostheses infected with coagulase negative staphylococci. We show that macrophages phagocytosing apoptotic neutrophils containing S. epidermidis released TNF-a and interleukin-6, whereas macrophages phagocytosing spontaneously apoptotic neutrophils did not. This difference was not due to dissimilar phagocytic capacities, because macrophages ingested both types of neutrophils to the same extent. The activation was induced mainly by the apoptotic neutrophils themselves, not by the few remaining extracellular bacteria. Macrophages were not activated by apoptotic neutrophils that contained paraformaldehyde-killed S. epidermidis. Proinflammatory reactions induced by clearance of apoptotic neutrophils containing S. epidermidis might represent an important mechanism to combat the infective agent. This activation of macrophages may contribute to the development of chronic inflammation instead of inflammation resolution. © 2008 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.
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| 8. |
- Enocsson, Helena, et al.
(författare)
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Soluble Urokinase Plasminogen Activator Receptor (suPAR) Independently Predicts Severity and Length of Hospitalisation in Patients With COVID-19
- 2021
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Ingår i: Frontiers in Medicine. - : Frontiers Media SA. - 2296-858X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background: Efficient healthcare based on prognostic variables in hospitalised patients with COVID-19 could reduce the risk of complications and death. Recently, soluble urokinase Plasminogen Activator Receptor (suPAR) was shown to predict respiratory failure, kidney injury, and clinical outcome in patients with SARS-CoV-2 infection. The aim of this study was to investigate the value of suPAR as a prognostic tool, in comparison with other variables, regarding disease severity and length of hospital stay in patients with COVID-19.Patients and Methods: Individuals hospitalised with COVID-19 (40 males, 20 females; median age 57.5 years) with a median symptom duration of 10 days and matched, healthy controls (n = 30) were included. Admission levels of suPAR were measured in serum by enzyme-linked immunosorbent assay. Blood cell counts, C-reactive protein (CRP) levels, lactate dehydrogenase (LDH), plasma creatinine and estimated glomerular filtration rates were analysed and oxygen demand, level of care and length of hospitalisation recorded.Results: Patients had significantly higher suPAR levels compared to controls (P < 0.001). Levels were higher in severely/critically (median 6.6 ng/mL) compared with moderately ill patients (median 5.0 ng/mL; P = 0.002). In addition, suPAR levels correlated with length of hospitalisation (rho = 0.35; P = 0.006). Besides suPAR, LDH, CRP, neutrophil count, neutrophil-to-monocyte and neutrophil-to-lymphocyte ratio, body mass index and chronic renal failure were discriminators of COVID-19 severity and/or predictors of length of hospitalisation.Conclusion: Admission levels of suPAR were higher in patients who developed severe/critical COVID-19 and associated with length of hospital stay. In addition, we showed that suPAR functioned as an independent predictor of COVID-19 disease severity.
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| 9. |
- Govender, Melissa, et al.
(författare)
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T cell perturbations persist for at least 6 months following hospitalization for COVID-19
- 2022
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- COVID-19 is being extensively studied, and much remains unknown regarding the long-term consequences of the disease on immune cells. The different arms of the immune system are interlinked, with humoral responses and the production of high-affinity antibodies being largely dependent on T cell immunity. Here, we longitudinally explored the effect COVID-19 has on T cell populations and the virus-specific T cells, as well as neutralizing antibody responses, for 6-7 months following hospitalization. The CD8(+) TEMRA and exhausted CD57(+) CD8(+) T cells were markedly affected with elevated levels that lasted long into convalescence. Further, markers associated with T cell activation were upregulated at inclusion, and in the case of CD69(+) CD4(+) T cells this lasted all through the study duration. The levels of T cells expressing negative immune checkpoint molecules were increased in COVID-19 patients and sustained for a prolonged duration following recovery. Within 2-3 weeks after symptom onset, all COVID-19 patients developed anti-nucleocapsid IgG and spike-neutralizing IgG as well as SARS-CoV-2-specific T cell responses. In addition, we found alterations in follicular T helper (TFH) cell populations, such as enhanced TFH-TH2 following recovery from COVID-19. Our study revealed significant and long-term alterations in T cell populations and key events associated with COVID-19 pathogenesis.
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| 10. |
- Hagbom, Marie, et al.
(författare)
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Evaluation of SARS-CoV-2 rapid antigen diagnostic tests for saliva samples
- 2022
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Ingår i: Heliyon. - : Elsevier Science Ltd. - 2405-8440. ; 8:2
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Tidskriftsartikel (refereegranskat)abstract
- Using saliva samples would facilitate sample collection, diagnostic feasibility, and mass screening of SARS-CoV-2. We tested two rapid antigen (RAD) immunochromatographic tests designed for detection of SARS-CoV-2 in saliva: Rapid Response (TM) COVID-19 Antigen Rapid Test Cassette for oral fluids and DIAGNOS (TM) COVID-19 Antigen Saliva Test. Evaluation of detection limit was performed with purified SARS-CoV-2 nucleocapsid protein and live SARSCoV-2 virus. Sensitivity and specificity were further evaluated with reverse transcription quantitative PCR (RTqPCR) positive and negative saliva samples from hospitalized individuals with COVID-19 (n = 39) and healthcare workers (n = 20). DIAGNOS showed higher sensitivity than Rapid Response for both nucleocapsid protein and live virus. The limit of detection of the saliva test from DIAGNOS was further comparable with the Abbott Panbio (TM) COVID-19 Ag Rapid Test designed for nasopharyngeal samples. DIAGNOS and Rapid Response detected nine (50.0%) and seven (38.9%), respectively, of the 18 RT-qPCR positive saliva samples. All RT-qPCR negative saliva (n = 41) were negative with both tests. Only one of the RT-qPCR positive saliva samples contained infectious virus as determined by cell culture and was also positive using the saliva RADs. The results show that the DIAGNOS may be an important and easy-to-use saliva RAD complement to detect SARS-CoV-2 positive individuals, but validation with a larger sample set is warranted.
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| 11. |
- Hamad, Tarza, et al.
(författare)
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Antibiotic susceptibility among Staphylococcus epidermidis isolated from prosthetic joint infections, with focus on doxycycline
- 2015
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Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley-Blackwell. - 0903-4641 .- 1600-0463. ; 123:12, s. 1055-1060
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, coagulase-negative staphylococci such as Staphylococcus epidermidis have gained importance as nosocomial pathogens, especially in immunocompromised patients and prosthetic joint infections (PJIs). These infections are often long lasting and difficult to treat due to the production of bacterial biofilm and the transformation of the bacteria into a stationary growth phase. Rifampicin is able to penetrate the biofilm, but to reduce the risk of development of rifampicin resistance it should be used in combination with an additional antibiotic. In this study we used Etest to investigate the antimicrobial susceptibility of 134 clinical isolates of S.epidermidis obtained from PJIs to six oral antibiotics: doxycycline, rifampicin, linezolid, fusidic acid, clindamycin, and ciprofloxacin. We also performed synergy testing on doxycycline in combination with each of the remaining antibiotics. Ninety-three (69%) of the 134 isolates were susceptible to doxycycline, 94/134 (70%) to rifampicin, 56/134 (42%) to clindamycin, 25/134 (19%) to ciprofloxacin, 81/134 (60%) to fusidic acid, and 100% to linezolid. Thirty-two (80%) of the 40 isolates not fully susceptible to rifampicin were susceptible to doxycycline. Doxycycline in combination with each of the other investigated antibiotics exerted an additive effect on nearly half of the isolates, with the exception of clindamycin, which displayed an even higher percentage of additive effect (69%). To conclude, as the majority of the S.epidermidis isolates were susceptible to doxycycline, this antimicrobial agent may provide a potential alternative for combination therapy together with rifampicin.
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| 12. |
- Hellmark, Bengt, et al.
(författare)
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Antibiotic susceptibility among Staphylococcus epidermidis isolated from prosthetic joint infections with special focus on rifampicin and variability of the rpoB gene
- 2009
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Ingår i: CLINICAL MICROBIOLOGY AND INFECTION. - Oxford : Elsevier BV. - 1198-743X .- 1469-0691. ; 15:3, s. 238-244
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Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus epidermidis is the most important pathogen in infections related to implanted foreign materials, especially prosthetic joint infections (PJIs). The aim of this study was to investigate the antimicrobial activities of 16 antibiotics against S. epidermidis isolated from PJIs, with special focus on rifampicin and rpoB variability. Ninety-one per cent of the isolates were multiresistant (i.e. resistant to members of more than three classes of antibiotics). Thirty-nine per cent were resistant to rifampicin, associated with one or two single-nucleotide polymorphisms (SNPs) in rpoB. Using IsoSensitest agar with supplements, 61% were resistant to oxacillin, and using Mueller-Hinton II agar with supplement, 84% were resistant. Using the Etest, 58% were resistant to cefoxitin, and using the disk diffusion test, 91% were resistant. The mecA gene was detected in 85% of the isolates. Regarding recently available antibiotics, all isolates were susceptible to tigecycline and linezolid, and 97% were susceptible to daptomycin. In addition, two novel antibiotics, dalbavancin and ceftobiprole, were tested, although not yet available for routine use. The MIC50 and MIC90 values of these novel antibiotics were 0.032 and 0.047 mg/L and 0.5 and 1.5 mg/L, respectively. Among the other antibiotics, the rates of resistance varied between 0% (vancomycin) and 82% (trimethoprim-sulphamethoxazole). S. epidermidis strains causing PJIs often show multiresistance, including resistance to rifampicin, which is mainly caused by one or two SNPs. Some of the newer antimicrobial agents may provide alternatives for monotherapy or combination therapy with rifampicin. Detection of mecA is necessary before initiating treatment of infections due to S. epidermidis when it displays intermediate susceptibility to cefoxitin.
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| 13. |
- Hellmark, Bengt, 1971-, et al.
(författare)
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Comparison of Staphylococcus epidermidis isolated from prosthetic joint infections and commensal isolates in regard to antibiotic susceptibility, agr type, biofilm production, and epidemiology
- 2013
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Ingår i: International Journal of Medical Microbiology. - Jena, Germany : Elsevier. - 1438-4221 .- 1618-0607. ; 303:1, s. 32-39
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Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus epidermidis is the predominant bacterial species in the normal flora of the human skin and superficial mucosal membranes. However, it has also emerged as the most important pathogen in infections related to foreign-body materials, such as prosthetic joints and heart valves. The aims of this study were to characterise S. epidermidis isolated from prosthetic joint infections (PJI; n = 61) and commensal isolates from healthy individuals (n = 24) in regard to antimicrobial sensitivity, agr type, hid gene presence, biofllm production including presence of ica and aap genes involved in the biofilm formation process and epidemiology using both phenotypic (the PhenePlate-system) and genotypic [multilocus sequence typing (MLST)] methods. Among the PJI isolates, the majority (67%) were multidrug-resistant. Two major clusters of PJI isolates could be identified; 44% belonged to MLST sequence type (ST) 2, all but one were of agr type 1, and 31% were assigned ST215 and were of agr type 3. Of the commensal isolates, only one isolate was multidrug-resistant, and they were more molecular epidemiologically diverse with mainly MLST singletons and a maximum of 3 isolates assigned to the identical ST. Biofilm production was detected in 41% of the PJI isolates and 58% of the commensal isolates, with the aap gene (95%) more frequently detected than the ica genes (62%) in the biofilm-positive isolates. In conclusion, S. epidermidis isolated from PJIs and commensal isolates differed regarding antimicrobial sensitivity and molecular epidemiological typing using MLST, but not substantially in the distribution of agr types, biofilm production, or the presence of ica and aap genes.
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| 14. |
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| 15. |
- Hellmark, Bengt, et al.
(författare)
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In vitro antimicrobial synergy testing of coagulase-negative staphylococci isolated from prosthetic joint infections using Etest and with a focus on rifampicin and linezolid
- 2010
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Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - Berlin : Springer. - 0934-9723 .- 1435-4373. ; 29:5, s. 591-595
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, coagulase-negative staphylococci (CoNS) have been increasingly recognised as causative agents of various infections, especially in immunocompromised patients and related to implanted foreign body materials. CoNS, and especially Staphylococcus epidermidis, transform into a stationary growth phase and produce biofilm when involved in a foreign body infection, making them difficult to eradicate with antimicrobials. Rifampicin has the ability to penetrate biofilm, but resistance may develop rapidly. To reduce the emergence of resistance, rifampicin should be combined with additional antimicrobials, of which several different ones have been proposed, including the relatively new class of antimicrobials, oxazolidinones, represented by linezolid. Thirty-seven CoNS isolates from patients with prosthetic joint infection were investigated by synergy testing using Etest. Nine antimicrobial combinations, based on either rifampicin or linezolid, were tested. For 16 (43%) of the isolates, a synergistic (n = 5), additive (n = 14) and/or antagonistic (n = 11) effect were identified. In conclusion, Etest is an objective and easily performed in vitro method for antimicrobial synergy testing. However, each isolate requires testing for the specific combination considered for treatment.
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| 16. |
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| 17. |
- Hellmark, Bengt, 1971-, et al.
(författare)
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Staphylococcal cassette chromosome mec (SCCmec) and arginine catabolic mobile element (ACME) in Staphylococcus epidermidis isolated from prosthetic joint infections
- 2013
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Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - New York, USA : Springer. - 0934-9723 .- 1435-4373. ; 32:5, s. 691-697
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the present study was to characterise the staphylococcal cassette chromosome mec (SCCmec) in Staphylococcus epidermidis isolated from prosthetic joint infections (PJIs) and, if possible, assign them to any of the presently known SCCmec types. In addition, the isolates were examined for the presence of the arginine catabolic mobile element (ACME). Sixty-one S. epidermidis isolates obtained from PJIs and 24 commensal S. epidermidis isolates were analysed. The mecA gene was detected in 49 of the 61 (80 %) PJI isolates and in four of the 24 (17 %) commensal isolates, and the composition of the SCCmec was further analysed. SCCmec types I and IV were the most common types among the PJI isolates. However, for over half (57 %) of the isolates, it was not possible to assign an SCCmec type. ACME was detected in eight (13 %) of the PJI isolates and in 14 (58 %) of the commensal isolates. The characterisation of the SCCmec elements revealed a large heterogeneity, with a high frequency of isolates carrying more than one type of the ccr gene complex. ACME was more common among the commensal isolates and may represent a survival benefit for S. epidermidis colonising healthy individuals in the community.
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| 18. |
- Hopkins, Francis, et al.
(författare)
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Pentameric C-reactive protein is a better prognostic biomarker and remains elevated for longer than monomeric CRP in hospitalized patients with COVID-19
- 2023
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Ingår i: Frontiers in Immunology. - : FRONTIERS MEDIA SA. - 1664-3224. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- The differing roles of the pentameric (p) and monomeric (m) C-reactive protein (CRP) isoforms in viral diseases are not fully understood, which was apparent during the COVID-19 pandemic regarding the clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Herein, we investigated the predictive value of the pCRP and mCRP isoforms for COVID-19 severity in hospitalized patients and evaluated how the levels of the protein isoforms changed over time during and after acute illness. This study utilized samples from a well-characterized cohort of Swedish patients with SARS-CoV-2 infection, the majority of whom had known risk factors for severe COVID-19 and required hospitalization. The levels of pCRP were significantly raised in patients with severe COVID-19 and in contrast to mCRP the levels were significantly associated with disease severity. Additionally, the pCRP levels remained elevated for at least six weeks post inclusion, which was longer compared to the two weeks for mCRP. Our data indicates a low level of inflammation lasting for at least six weeks following COVID-19, which might indicate that the disease has an adverse effect on the immune system even after the viral infection is resolved. It is also clear that the current standard method of testing pCRP levels upon hospitalization is a useful marker for predicting disease severity and mCRP testing would not add any clinical relevance for patients with COVID-19.
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| 19. |
- Hopkins, Francis R., et al.
(författare)
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Major alterations to monocyte and dendritic cell subsets lasting more than 6 months after hospitalization for COVID-19
- 2023
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Ingår i: Frontiers in Immunology. - : Frontiers Media S.A.. - 1664-3224. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: After more than two years the Coronavirus disease-19 (COVID-19) pandemic continues to burden healthcare systems and economies worldwide, and it is evident that the effects on the immune system can persist for months post-infection. The activity of myeloid cells such as monocytes and dendritic cells (DC) is essential for correct mobilization of the innate and adaptive responses to a pathogen. Impaired levels and responses of monocytes and DC to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is likely to be a driving force behind the immune dysregulation that characterizes severe COVID-19.Methods: Here, we followed a cohort of COVID-19 patients hospitalized during the early waves of the pandemic for 6-7 months. The levels and phenotypes of circulating monocyte and DC subsets were assessed to determine both the early and long-term effects of the SARS-CoV-2 infection.Results: We found increased monocyte levels that persisted for 6-7 months, mostly attributed to elevated levels of classical monocytes. Myeloid derived suppressor cells were also elevated over this period. While most DC subsets recovered from an initial decrease, we found elevated levels of cDC2/cDC3 at the 6-7 month timepoint. Analysis of functional markers on monocytes and DC revealed sustained reduction in program death ligand 1 (PD-L1) expression but increased CD86 expression across almost all cell types examined. Finally, C-reactive protein (CRP) correlated positively to the levels of intermediate monocytes and negatively to the recovery of DC subsets.Conclusion: By exploring the myeloid compartments, we show here that alterations in the immune landscape remain more than 6 months after severe COVID-19, which could be indicative of ongoing healing and/or persistence of viral antigens.
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| 20. |
- Hultberg, Jonas, et al.
(författare)
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In-depth immune profiling reveals advanced B- and T-cell differentiation to be associated with Th1-driven immune dysregulation in common variable immunodeficiency
- 2023
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Ingår i: Clinical Immunology. - : ACADEMIC PRESS INC ELSEVIER SCIENCE. - 1521-6616 .- 1521-7035. ; 257
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Tidskriftsartikel (refereegranskat)abstract
- Common variable immunodeficiency (CVID) is an inborn error of immunity characterized by low levels of an-tibodies. In addition to infections, many patients also suffer from T-helper 1-driven immune dysregulation, which is associated with increased mortality. The aim of this study was to perform in-depth characterization of the T and the B cell compartments in a well-defined cohort of patients affected by CVID and correlate the findings to the level of clinical immune dysregulation. We used mass cytometry, targeted proteomics, flow cytometry and functional assays to delineate the immunological phenotype of 15 CVID-affected patients with different levels of immune dysregulation. Unbiased clustering of T cell mass cytometry data correlated with CVID-related immune dysregulation and plasma protein profiles. Expanded CXCR3+ T-bet-expressing B cells correlated with effector memory CD4+ T cell clusters, and increased plasma levels of CXCR3-ligands. Our findings indicate an interplay between B cells and T cells in CVID-related immune dysregulation and provide a better understanding of the underlying pathological mechanisms.
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| 21. |
- Hultberg, Jonas, et al.
(författare)
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Plasma protein profiling reflects T(H)1-driven immune dysregulation in common variable immunodeficiency
- 2020
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Ingår i: Journal of Allergy and Clinical Immunology. - : MOSBY-ELSEVIER. - 0091-6749 .- 1097-6825. ; 146:2, s. 417-428
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Tidskriftsartikel (refereegranskat)abstract
- Background: Common variable immunodeficiency (CVID) is a disorder characterized by antibody deficiency. A significant fraction of the patients suffer from immune dysregulation, which leads to increased morbidity and mortality. The pathogenesis of this condition is poorly understood. Objective: Our aim was to find out whether the plasma protein signature in CVID is associated with clinical characteristics and lymphocyte aberrations. Methods: A highly sensitive proximity extension assay was used for targeted profiling of 145 plasma proteins in 29 patients with CVID. Phenotyping of peripheral lymphocytes was done by flow cytometry. The findings were correlated with the burden of immune dysregulation. Results: Unsupervised clustering of plasma protein profiles identified 2 distinct groups of patients with CVID that differed significantly in terms of the degree of complications due to immune dysregulation and in terms of the frequency of activated B- and T-cell subpopulations. Pathway analysis identified IFN-gamma and IL-1 beta as the top enriched upstream regulators associated with higher grade of immune dysregulation. In addition, CVID was found to be associated with increased plasma levels of the B-cell attracting chemokine CXCL13. Conclusion: Clustering based on plasma protein profiles delineated a subgroup of patients with CVID with activated T cells and clinical complications due to immune dysregulation. Thus, data indicate that CVID-associated immune dysregulation is a T(H)1-mediated inflammatory process driven by the IFN-gamma pathway.
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| 22. |
- Iversen, Søren, et al.
(författare)
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Alteration of Bacterial Communities in Anterior Nares and Skin Sites of Patients Undergoing Arthroplasty Surgery : Analysis by 16S rRNA and Staphylococcal-Specific tuf Gene Sequencing
- 2020
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Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 8:12
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to study alterations of bacterial communities in patients undergoing hip or knee arthroplasty to assess the impact of chlorhexidine gluconate soap decolonisation and systemic antibiotic prophylaxis. A Swedish multicentre, prospective collection of samples obtained from elective arthroplasty patients (n = 83) by swabbing anterior nares, skin sites in the groin and the site of planned surgery, before and after arthroplasty surgery, was analysed by 16S rRNA (V3-V4) gene sequencing and a complementary targeted tuf gene sequencing approach to comprehensively characterise alterations in staphylococcal communities. Significant reductions in alpha diversity was detected for both bacterial (p = 0.04) and staphylococcal (p = 0.03) groin communities after arthroplasty surgery with significant reductions in relative Corynebacterium (p = 0.001) abundance and Staphylococcus hominis (p = 0.01) relative staphylococcal abundance. In nares, significant reductions occurred for Staphylococcus hominis (p = 0.02), Staphylococcus haemolyticus (p = 0.02), and Staphylococcus pasteuri (p = 0.003) relative to other staphylococci. Staphylococcus aureus colonised 35% of anterior nares before and 26% after arthroplasty surgery. Staphylococcus epidermidis was the most abundant staphylococcal species at all sampling sites. No bacterial genus or staphylococcal species increased significantly after arthroplasty surgery. Application of a targeted tuf gene sequencing approach provided auxiliary staphylococcal community profiles and allowed species-level characterisation directly from low biomass clinical samples.
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| 23. |
- Khassebaf, Jasmine, et al.
(författare)
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Antibiotic susceptibility of Propionibacterium acnes isolated from orthopaedic implant-associated infections
- 2015
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 32, s. 57-62
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Prosthetic joint infections (PJIs) caused by Propionibacterium acnes account for a larger proportion of the total number of PJIs than previously assumed and thus knowledge of the antimicrobial susceptibility patterns of P. acnes is of great value in everyday clinical practice.Materials and methods: Using Etest, the present study investigated the susceptibility of 55 clinical isolates of P. acnes, obtained from orthopaedic implant-associated infections of the knee joint (n = 5), hip joint (n = 17), and shoulder joint (n = 33), to eight antimicrobial agents: benzylpenicillin, clindamycin, metronidazole, fusidic acid, doxycycline, moxifloxacin, linezolid and rifampicin. Synergy testing was also conducted, in which rifampicin was combined with each of the remaining seven antibiotics.Results: All isolates (n = 55) were susceptible to most of the antibiotics tested, with the exception of 100% resistance to metronidazole, five (9.1%) isolates displaying decreased susceptibility to clindamycin, and one (1.8%) to moxifloxacin. None of the antimicrobial agents investigated were synergistic with each other when combined and nine isolates were antagonistic for various antimicrobial combinations. The majority of the antimicrobial combinations had an indifferent effect on the isolates of P. acnes. However, the combination of rifampicin and benzylpenicillin showed an additive effect on nearly half of the isolates.Conclusion: Almost all P. acnes, isolated from orthopaedic implant-associated infections, predominantly PJIs, were susceptible to the antibiotics tested, with the exception of complete resistance to metronidazole. Synergy test could not demonstrate any synergistic effect but additive effects were found when combining various antibiotics. Antagonistic effects were rare.
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| 24. |
- Koskela, Anita, 1979-, et al.
(författare)
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Prevalence of the ica operon and insertion sequence IS256 among Staphylococcus epidermidis prosthetic joint infection isolates
- 2009
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Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - Berlin : Springer. - 0934-9723 .- 1435-4373. ; 28:6, s. 655-660
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Tidskriftsartikel (refereegranskat)abstract
- Joint replacement surgery has improved the quality of life for hundreds of thousands of patients. However, the infection of a joint implant is an important and serious complication, though the prevalence is low. Staphylococcus epidermidis is the most important pathogen involved in foreign-body infections. S. epidermidis is also a commensal that comprises a substantial part of the normal skin flora of humans. The possibility to demonstrate potential specific virulence markers may facilitate the interpretation of the bacteriological findings, as well as the clinical decision. The prevalence of the ica locus and insertion sequence IS256 by using polymerase chain reaction (PCR) among 32 clinical S. epidermidis isolates from prosthetic joint infections (PJIs) and 24 commensal isolates from nares and skin was investigated. Sixteen (50%) of the 32 PJI isolates harbored the ica operon compared with one-third of the commensal isolates obtained from the samples of the skin and nares of healthy individuals. The IS256 was demonstrated in 26 (81%) out of 32 PJI isolates. By contrast, IS256 was found in one of 24 commensal isolates. In conclusion, IS256 may be superior to the ica operon as a marker of the invasive capacity of S. epidermidis, since it was found in most of the PJI isolates, but rarely among commensals.
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| 25. |
- Liew-Littorin, C., et al.
(författare)
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Clonal diversity of Cutibacterium acnes (formerly Propionibacterium acnes) in prosthetic joint infections
- 2019
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Ingår i: Anaerobe. - : Elsevier. - 1075-9964 .- 1095-8274. ; 59, s. 54-60
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Tidskriftsartikel (refereegranskat)abstract
- Prosthetic joint infections (PJIs) are rare but feared complications following joint replacement surgery. Cutibacterium acnes is a skin commensal that is best known for its role in acne vulgaris but can also cause invasive infections such as PJIs. Some phylotypes might be associated with specific diseases, and recently, a plasmid was detected that might harbour important virulence genes. In this study, we characterized C. acnes isolates from 63 patients with PJIs (n=140 isolates) and from the skin of 56 healthy individuals (n=56 isolates), using molecular methods to determine the phylotype and investigate the presence of the plasmid. Single-locus sequence typing and a polymerase chain reaction designed to detect the plasmid were performed on all 196 isolates. No statistically significant differences in sequence types were seen between the two study groups indicating that the C. acnes that causes PJIs originates from the patients own normal skin microbiota. Of the 27 patients with multiple tissue samples, 19 displayed the same sequence types among all their samples. Single-locus sequence typing identified different genotypes among consecutive C. acnes isolates from four patients with recurrent infections. The plasmid was found among 17 isolates distributed in both groups, indicating that it might not be a marker for virulence regarding PJIs. Patients presenting multiple sequence types in tissue samples may represent contamination or a true polyclonal infection due to C. acnes.
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| 26. |
- Littorin, C., et al.
(författare)
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In vitro activity of tedizolid and linezolid against Staphylococcus epidermidis isolated from prosthetic joint infections
- 2017
-
Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - : Springer. - 0934-9723 .- 1435-4373. ; 36:9, s. 1549-1552
-
Tidskriftsartikel (refereegranskat)abstract
- Prosthetic joint infections (PJIs) are rare but long-lasting and are serious complications without any spontaneous resolution, requiring additional surgery and long-term treatment with antibiotics. Staphylococci are the most important aetiological agents of PJIs, and among the coagulase-negative staphylococci Staphylococcus epidermidis is the most common. However, S. epidermidis often displays multidrug resistance (MDR), demanding additional treatment options. The objective was to examine the effectiveness of tedizolid and linezolid against S. epidermidis isolated from PJIs. The standard antibiotic susceptibility pattern of S. epidermidis (n = 183) obtained from PJIs was determined by disc diffusion test, and MIC was determined by Etest for tedizolid, linezolid, and vancomycin. Tedizolid displayed MIC values ranging from 0.094 to 0.5 mg/L (MIC50: 0.19 mg/L, MIC90: 0.38 mg/L), linezolid MIC values ranging from 0.25 to 2 mg/L (MIC50: 0.75 mg/L, MIC90: 1 mg/L), and vancomycin MIC values ranging from 0.5 to 3 mg/L (MIC50 and MIC90 both 2 mg/L). According to the disc diffusion test, 153/183 (84%) isolates were resistant to ≥3 antibiotic groups, indicating MDR. In conclusion, S. epidermidis isolates from PJIs were fully susceptible, and the MIC50 and MIC90 values for tedizolid were two- to four-fold dilution steps lower compared with linezolid. Tedizolid is not approved, and there are no reports of long-term treatment, but it may display better tolerability and fewer adverse effects than linezolid; it thus could be a possible treatment option for PJIs, alone or in combination with rifampicin.
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| 27. |
- Månsson, Emeli, 1978-, et al.
(författare)
-
Comparative genomics of Staphylococcus epidermidis from prosthetic : from prosthetic-joint infections and nares highlights genetic traits associated with antimicrobial resistance, not virulence
- 2021
-
Ingår i: Microbial Genomics. - London, United Kingdom : Society for General Microbiology. - 2057-5858. ; 7:2
-
Tidskriftsartikel (refereegranskat)abstract
- There is increased awareness of the worldwide spread of specific epidemic multidrug-resistant (MDR) lineages of the human commensal Staphylococcus epidermidis. Here, using bioinformatic analyses accounting for population structure, we determined genomic traits (genes, SNPs and k-mers) that distinguish S. epidermidis causing prosthetic-joint infections (PJIs) from commensal isolates from nares, by analysing whole-genome sequencing data from S. epidermidis from PJIs prospectively collected over 10 years in Sweden, and contemporary S. epidermidis from the nares of patients scheduled for arthroplasty surgery. Previously suggested virulence determinants and the presence of genes and mutations linked to antimicrobial resistance (AMR) were also investigated. Publicly available S. epidermidis sequences were used for international extrapolation and validation of findings. Our data show that S. epidermidis causing PJIs differed from nasal isolates not by virulence but by traits associated with resistance to compounds used in prevention of PJIs: β-lactams, aminoglycosides and chlorhexidine. Almost a quarter of the PJI isolates did not belong to any of the previously described major nosocomial lineages, but the AMR-related traits were also over-represented in these isolates, as well as in international S. epidermidis isolates originating from PJIs. Genes previously associated with virulence in S. epidermidis were over-represented in individual lineages, but failed to reach statistical significance when adjusted for population structure. Our findings suggest that the current strategies for prevention of PJIs select for nosocomial MDR S. epidermidis lineages that have arisen from horizontal gene transfer of AMR-related traits into multiple genetic backgrounds.
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| 28. |
- Månsson, Emeli, 1978-, et al.
(författare)
-
Lower activation of caspase-1 by Staphylococcus epidermidis isolated from prosthetic joint infections compared to commensals
- 2018
-
Ingår i: Journal of bone and joint infection. - : IVYSPRING. - 2206-3552. ; 3:1, s. 10-14
-
Tidskriftsartikel (refereegranskat)abstract
- Nosocomial sequence types of Staphylococcus epidermidis dominate in prosthetic joint infections. We examined caspase-1 activation in human neutrophils after incubation with Staphylococcus epidermidis isolated from prosthetic joint infections and normal skin flora. Active caspase-1 was lower after incubation with isolates from prosthetic joint infections than after incubation with commensal isolates. Both host and isolate dependent differences in active caspase-1 were noted. Our results indicate that there might be a host-dependent incapacity to elicit a strong caspase-1 response towards certain strains of S. epidermidis. Further experiments with a larger number of individuals are warranted.
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| 29. |
- Månsson, Emeli, 1978-, et al.
(författare)
-
Methicillin-Resistant Staphylococcus epidermidis Lineages in the Nasal and Skin Microbiota of Patients Planned for Arthroplasty Surgery
- 2021
-
Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 9:2
-
Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus epidermidis, ubiquitous in the human nasal and skin microbiota, is a common causative microorganism in prosthetic joint infections (PJIs). A high proportion of PJI isolates have been shown to harbor genetic traits associated with resistance to/tolerance of agents used for antimicrobial prophylaxis in joint arthroplasties. These traits were found within multidrug-resistant S. epidermidis (MDRSE) lineages of multiple genetic backgrounds. In this study, the aim was to study whether MDRSE lineages previously associated with PJIs are present in the nasal and skin microbiota of patients planned for arthroplasty surgery but before hospitalization. We cultured samples from nares, inguinal creases, and skin over the hip or knee (dependent on the planned procedure) taken two weeks (median) prior to admittance to the hospital for total joint arthroplasty from 66 patients on agar plates selecting for methicillin resistance. S. epidermidis colonies were identified and tested for the presence of mecA. Methicillin-resistant S. epidermidis (MRSE) were characterized by Illumina-based whole-genome sequencing. Using this method, we found that 30/66 (45%) of patients were colonized with MRSE at 1-3 body sites. A subset of patients, 10/66 (15%), were colonized with MDRSE lineages associated with PJIs. The qacA gene was identified in MRSE isolates from 19/30 (63%) of MRSE colonized patients, whereas genes associated with aminoglycoside resistance were less common, found in 11/30 (37%). We found that MDRSE lineages previously associated with PJIs were present in a subset of patients' pre-admission microbiota, plausibly in low relative abundance, and may be selected for by the current prophylaxis regimen comprising whole-body cleansing with chlorhexidine-gluconate containing soap. To further lower the rate of S. epidermidis PJIs, the current prophylaxis may need to be modified, but it is important for possible perioperative MDRSE transmission events and specific risk factors for MDRSE PJIs to be investigated before reevaluating antimicrobial prophylaxis.
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| 30. |
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| 31. |
- Månsson, Emeli, 1978-
(författare)
-
Molecular epidemiology of Staphylococcus epidermidis in prosthetic joint infections
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Staphylococcus epidermidis is ubiquitous in the human microbiota, but also an important pathogen in healthcare-associated infections, such as prosthetic joint infections (PJIs). In this thesis, aspects of the molecular epidemiology of S. epidermidis in PJIs were investigated with the aim of improving our understanding of the pre- and perioperative measures required to reduce the incidence of S. epidermidis PJIs.In Paper I, S. epidermidis retrieved from air sampling in the operating field during arthroplasty was characterized by multilocus sequence typing and antibiotic susceptibility testing. No isolates belonging to sequence types (STs) 2 and 215, previously associated with PJIs, were found in the air of the operating field. During air sampling, several Staphylococcus pettenkoferi isolates were identified, and as a spin-off of Paper I, the genomic relatedness of these isolates to S. pettenkoferi isolates from blood cultures was described in Paper II.In Paper III, genetic traits distinguishing S. epidermidis isolated from PJIs were determined using genome-wide association study accounting for population effects after whole-genome sequencing (WGS) of a population- based 10-year collection of S. epidermidis isolates from PJIs and of nasal isolates retrieved from patients scheduled for arthroplasty. Genes associated with antimicrobial agents used for prophylaxis in arthroplasty, i.e., beta-lactam antibiotics, aminoglycosides, and chlorhexidine, were associated with PJI origin. S. epidermidis from PJIs were dominated by the ST2a, ST2b, ST5, and ST215 lineages.In Paper IV, selective agar plates were used to investigate colonization with methicillin resistant S. epidermidis (MRSE) in patients scheduled for arthroplasty. MRSE were further characterized by WGS. A subset of patients was found to harbour PJI-associated S. epidermidis lineages in their microbiota before hospitalization, but no isolates belonging to the ST2a lineage nor any rifampicin-resistant isolates were retrieved.
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| 32. |
- Månsson, Emeli, 1978-, et al.
(författare)
-
Staphylococcus epidermidis from prosthetic joint infections induces lower IL-1 release from human neutrophils than isolates from normal flora
- 2018
-
Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley-Blackwell Publishing Inc.. - 0903-4641 .- 1600-0463. ; 126:8, s. 678-684
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to test the hypothesis that Staphylococcus epidermidis isolated from prosthetic joint infections (PJIs) differs from S.epidermidis isolated from normal flora in terms of its capacity to induce activation of caspase-1 and release of IL-1 in human neutrophils. The amount of active caspase-1 was determined over 6h by detecting Ac-YVAD-AMC fluorescence in human neutrophils incubated with S.epidermidis isolates from PJIs (ST2) or normal flora. The amount of IL-1 was detected by ELISA in neutrophil supernatants after 6h of incubation. Mean IL-1 release was lower after incubation with S.epidermidis from PJIs compared to isolates from normal flora, but no statistically significant difference was found in active caspase-1. Substantial inter-individual differences in both active caspase-1 and IL-1 were noted. These results suggest that evasion of innate immune response, measured as reduced capacity to induce release of IL-1 from human neutrophils, might be involved in the predominance of ST2 in S.epidermidis PJIs, but that other microbe-related factors are probably also important.
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| 33. |
- Nilsdotter-Augustinsson, Åsa, 1962-, et al.
(författare)
-
Adherence of Staphylococcus epidermidis to extracellular matrix proteins and effects of fibrinogen-bound bacteria on oxidase activity and apoptosis in neutrophils
- 2005
-
Ingår i: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS). - : Wiley. - 0903-4641 .- 1600-0463. ; 113:5, s. 361-373
-
Tidskriftsartikel (refereegranskat)abstract
- Staphylococcus epidermidis often causes foreign-body infections such as those associated with hip prostheses, but the underlying pathogenic mechanisms are not fully understood. We performed spectrophotometry to study the ability of S. epidermidis to bind to immobilised fibrinogen, fibronectin, vitronectin, and collagen. The strains were isolated from infected hip prostheses or from normal flora and the well-known protein-binding strain Staphylococcus aureus Cowan was used as positive control. We also analysed the interaction between neutrophils and a fibrinogen-bound prosthesis-derived strain of S. epidermidisby measuring chemiluminescence to determine the neutrophil oxidative response and binding of annexin V to indicate neutrophil apoptosis. We found that binding of S. epidermidis to extracellular matrix proteins varied under different growth conditions, and that prosthesis isolates adhered better to vitronectin than did strains from normal flora. The oxidative response caused by fibrinogen-bound S. epidermidis was not above the background level, which was in marked contrast to the distinct response induced by fibrinogen-associated S. aureus Cowan. Furthermore, fibrinogen-adhering S. epidermidis retarded neutrophil apoptosis. We conclude that surface-bound S. epidermidis induces only a weak inflammatory response, which in combination with the ability of the adherent bacteria to retard neutrophil apoptosis may contribute to low-grade inflammation and loosening of prostheses.
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| 34. |
- Nilsdotter-Augustinsson, Åsa, et al.
(författare)
-
Characterization of coagulase-negative staphylococci isolated from patients with infected hip prostheses : use of phenotypic and genotypic analyses, including tests for the presence of the ica operon
- 2007
-
Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - Berlin : Springer. - 0934-9723 .- 1435-4373. ; 26:4, s. 255-65
-
Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to investigate phenotypic and/or genotypic heterogeneity in coagulase-negative staphylococci (CoNS) obtained from multiple tissue samples taken perioperatively during exchange surgery from each of 19 patients with clinically and/or microbiologically proven hip prosthesis infections. CoNS are important pathogens in prosthetic hip joint infections. Several virulence factors have been suggested for CoNS, such as phenotypic variation, yet the pathogenic processes that are involved remain unclear. The PhenePlate system (PhPlate AB, Stockholm Sweden) was used for phenotyping and pulsed-field gel electrophoresis for genotyping of polymorphisms in isolates of CoNS. Furthermore, polymerase chain reaction was used to determine the presence of the icaADB gene complex in the isolates. Some patients were infected with CoNS and other species, some were infected with multiple CoNS species, although infections with Staphylococcus epidermidis alone were most common, and some were infected with different S. epidermidis clones. Phenotypic variation was found among isolates both from the same tissue sample and from different samples from the same patient, and in some cases such variation represented the presence of different clones. One-third of the patients infected with S. epidermidis carried the icaADB genes. CoNS isolates showing phenotypic and/or genotypic heterogeneity were identified in tissue samples from half of the patients. The presence of the intercellular adhesion (ica) operon does not seem to be a prerequisite for establishing infection with CoNS.
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| 35. |
- Nilsdotter-Augustinsson, Åsa
(författare)
-
Coagulase-negative staphylococci in prosthetic hip infections
- 2005
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- More than 11,000 primary total hip replacements were performed in Sweden in the year 2000, corresponding to 125 primary total hip replacements per 100,000 inhabitants, according to The Swedish Total Hip Replacement Register. In general, this procedure provides highly satisfactory results. The most common complications associated with prosthetic hip joints are aseptic biomechanical failures and infections. Delayed low-grade infections occur most often, and they are also the most difficult to distinguish from aseptic mechanical failures because of similar symptoms.During the period 1994 to 2001, a prospective study was conducted to compare inflammatory markers in blood, synovial fluid, and histopathological specimens in patients diagnosed with aseptic or septic loosening of hip prostheses. Coagulase-negative staphylococci (CoNS) were found to be the most common pathogens in the patients with prosthetic hip joint infections.Further characterisation of the CoNS revealed that patients were co-infected with the following: (i) CoNS and other bacterial species, (ii) various CoNS species, and (iii) different S. epidermidis clones. Expression of the icaADB gene complex, which is important for the biofilm mode-of-growth characteristic of S. epidermidis, was not necessary to allow S. epidermidis to infect orthopaedic prostheses. The majority of the S. epidermidis isolates, both from prostheses and normal bacteria flora, were able to bind to at least one of the extracellular matrix proteins we tested, this adhesion ability is a probable virulence factor. Histologically, the extent of cell infiltration differed between aseptic and septic loosening of prostheses, and neutrophils in tissue at a rate of ≥ 5 cells/high power field greatly favoured infection. Periprosthetic tissue contained the cells that are required not only for an innate, but also a specific, immune response, which supports the theory that the limited systemic inflammatory response in infections of hip prostheses is not due to failure of inflammatory cells to reach the infected area, but is more likely caused by an inadequate response to the infecting organisms.Therefore, we studied the interactions between neutrophils and S. epidermidis (the most common CoNS species in hip prosthetic infections). Neutrophils phagocytosed both surfaceadherent and planktonic S. epidermidis, but they ingested adherent S. aureus isolates more readily than they consumed adherent S. epidermidis. The reduced phagocytosis of S. epidermidis by neutrophils is viewed as a virulence factor, together with the lack of an ability to prime or sufficiently activate the neutrophil oxidase, and thereby evade adequate killing by neutrophils. The weak oxidative activation agrees with the low inflammatory response seen in patients with S. epidermidis infections related to implanted devices. Furthermore, both planktonic and adherent S. epidermidis delayed neutrophil apoptosis, and we suggest that this leads to the accumulation of neutrophils at the site of inflammation. We propose that the complex interplay between the S. epidermidis-induced delay in apoptosis in neutrophils and the interaction of S. epidermidis-containing neutrophils with macrophages in periprosthetic tissue has negative impact on the outcome in patients with prosthetic hip joint infections, resulting in low grade inflammation, tissue damage, and finally loosening of the prosthesis.
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| 36. |
- Nilsdotter-Augustinsson, Åsa, 1962-
(författare)
-
Gastroenterit
- 2022. - 2
-
Ingår i: Infektionsmedicin. - Lund : Studentlitteratur AB. - 9789144153308 ; , s. 55-68
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 37. |
- Nilsdotter-Augustinsson, Åsa, 1962-
(författare)
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Handläggning av infektioner vid ortopediska implantat en utmaning för vården
- 2019
-
Ingår i: Läkartidningen. - Stockholm. - 0023-7205 .- 1652-7518. ; 116:FR6C, s. 1-6
-
Tidskriftsartikel (refereegranskat)abstract
- The Swedish National Guidelines for Bone and Joint Infections were revised during 2018. The work was carried out on behalf of the Swedish Society for Infectious Diseases. The study group consists of senior consultants in infectious diseases, supported by specialists in orthopedic surgery, clinical microbiology and allergology when needed. The study group emphasizes that implant associated infections are challenging and requires multidisciplinary cooperation, including, but not limited to, specialists in orthopedic surgery, infectious diseases, clinical microbiology and radiology for optimal treatment results. All aspects of the clinical management are equally important; selecting the optimal antibiotic prophylaxis in arthroplasty as well as fracture surgery, early diagnosis of infection, adequate treatment, follow-up, and finally a structured evaluation of outcome. Profound and updated knowledge of treatment of biofilm related infection is necessary to achieve optimal results in patients with implant-associated infections. Future challenges include improved decision support for combining surgical treatment with selection of proper antibiotics, as well as management of antibiotic resistance, drug-drug interactions and adverse effects of antibiotic treatment.
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| 38. |
- Nilsdotter-Augustinsson, Åsa, et al.
(författare)
-
Inflammatory response in 85 patients with loosened hip prostheses : A prospective study comparing inflammatory markers in patients with aseptic and septic prosthetic loosening
- 2007
-
Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3674 .- 1745-3682. ; 78:5, s. 629-639
-
Tidskriftsartikel (refereegranskat)abstract
- Over the past decades, prosthetic hip joints have improved the quality oflife for many patients. The most common complications are aseptic biornechanical failures and prosthetic joint infections. For prosthetic hip joints, delayed low-grade infections are seen most often and they are also most difficult to distinguish from aseptic mechanical failures. A prospective study was conducted to campare inilammatory markers in patients diagnosed with aseptic or septic prosthetic loosenffig. The diagnostic criteria were based on the decisions of experienced orthoperlic surgeons and microbiological analys is of periprosthetic tissue samplestaken perioperatively. Coagulase-negative staphylococci were the most common pathogens in the infected patients. Pre- or perioperative results for C-reactive protein and erytlu-ocyte sedimentation rate were valuable tools for diagnosing most, hut not all, low virulence infections. White blood cell count in synavial fluid was an important marker of infection, which was not the case for lactate. Levels of the cytokines turnor necrosis factor-α, interleukin-1 ß. and interleukin-6 in synavial fluid were significantly higher in the infected group. Patterus of inilammatory cell infiltration in periprosthetic tissue differed significantly between the groups, and infiltration of polymorphonuclear cells proved to be the best marker of distinguish between septic and aseptic loosenffig. Treatment and outcome are described for the infected patients.
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| 39. |
- Nyström, Katarina, et al.
(författare)
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Specific T-cell responses for guiding treatment with convalescent plasma in severe COVID-19 and humoral immunodeficiency : a case report
- 2022
-
Ingår i: BMC Infectious Diseases. - : BMC. - 1471-2334. ; 22:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background The immune response to SARS-CoV-2 virus, the cause of COVID-19, is complex. Antibody mediated responses are important for viral clearance but may also drive hyperinflammation in severe COVID-19. We present a case of an individual with a genetic inability to produce antibodies and severe COVID-19, receiving no other specific anti-viral treatment than convalescent COVID-19 plasma, illustrating that hyperinflammation can occur in the absence of a humoral anti-viral response. In addition, the case illustrates that the assessment of SARS-CoV-2 T cell responses can facilitate clinical decision making in patients with COVID-19 and weak or absent humoral immune responses. Case presentation A male with X-linked agammaglobulinemia on regular immunoglobulin replacement therapy, hospitalized for 35 days due to severe COVID-19. Systemic inflammatory parameters were highly elevated. After treatment with convalescent COVID-19 plasma he became afebrile and the fatigue diminished. He was discharged on day 42 and nasopharyngeal SARS-CoV-2 PCR eventually was negative on day 49. Evidence of SARS-CoV-2 specific T cells prior to administration of plasma therapy suggested that antibodies were crucial for viral clearance. Regular assessment showed robust and persistent SARS-CoV-2 specific T-cell responses after recovery suggested that prophylactic administration of convalescent COVID-19 plasma was unnecessary. Conclusion Assessment of SARS-CoV-2T-cell responses can facilitate the clinical management of COVID-19 patients with humoral immunodeficiencies.
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| 40. |
- Nyström, Sofia, et al.
(författare)
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Plasma Levels of mir-34a-5p Correlate with Systemic Inflammation and Low Naïve CD4 T Cells in Common Variable Immunodeficiency
- 2024
-
Ingår i: Journal of Clinical Immunology. - : SPRINGER/PLENUM PUBLISHERS. - 0271-9142 .- 1573-2592. ; 44:1
-
Tidskriftsartikel (refereegranskat)abstract
- PurposeCommon variable immunodeficiency (CVID) is a primary antibody deficiency that commonly manifests as recurrent infections. Many CVID patients also suffer from immune dysregulation, an inflammatory condition characterized by polyclonal lymphocytic tissue infiltration and associated with increased morbidity and mortality. The genetic cause is unknown in most CVID patients and epigenetic alterations may contribute to the broad range of clinical manifestations. MicroRNAs are small non-coding RNAs that are involved in epigenetic modulation and may contribute to the clinical phenotype in CVID.MethodsHere, we determined the circulating microRNAome and plasma inflammatory proteins of a cohort of CVID patients with various levels of immune dysregulation and compared them to healthy controls. A set of deregulated microRNAs was validated by qPCR and correlated to inflammatory proteins and clinical findings.ResultsLevels of microRNA-34a correlated with 11 proteins such as CXCL9, TNF, and IL10, which were predicted to be biologically connected. Moreover, there was a negative correlation between mir-34 levels and the number of naive CD4 T cells in CVID.ConclusionCollectively, our data show that microRNAs correlate with the inflammatory response in CVID. Further investigations are needed to elucidate the role of miRNAs in the development of CVID-related immune dysregulation.
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| 41. |
- Ottosson, Loa, et al.
(författare)
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Long Term Norovirus Infection in a Patient with Severe Common Variable Immunodeficiency
- 2022
-
Ingår i: Viruses. - : MDPI. - 1999-4915. ; 14:8
-
Tidskriftsartikel (refereegranskat)abstract
- Norovirus is the most common cause of acute non-bacterial gastroenteritis. Immunocompromised patients can become chronically infected, with or without symptoms. In Europe, common variable immunodeficiency (CVID) is one of the most common inborn errors of immunity. A potentially severe complication is CVID-associated enteropathy, a disorder with similar histopathology to celiac disease. Studies suggest that chronic norovirus infection may be a contributor to CVID enteropathy, and that the antiviral drug ribavirin can be effective against norovirus. Here, a patient with CVID-like disease with combined B- and T-cell deficiency, had chronic norovirus infection and enteropathy. The patient was routinely administered subcutaneous and intravenous immunoglobulin replacement therapy (SCIg and IVIg). The patient was also administered ribavirin for -7.5 months to clear the infection. Stool samples (collected 2013-2016) and archived paraffin embedded duodenal biopsies were screened for norovirus by qPCR, confirming a chronic infection. Norovirus genotyping was done in 25 stool samples. For evolutionary analysis, the capsid (VP1) and polymerase (RdRp) genes were sequenced in 10 and 12 stool samples, respectively, collected before, during, and after ribavirin treatment. Secretor phenotyping was done in saliva, and serum was analyzed for histoblood group antigen (HBGA) blocking titers. The chronic norovirus strain formed a unique variant subcluster, with GII.4 Den Haag [P4] variant, circulating around 2009, as the most recent common ancestor. This corresponded to the documented debut of symptoms. The patient was a secretor and had HBGA blocking titers associated with protection in immunocompetent individuals. Several unique amino acid substitutions were detected in immunodominant epitopes of VP1. However, HBGA binding sites were conserved. Ribavirin failed in treating the infection and no clear association between ribavirin-levels and quantity of norovirus shedding was observed. In conclusion, long term infection with norovirus in a patient with severe CVID led to the evolution of a unique norovirus strain with amino acid substitutions in immunodominant epitopes, but conservation within HBGA binding pockets. Regularly administered SCIg, IVIg, and similar to 7.5-month ribavirin treatment failed to clear the infection.
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| 42. |
- Petersson, Christina, 1975-, et al.
(författare)
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"Experiences of the burden of treatment" - patient-reports of facilitated subcutaneous immunoglobulin treatment in adults with immunodeficiency.
- 2018
-
Ingår i: Journal of Clinical Nursing. - : John Wiley & Sons. - 0962-1067 .- 1365-2702. ; 27:23-24, s. 4270-4278
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS AND OBJECTIVES: To evaluate patient-reported experiences of facilitated subcutaneous immunoglobulin treatment in adults with primary or secondary immunodeficiency.BACKGROUND: Decreased levels of circulating antibodies (humoral immunodeficiency) are often associated with higher infection rates which cause problems in daily living, for example symptoms of severe and recurrent bacterial infections that may cause chronic lung diseases. For some diagnoses, treatment with immunoglobulin becomes critical and life-long. The acceptability of administration forms is important to achieve adherence to treatment, and to increase quality of life for these patients.DESIGN: Convergent mixed method approach.METHODS: A structured telephone interview with nine questions evaluated on a score scale about treatment experience, satisfaction, and ancillary supplies was used, followed by open-ended questions for each item.RESULTS: Prohibiting factors were revealed, exemplified by problems due to technical issues and ancillary supply issues. Promoting factors was shown by high a satisfaction when combining treatment with daily life as well as increased wellbeing. Facilitated subcutaneous immunoglobulin treatment led to fewer treatment sessions, with a time-saving aspect also described by high scores in the item concerning longer treatment interval.CONCLUSIONS: The opportunity to be given the best possible treatment plan adjusted for each patients' situation is central. Healthcare professionals should discuss the different aspects that can promote and inhibit the outcomes of treatment.RELEVANCE TO CLINICAL PRACTICE: The results can help professionals to understand different factors that may impinge on the patients' everyday life when they are forced into a lifelong treatment regimen. This knowledge is also important for nurses who have a responsibility to promote health concerning patients with long-term conditions in general. This article is protected by copyright. All rights reserved.
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| 43. |
- Ridberg, Sara, et al.
(författare)
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Cutibacterium acnes (formerly Propionibacterium acnes) isolated from prosthetic joint infections is less susceptible to oxacillin than to benzylpenicillin
- 2019
-
Ingår i: Journal of bone and joint infection. - Sydney, NSW, Australia : Ivyspring International Publisher. - 2206-3552. ; 4:3, s. 106-110
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: The frequency of prosthetic joint infections (PJIs) due to Cutibacterium acnes (formerly Propionibacterium acnes) is increasing, especially shoulder PJIs. The recommended antibiotic prophylaxis for hip and knee arthroplasties is beta-lactam antibiotics, predominantly cephalosporins. However, for example in Sweden, isoxazolyl-penicillin cloxacillin is used. No specific recommendations for shoulder arthroplasties are available. The aim of the present study was to determine the minimum inhibitory concentration (MIC) values for different antibiotics for C. acnes; and, more specifically, to compare the MIC values for benzylpenicillin and oxacillin.Materials and methods: Minimum inhibitory concentration (MIC) values for nine different antibiotic agents were obtained by gradient test (Etest) using strains of C. acnes (n= 57) isolated from PJIs from shoulders (n=31), hips (n=21), and knees (n=5).Results: All isolates had low MIC values for most of the tested antibiotic agents, and showed a wild type MIC distribution. The exception was clindamycin with 9% of the isolates displaying decreased susceptibility. The MIC values obtained for benzylpenicillin were significantly lower than the MIC values for isoxazolyl-penicillin (oxacillin).Conclusion: These in vitro results indicate that benzylpenicillin might be a more effective prophylactic treatment to prevent shoulder PJIs caused by C. acnes. However, further studies on the subject are needed, and the effectiveness of the prophylactic treatment should be evaluated using randomized controlled studies and/or register-based studies.
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| 44. |
- Salih, Lavin, et al.
(författare)
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Staphylococcus epidermidis isolates from nares and prosthetic joint infections are mupirocin susceptible
- 2018
-
Ingår i: Journal of bone and joint infection. - : Ivyspring International Publisher. - 2206-3552. ; 3:1, s. 1-4
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Tidskriftsartikel (refereegranskat)abstract
- The objective of the present study was to investigate the antibiotic susceptibility including mupirocin among Staphylococcus. epidermidis isolated from prosthetic joint infections (PJIs) (n=183) and nasal isolates (n=75) from patients intended to undergo prosthetic joint replacements. Susceptibility to mupirocin (used for eradication of nasal carriership of Staphylococcus aureus) was investigated by gradient test, and susceptibility to various other antimicrobial agents was investigated by disc diffusion test. All isolates, except three from PJIs and one from the nares, were fully susceptible to mupirocin. Multi-drug resistance (≥3 antibiotic classes) was found in 154/183 (84.2%) of the PJI isolates but only in 2/75 (2.7%) of the nares isolates, indicating that S. epidermidis causing PJIs do not originate from the nares.
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| 45. |
- Sjöwall, Johanna, et al.
(författare)
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SARS-CoV-2 Specific Antibody Response and T Cell-Immunity in Immunocompromised Patients up to Six Months Post COVID : A Pilot Study
- 2022
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Ingår i: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 11:12
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Tidskriftsartikel (refereegranskat)abstract
- COVID-19 generates SARS-CoV-2-specific antibodies in immunocompetent individuals. However, in immunocompromised patients, the humoral immunity following infection may be impaired or absent. Recently, the assessment of cellular immunity to SARS-CoV-2, both following natural infection and vaccination, has contributed new knowledge regarding patients with low or no antibody responses. As part of a prospective cohort study which included hospitalized patients with COVID-19, we identified immunocompromised patients and compared them with age- and sex-matched immunocompetent patients regarding co-morbidities, biomarkers of COVID-19 and baseline viral load by real-time PCR in nasopharyngeal swabs. Spike and nucleocapsid antibody responses were analyzed at inclusion and after two weeks, six weeks and six months. Plasma immunoglobulin G (IgG) levels were quantified, lymphocyte phenotyping was performed, and SARS-CoV-2 specific CD4 and CD8 T cell responses after in vitro antigen stimulation were assessed at six months post infection. All patients showed IgG levels above or within reference limits. At six months, all patients had detectable SARS-CoV-2 anti-spike antibody levels. SARS-CoV-2 specific T cell responses were detected in 12 of 12 immunocompetent patients and in four of six immunocompromised patients. The magnitude of long-lived SARS-CoV-2 specific T cell responses were significantly correlated with the number of CD4 T cells and NK cells. Determining the durability of the humoral and cellular immune response against SARS-CoV-2 in immunocompromised individuals could be of importance by providing insights into the risk of re-infection and the need for vaccine boosters.
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| 46. |
- Sune, Dan, et al.
(författare)
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Optimization of 16S rRNA gene analysis for use in the diagnostic clinical microbiology service
- 2020
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Ingår i: Journal of Microbiological Methods. - : ELSEVIER. - 0167-7012 .- 1872-8359. ; 170
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Tidskriftsartikel (refereegranskat)abstract
- Broad-range amplification and sequencing of the 16S rRNA gene, directly from clinical samples, is a method that potentially allows detection of any cultivable or non-cultivable bacteria. However, the method is prone to false positive results due to PCR contamination. Another concern is the human DNA abundance compared to bacterial DNA in samples from sterile sites. Those factors may decrease the sensitivity and specificity of the assay and can complicate the analysis and interpretation of the results. The objective of this prospective study was to try to avoid the most common pitfalls, mentioned above, and develop a molecular 16S assay with a high clinical sensitivity and specificity. Fifty-six consecutive tissue samples from patients with suspected deep infections were extracted by 3 different DNA-extraction methods; two based on a principle of bacterial DNA enrichment, and one conventional DNA extraction method. We compared three primer pairs, including both conventional and DPO principle, targeting different variable regions of the 16S rRNA gene. Results from routine tissue culture were used as reference. Clinical data was recorded from patient charts and analyzed in parallel. Of a total of 56 samples, collected from 39 patients, 70% (39 samples) were assessed as true infections by analysis of clinical data. Bacterial enrichment extraction increased sensitivity from 54% to 72%. The 2 sets of primer pairs defining region V1-V3 and V3-V4, showed similar sensitivity, but DPO-primers resulted in better specificity, i.e. less contaminations. The primer pairs covering V1-V8 show significantly lower sensitivity (p amp;lt; .001) than V1-V3 and V3-V4. Optimizing extraction protocols and choice of primers can increase the sensitivity and specificity of a molecular 16S-analysis, rendering a valuable complement to tissue culture.
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| 47. |
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| 48. |
- Tevell, Staffan, 1975-, et al.
(författare)
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Handläggning av infektioner vid ortopediska implantat en utmaning för vården : [Treatment of orthopedic implant-associated infections]
- 2019
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Ingår i: Läkartidningen. - : Läkartidningen Förlag AB. - 0023-7205 .- 1652-7518. ; 116:43
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Forskningsöversikt (refereegranskat)abstract
- The Swedish National Guidelines for Bone and Joint Infections were revised during 2018. The work was carried out on behalf of the Swedish Society for Infectious Diseases. The study group consists of senior consultants in infectious diseases, supported by specialists in orthopedic surgery, clinical microbiology and allergology when needed. The study group emphasizes that implant associated infections are challenging and requires multidisciplinary cooperation, including, but not limited to, specialists in orthopedic surgery, infectious diseases, clinical microbiology and radiology for optimal treatment results. All aspects of the clinical management are equally important; selecting the optimal antibiotic prophylaxis in arthroplasty as well as fracture surgery, early diagnosis of infection, adequate treatment, follow-up, and finally a structured evaluation of outcome. Profound and updated knowledge of treatment of biofilm related infection is necessary to achieve optimal results in patients with implant-associated infections. Future challenges include improved decision support for combining surgical treatment with selection of proper antibiotics, as well as management of antibiotic resistance, drug-drug interactions and adverse effects of antibiotic treatment.
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| 49. |
- Tevell, Staffan, 1975-, et al.
(författare)
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Heterogeneous glycopeptide intermediate Staphylococcus epidermidis isolated from prosthetic joint infections
- 2014
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Ingår i: European Journal of Clinical Microbiology and Infectious Diseases. - New York : Springer. - 0934-9723 .- 1435-4373. ; 33:6, s. 911-917
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Tidskriftsartikel (refereegranskat)abstract
- Methicillin-resistant Staphylococcus epidermidis (MRSE) poses a major problem in prosthetic joint infections (PJIs). Vancomycin is often considered the drug of choice in the empirical treatment of staphylococcal PJIs. As recent decades have seen reports of heterogeneous glycopeptide intermediate S. aureus (hGISA), our aim was to examine the prevalence of heterogeneous glycopeptide intermediate S. epidermidis (hGISE) in PJIs. S. epidermidis isolates (n = 122) from 119 patients in three Swedish counties between 1993 and 2012 were included. All were isolated from perioperative tissue samples from revision surgery in clinically verified PJIs. Antimicrobial susceptibility testing against staphylococcal antibiotics was performed. The macromethod Etest (MME) and glycopeptide resistance detection (GRD) Etest were used to detect hGISE. Standard minimal inhibitory concentration (MIC) determination revealed no vancomycin-resistant isolates, while teicoplanin resistance was detected in 14 out of 122 isolates (11.5 %). hGISE was found in 95 out of 122 isolates (77.9 %), 64 out of 67 of isolates with teicoplanin MIC > 2 mg/L (95.5 %) and 31 out of 55 of isolates with teicoplanin MIC a parts per thousand currency sign2 mg/L (56.4 %). Thus, the presence of hGISE cannot be ruled out by teicoplanin MIC a parts per thousand currency sign2 mg/L alone. Multidrug resistance was detected in 86 out of 95 hGISE isolates (90.5 %) and in 16 out of 27 isolates (59.3 %), where hGISE could not be detected. In conclusion, hGISE detected by MME or GRD was common in this material. However, hGISE is difficult to detect with standard laboratory diagnostic routines. Glycopeptide treatment may not be sufficient in many of these PJIs, even if standard MIC classifies the isolated S. epidermidis as susceptible.
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| 50. |
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