| 1. |
- Antusheva, E., et al.
(författare)
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Outbreak of tuberculosis in a closed setting: views on transmission based on results from molecular and conventional methods
- 2016
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Ingår i: Journal of Hospital Infection. - : Elsevier BV. - 0195-6701. ; 93:2, s. 187-190
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Tidskriftsartikel (refereegranskat)abstract
- Background: This study describes an outbreak of tuberculosis (TB) in a nursing home for men with mental disorders where residency is lengthy or permanent. This type of setting can provide a model of transmission as contact with the rest of society is extremely limited. Aim: To determine if cases of TB, diagnosed around the same time and in the same place, are linked based on results using molecular and conventional methods. Methods: The strains of Mycobacterium tuberculosis were analysed by drug resistance testing and mycobacterial interspersed repetitive units-variable number tandem repeats (MIRU-VNTRV). Microbiological results were related to clinical history and time of diagnosis. Findings: Nine patients were diagnosed with TB, and strains were recovered from seven of these patients. Unexpectedly, the strains with the same genotype showed different patterns of resistance, and only two strains demonstrated identical patterns. MIRU-VNTR analysis demonstrated that one patient was infected with two different strains. Conclusion: Variation between the strains indicates that the outbreak may have arisen from several sources of infection. The variation in resistance indicates that rapid emergence of antimicrobial resistance is possible. As such, several questions are raised concerning source of infection, development of disease, resistance and mixed infections. (C) 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
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| 2. |
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| 3. |
- Brudey, Karine, et al.
(författare)
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Molecular epidemiology of Mycobacterium tuberculosis in western Sweden.
- 2004
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Ingår i: Journal of clinical microbiology. - 0095-1137. ; 42:7, s. 3046-51
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Tidskriftsartikel (refereegranskat)abstract
- The genetic diversity of Mycobacterium tuberculosis isolates among patients from Sweden was determined by a combination of two PCR-based techniques (spoligotyping and variable number of tandem repeats analysis). It resulted in a clustering of 23.6% of the isolates and a rate of recent transmission of 14.1%. The clustered isolates mainly belonged to the Haarlem family (23.2%), followed by the Beijing (9.8%), Latin American and Mediterranean (LAM; 8%), and East African-Indian (EAI; 6.2%) families. A comparison of the spoligotypes with those in the international spoligotyping database showed that 62.5% of the clustered isolates and 36.6% of all isolates typed were grouped into six major shared types. A comparison of the spoligotypes with those in databases for Scandinavian countries showed that 33% of the isolates belonged to an ill-defined T family, followed by the EAI (22%), Haarlem (20%), LAM (11%), Central Asian (5%), X (5%), and Beijing (4%) families. Both the highest number of cases and the proportion of clustered cases were observed in patients ages 15 to 39 years. Nearly 10% of the isolates were resistant to one or more drugs (essentially limited to isoniazid monoresistance). However, none of the strains were multidrug resistant. Data on the geographic origins of the patients showed that more than two-thirds of the clustered patients with tuberculosis were foreign-born individuals or refugees. These results are explained on the basis of both the historical links within specific countries and recently imported cases of tuberculosis into Sweden.
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| 4. |
- Burguière, Adeline, et al.
(författare)
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LosA, a key glycosyltransferase involved in the biosynthesis of a novel family of glycosylated acyltrehalose lipooligosaccharides from Mycobacterium marinum.
- 2005
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Ingår i: The Journal of biological chemistry. - 0021-9258. ; 280:51, s. 42124-33
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Tidskriftsartikel (refereegranskat)abstract
- Members of the genus Mycobacterium are characterized by cell envelopes rich in unusual free lipids, interacting with a covalently anchored mycolyl-arabinogalactan matrix. Previous studies have shown that Mycobacterium marinum produces large amounts of a diacylglycosylphenolphthiocerol, "phenolic" glycolipid. When cultivated on liquid Sauton medium, traces of a polar lipooligosaccharide (LOS) glycolipid antigen were also previously indicated. In this study, it was found that growth of the type strain of M. marinum on solid Sauton or Middlebrook 7H10 agar gave substantial, but different, amounts of a family of four major trehalose-based LOSs. The core pentasaccharide LOS-I was a rhamnosyl diglucosyl-acylated trehalose. The heptasaccharide, LOS-II, was derived from LOS-I by adding xylose accompanied by a novel sugar (X); repeated addition of this sugar unit X gave the octasaccharide LOS-III. LOS-IV has a decasaccharide component with two additional unusual sugar units, YZ. In a recent study (Alexander, D. C., Jones, J. R., Tan, T., Chen, J. M., and Liu, J. (2004) J. Biol. Chem. 279, 18824-18833), chromatographically similar glycolipids were assigned to the family of phosphatidylinositol mannosides (PIMs) and a "PimF" (Rv1500) glycosyltransferase implicated in the conversion of a supposed "PIM5" to a "PIM7." The present study indicates that these putative PIMs are in fact members of the phosphorus-free LOS family of glycolipids and that the protein product of Rv1500, which we have now termed LosA, is a glycosyltransferase involved in transferring sugars to LOS-III to form LOS-IV of M. marinum.
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| 5. |
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| 6. |
- Fjällbrant, Harald, 1961, et al.
(författare)
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BCG scar and tuberculin reactivity in children and adults.
- 2008
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Ingår i: Scandinavian journal of infectious diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 40:5, s. 387-92
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Tidskriftsartikel (refereegranskat)abstract
- Bacille Calmette-Guérin (BCG) vaccination generally leads to scar formation and tuberculin skin test (TST) reactivity. This study aimed at analysing these 2 parameters and their correlation in a setting with a low prevalence of tuberculosis. Retrospectively, we analysed 314 children and 390 adults living in Sweden and known from records or individual recall to have undergone BCG vaccination. A BCG scar was present in 161 (51%) of the children and in 340 (87%) of the adults. Among children with a scar, 94 (58%) were TST-positive (>/=6 mm) compared to 23 (15%) of 154 children lacking a visible scar. Among adults with a scar, 258 (76%) were TST- positive compared to 23 (46%) of 50 with no scar. Out of 152 non-vaccinated adults, 142 (94.4%) were TST-negative. When 175 TST-negative health care students were BCG-vaccinated in a prospective part of the study, 174 (99%) were found to develop a scar. In essence, the study showed a positive correlation between scar presence and TST reactivity. Furthermore, BCG vaccination of adults in the present setting resulted in consistent scar formation, while scar prevalence in previously vaccinated children was low.
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| 7. |
- Fjällbrant, Harald, 1961, et al.
(författare)
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Primary vaccination and revaccination of young adults with BCG: a study using immunological markers.
- 2007
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Ingår i: Scandinavian journal of infectious diseases. - : Informa UK Limited. - 0036-5548 .- 1651-1980. ; 39:9, s. 792-8
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Tidskriftsartikel (refereegranskat)abstract
- Questions have been raised about the effectiveness of Bacille Calmette-Guérin (BCG) vaccination against tuberculosis (TB) in adults. We therefore analysed the immune response after BCG vaccination in primary-vaccinated and revaccinated young adults. 31 tuberculin skin test (TST) negative healthy students were BCG-vaccinated; 15 were primary-vaccinated and 16 revaccinated. Tuberculin-induced lymphocyte transformation (LT) and cytokine production of peripheral blood mononuclear cells were studied before BCG vaccination, as well as after 2 months and 1 y. In the primary-vaccinated as well as the revaccinated group the LT response increased after 2 months and remained significantly higher than baseline values after 1 y. In both groups the interferon-gamma (IFN-gamma) levels increased significantly after 2 months and the increase was maintained after 1 y. LT increased more in the revaccinated group than in the primary-vaccinated group, while the increase in IFN-gamma response did not differ between the 2 groups. Both primary vaccination and revaccination of TST negative young adults caused a significant increase in the T-helper 1-type immune response, suggesting a protective effect against TB. The present in vitro results thus support the policy in several low-endemic countries of primary vaccination as well as revaccination of young adults at risk of TB exposure.
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| 8. |
- Fjällbrant, Harald, 1961, et al.
(författare)
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Tuberculin skin test reactivity of health care students in a country with a low prevalence of tuberculosis.
- 2010
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Ingår i: The international journal of tuberculosis and lung disease. - 1815-7920. ; 14:10, s. 1272-1279
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Tidskriftsartikel (refereegranskat)abstract
- SETTING: Health care students in Sweden. OBJECTIVE: To analyse the distribution of tuberculin skin test (TST) reactions and epidemiological factors related to TST reactivity. DESIGN: TST reactivity was analysed in 1190 students. A linear regression model was created for the relative contribution of background factors of TST reactivity. A subgroup of 287 non-vaccinated subjects was comparatively skin-tested with Mycobacterium avium sensitin and tuberculin. RESULTS: Among non-bacille Calmette-Guérin (BCG) vaccinated students, 91% had no TST reaction (0 mm induration) and reactions of ≥10 mm were found in 2.9%, whereas 34% of BCG-vaccinated students had no TST reaction and 42% had reactions of ≥10 mm. The expected contribution to TST reactivity was 6.0 mm for a history of BCG vaccination, 3.0 mm for a country of birth with medium/high incidence of TB and 1.6 mm per 10 years of age. The sensitin reactions exceeded the TST reactions by ≥3 mm in 52% of the comparatively tested subjects with TST reactions of ≥1 mm. CONCLUSION: BCG vaccination, cross-reactivity with non-tuberculous mycobacteria, geographic origin and age had a decisive influence on TST reactivity. Most non-vaccinated health care students were non-reactive, which highlights the need to organise preventive measures in settings where TB exposure is expected.
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| 9. |
- Fäldt, Jenny, 1971, et al.
(författare)
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Activation of human neutrophils by mycobacterial phenolic glycolipids.
- 1999
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Ingår i: Clinical and experimental immunology. - 0009-9104. ; 118:2, s. 253-60
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Tidskriftsartikel (refereegranskat)abstract
- The interaction between mycobacterial phenolic glycolipids (PGLs) and phagocytes was studied. Human neutrophils were allowed to interact with each of four purified mycobacterial PGLs and the neutrophil production of reactive oxygen metabolites was followed kinetically by luminol-/isoluminol-amplified chemiluminescence. The PGLs from Mycobacterium tuberculosis and Mycobacterium kansasii, respectively, were shown to stimulate the production of oxygen metabolites, while PGLs from Mycobacterium marinum and Mycobacterium bovis BCG, respectively, were unable to induce an oxidative response. Periodate treatment of the M. tuberculosis PGL decreased the production of oxygen radicals, showing the importance of the PGL carbohydrate moiety for the interaction. The activation, however, could not be inhibited by rhamnose or fucose, indicating a complex interaction which probably involves more than one saccharide unit. This is in line with the fact that the activating PGLs from M. tuberculosis and M. kansasii contain tri- and tetrasaccharides, respectively, while the nonactivating PGLs from M. marinum and M. bovis BCG each contain a monosaccharide. The complement receptor 3 (CR3) has earlier been shown to be of importance for the phagocyte binding of mycobacteria, but did not appear to be involved in the activation of neutrophils by PGLs. The subcellular localization of the reactive oxygen metabolites formed was related to the way in which the glycolipids were presented to the cells.
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| 10. |
- Fäldt, Jenny, 1971, et al.
(författare)
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Priming of human neutrophils by mycobacterial lipoarabinomannans: role of granule mobilisation.
- 2001
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Ingår i: Microbes and infection. - 1286-4579. ; 3:13, s. 1101-9
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Tidskriftsartikel (refereegranskat)abstract
- Lipoarabinomannans (LAMs) from mycobacteria were investigated concerning their effect on human neutrophils. Two types of LAM, the mannose-capped ManLAM from the virulent Mycobacterium tuberculosis H37Rv and the mannose-lacking AraLAM from a rapidly growing mycobacterial strain were used. Neither AraLAM nor ManLAM induced any significant direct activation of the NADPH-oxidase. Both LAMs, however, primed the neutrophils so that subsequent stimulation with the peptide chemoattractants fMet-Leu-Phe (fMLF), Trp-Lys-Tyr-Met-Val-DMet (WKYMVm) and the mammalian lactose-binding lectin galectin-3 resulted in a markedly enhanced oxidative response. The LAM-induced priming was accompanied by an increased exposure of complement receptors 1 and 3 as well as the formyl peptide receptor on the neutrophil surface, suggesting that the enhanced oxidative response could be due to upregulation of receptors on the cell surface as a result of granule mobilisation. Since LAM-primed neutrophils released 65% of the cell content of gelatinase but showed no increased release of vitamin B(12)-binding protein, mobilisation of the gelatinase granules rather than the specific granules is concluded to be responsible for the priming effects. This is in agreement with the subcellular localisation of receptors for fMLF, WKYMVm, as well as galectin-3, which are stored in the secretory vesicles and gelatinase granules. The priming effect appeared very similar to that of Escherichia coli lipopolysaccharide, and since no differences in activity could be detected between AraLAM and ManLAM, we hypothesize that the lipid anchor of the LAM is responsible for the priming effects.
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| 11. |
- Fäldt, Jenny, 1971, et al.
(författare)
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The phagocyte chemiluminescence paradox: luminol can act as an inhibitor of neutrophil NADPH-oxidase activity.
- 1999
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Ingår i: Luminescence : the journal of biological and chemical luminescence. - 1522-7235. ; 14:3, s. 153-60
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Tidskriftsartikel (refereegranskat)abstract
- The chemiluminescence system amplified by luminol or isoluminol is a sensitive and widely used method for determination of respiratory burst products generated by the NADPH-oxidase in phagocytes. The present study shows that luminol, but not isoluminol, can inhibit the release of oxygen metabolites generated by human neutrophil NADPH-oxidase. The difference in structure between luminol and isoluminol (rendering luminol more lipophilic than isoluminol, and thereby membrane-permeable), is suggested to determine indirectly whether or not the molecule is inhibitory. Luminol was shown to have an increased inhibitory effect after preincubation of neutrophils on a surface of aggregated IgG, suggesting that the cells can be transferred from a 'luminol-insensitive' to a 'luminol-sensitive' state. Since luminol had no inhibitory effect in a cell-free NADPH-oxidase system, it is likely that it interferes with the signal transduction pathway, leading to assembly and/or activation of the oxidase. As a consequence of the present results, showing that luminol but not isoluminol can inhibit NADPH-oxidase activity, we suggest that isoluminol is used in future studies of superoxide anion release from phagocytes.
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| 12. |
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| 13. |
- Jankute, M., et al.
(författare)
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The role of hydrophobicity in tuberculosis evolution and pathogenicity
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- The evolution of tubercle bacilli parallels a route from environmental Mycobacterium kansasii, through intermediate "Mycobacterium canettii", to the modern Mycobacterium tuberculosis complex. Cell envelope outer membrane lipids change systematically from hydrophilic lipooligosaccharides and phenolic glycolipids to hydrophobic phthiocerol dimycocerosates, di-and pentaacyl trehaloses and sulfoglycolipids. Such lipid changes point to a hydrophobic phenotype for M. tuberculosis sensu stricto. Using Congo Red staining and hexadecane-aqueous buffer partitioning, the hydrophobicity of rough morphology M. tuberculosis and Mycobacterium bovis strains was greater than smooth "M. canettii" and M. kansasii. Killed mycobacteria maintained differential hydrophobicity but defatted cells were similar, indicating that outer membrane lipids govern overall hydrophobicity. A rough M. tuberculosis H37Rv Delta papA1 sulfoglycolipid-deficient mutant had significantly diminished Congo Red uptake though hexadecane-aqueous buffer partitioning was similar to H37Rv. An M. kansasii, Delta MKAN27435 partially lipooligosaccharide-deficient mutant absorbed marginally more Congo Red dye than the parent strain but was comparable in partition experiments. In evolving from ancestral mycobacteria, related to "M. canettii" and M. kansasii, modern M. tuberculosis probably became more hydrophobic by increasing the proportion of less polar lipids in the outer membrane. Importantly, such a change would enhance the capability for aerosol transmission, affecting virulence and pathogenicity.
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| 14. |
- Jönsson, Bodil, 1959, et al.
(författare)
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Evaluation of the Cobas TaqMan MTB test for detection of Mycobacterium tuberculosis complex.
- 2015
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Ingår i: Infectious diseases (London, England). - : Informa UK Limited. - 2374-4243 .- 2374-4235. ; 47:4, s. 231-6
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Tidskriftsartikel (refereegranskat)abstract
- The Cobas TaqMan MTB assay is used for rapid detection of the Mycobacterium tuberculosis complex (MTC) in clinical samples. It is only validated for respiratory samples, but is often requested by physicians for non-respiratory specimens. The aim of this study was therefore to evaluate the performance of this assay in clinical praxis in a country with low prevalence of tuberculosis (TB).
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| 15. |
- Jönsson, Bodil, 1959, et al.
(författare)
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Molecular epidemiology of Mycobacterium abscessus, with focus on cystic fibrosis.
- 2007
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Ingår i: Journal of clinical microbiology. - 0095-1137. ; 45:5, s. 1497-504
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Tidskriftsartikel (refereegranskat)abstract
- Mycobacterium abscessus has been isolated increasingly often from the respiratory tracts of cystic fibrosis (CF) patients. It is not known whether these organisms are transmitted from person to person or acquired from environmental sources. Here, colony morphology and pulsed-field gel electrophoresis (PFGE) pattern were examined for 71 isolates of M. abscessus derived from 14 CF patients, three non-CF patients with chronic respiratory M. abscessus infection or colonization, one patient with mastoiditis, and four patients with infected wounds, as well as for six isolates identified as environmental contaminants in various clinical specimens. Contaminants and wound isolates mainly exhibited smooth colony morphology, while a rough colony phenotype was significantly associated with chronic airway colonization (P=0.014). Rough strains may exhibit increased airway-colonizing capacity, the cause of which remains to be determined. Examination by PFGE of consecutive isolates from the same patient showed that they all represented a single strain, even in cases where both smooth and rough isolates were present. When PFGE patterns were compared, it was shown that 24 patients had unique strains, while four patients harbored strains indistinguishable by PFGE. Two of these were siblings with CF. The other two patients, one of whom had CF, had not had contact with each other or with the siblings. Our results show that most patients colonized by M. abscessus in the airways have unique strains, indicating that these strains derive from the environment and that patient-to-patient transmission rarely occurs.
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| 16. |
- Jönsson, Bodil, 1959, et al.
(författare)
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Non-tuberculous mycobacteria and their surface lipids efficiently induced IL-17 production in human T cells
- 2012
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Ingår i: Microbes and Infection. - : Elsevier BV. - 1286-4579. ; 14:13, s. 1186-1195
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Tidskriftsartikel (refereegranskat)abstract
- Interleukin-17 (IL-17) is produced by a subset of CD4(+) T helper (Th) lymphocytes known as Th17 cells. In humans, IL-1 beta, enhanced by IL-6 and IL-23 is crucial for differentiation of these cells. IL-17 evokes inflammation and is involved in host defence against microorganisms, although little is known about its role in diseases caused by non-tuberculous mycobacteria. The genus Mycobacterium contains both obligate and opportunistic pathogens as well as saprophytes, and the mycobacterial cell envelope is unique in its abundance of lipids. Here we investigated IL-17 and IL-23 production in human PBMC in response to intact UV-inactivated mycobacteria and mycobacterial surface lipids from two opportunistic (Mycobacterium avium and Mycobacterium abscessus) and one generally non-pathogenic (Mycobacterium gordonae) species. Representative Gram-positive (Enterococcus faecalis, Streptococcus mitis) and Gram-negative (Escherichia coli) bacteria were included as controls. Intact mycobacteria induced production of large amounts of IL-17, while IL-17 responses to control bacteria were negligible. Purified CD4(+) T cells, but not CD4-depleted cell fractions, produced this IL-17. Isolated mycobacterial surface lipids induced IL-17, but not IL-23 production. The ability of the non-tuberculous mycobacteria to induce IL-17 production in CD4(+) T cells was the same regardless of the pathogenic potential of the particular mycobacterial species.
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| 17. |
- Jönsson, Bodil, 1959, et al.
(författare)
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Phagocytosis and cytokine response to rough and smooth colony variants of Mycobacterium abscessus by human peripheral blood mononuclear cells.
- 2013
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Ingår i: APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. - : Wiley. - 1600-0463. ; 121:1, s. 45-55
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Tidskriftsartikel (refereegranskat)abstract
- Mycobacterium abscessus is a non-tuberculous mycobacteria able to cause opportunistic infections in selected patient groups. During the last decades it has emerged as a cause of chronic pulmonary infection in patients with cystic fibrosis (CF). M. abscessus strains exhibit either smooth or rough colony morphology. Strains exhibiting the rough phenotype more often cause pulmonary infections in CF patients than did the smooth ones. Here, we examined phagocytosis and production of cytokines by human peripheral blood mononuclear cells, in response to M. abscessus strains with smooth and rough colony phenotype. The rough isolates all formed multicellular cords, similar to what is observed in Mycobacterium tuberculosis. Monocytes were generally unable to internalize these rough cord isolates, in contrast with the smooth ones. Furthermore, the rough M. abscessus strains induced a distinct cytokine profile differing from that induced by the smooth ones. Rough isolates induced significantly less IL-10 and tumour necrosis factor compared to smooth strains, but more IL-1β. Both varieties induced equal amounts of IFN-γ, IL-17, IL-23, IL-6, IL-8 and equally little IL-12. The ability to withstand phagocytosis might be a virulence factor contributing to the capacity of rough M. abscessus strains to give persistent pulmonary infections.
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| 18. |
- Jönsson, Bodil, 1959, et al.
(författare)
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TB can be detected with PCR – but only in smearpositive respiratory samples : Tbc kan påvisas med PCR – men bara i direktpositiva luftvägsprov
- 2018
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Ingår i: Lakartidningen. - 0023-7205. ; 115:1-2
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Forskningsöversikt (refereegranskat)abstract
- Unnecessary and inappropriate clinical requests represent a great waste of time and money and may also result in false diagnoses. PCR techniques, such as Cobas TaqMan MTB, are used for rapid detection of tuberculosis (TB). These assays are only validated for respiratory specimens, but they are commonly requested also for non-respiratory specimens. These assays perform well in smear-positive respiratory samples, while the sensitivities are quite unsatisfactory for both respiratory and non-respiratory smearnegatives samples. The specificity is high and it is possible to rapidly distinguish between TB and infections caused by environmental mycobacteria. The analyses demonstrate, furthermore, that PCR assays cannot be used to evaluate treatment, detect relapses or exclude TB. Nor can these assays be used to evaluate contagiousness or to screen for TB. © 2017, Swedish Medical Association. All rights reserved.
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| 19. |
- Jönsson, Bodil, 1959, et al.
(författare)
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The surface lipids of non-tuberculous mycobacteria suppress production of phagocyte activating cytokines in human peripheral blood mononuclear cells
- 2012
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Ingår i: Microbes and Infection. - : Elsevier BV. - 1286-4579. ; 14:9, s. 768-777
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Tidskriftsartikel (refereegranskat)abstract
- The genus Mycobacterium includes obligate pathogens as well as opportunistic and non-pathogenic species ubiquitous in the environment. Mycobacteria have a unique cell wall abundant in lipids. Here we investigated cytokine production by human peripheral blood mononuclear cells (PBMC) in response to the opportunistic mycobacteria Mycobacterium avium and Mycobacterium abscessus, the non-pathogenic Mycobacterium gordonae and extracted surface lipids from the three species. The cytokine response elicited by mycobacteria, regardless of their pathogenic potential, differed distinctly from that induced by control Gram-positive (Enterococcus faecalis, Streptococcus mitis) and Gram-negative (Escherichia coli) bacteria. Mycobacteria induced no IL-12 and less TNF and IFN-γ compared with conventional Gram-positive bacteria. IL-10 was induced by all the mycobacteria and this production was partly responsible for the down-regulation of IL-12 and IFN-γ. The capacity of the Gram-positive bacterium E. faecalis to induce IL-12, as well as TNF and IFN-γ, in human PBMCs was strongly reduced when mycobacterial lipids were added. The mycobacterial surface lipids down-regulated the production of IL-12 and IFN-γ without eliciting IL-10 production. Our results show that mycobacteria evade triggering production of phagocyte activating cytokines (IL-12, TNF and IFN-γ) and that the mycobacterial cell wall surface lipids may play a significant role in this process.
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| 20. |
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| 21. |
- Larsson, Lars-Olof, et al.
(författare)
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Nontuberculous Mycobacterial Diseases in Humans
- 2019
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Ingår i: Nontuberculous Mycobacteria (NTM) - Microbiolocical, Clinical and Geografical distribution) / Editors: Ali Akbar and Parissa Farnia. - : Academic Press. - 9780128146927 ; , s. 101-119
-
Bokkapitel (refereegranskat)abstract
- The number of patients infected with nontuberculous mycobacteria (NTM) is increasing and presents severe health problems. NTM infections in children are not uncommon and differ in several aspects from NTM infections in adults. In children, lymph nodes are most often infected, while lung infections dominate among adults. Thus, this chapter on NTM infections will focus on infections in children and pulmonary infections in adults. The reason why NTM diseases have been more commonly recognized is partly due to increased awareness and improved diagnostic methods. In addition, the number of patients with impaired resistance to infections has increased and such conditions are important risk factors for developing NTM disease. However, many NTM patients, particularly children, have no known predisposing condition. In addition, spontaneous resolution is common among children. Diagnosis and treatment are challenging since many patients suffer from other diseases and many NTM are resistant to commonly used drugs. Therapy is, therefore, generally complex and prolonged and side effects are common.
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| 22. |
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| 23. |
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| 24. |
- Petrini, Björn, et al.
(författare)
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Lungsjukdom med icke-tuberkulösa mykobakterier
- 2015
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Ingår i: Lungmedicin. Redaktörer: Thomas Sandström, Anders Eklund. - Lund : Studentlitteratur. - 9789144084190 ; , s. 303-310
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Bokkapitel (refereegranskat)
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| 25. |
- Ridell, Malin, 1942
(författare)
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New options in Tuberculosis Care: Visions for the future are crucial for controlling the disease.
- 2016
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Ingår i: International journal of mycobacteriology. - : Medknow. - 2212-554X .- 2212-5531. ; 5:Suppl 1
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Forskningsöversikt (refereegranskat)abstract
- The current strategies for controlling tuberculosis (TB) are not sufficient. Improved prophylactic and diagnostic tools are imperative, being crucial for decreasing TB incidence and mortality and for preventing outbreaks. Furthermore, new and better drugs are badly needed, particularly considering the increase in cases with multidrug-resistant strains. The current TB vaccine-the Bacillus Calmette-Guérin vaccine-has a preventive impact on disseminated TB in children, but little effect on the most common form of TB, that is, lung TB in adults and young adults. For many years extensive scientific efforts have been made in order to develop new vaccines against TB that are better and more effective than Bacillus Calmette-Guérin. No such vaccine exists, however, to date. During the last few years it has become increasingly clear that TB patients can be infected with more than one strain and that a previous TB infection increases rather than decreases the risk for getting a new one. Mycobacterium tuberculosis organisms are thus not capable of inducing protective immunity to such an extent that a new TB infection is prevented. This phenomenon highlights the problems of developing effective vaccines against TB. A new TB vaccine based on general immunological protection models would in all probability only have a limited capacity to hamper TB incidence and mortality. The question whether or not it is feasible to make a vaccine of sufficient efficacy must therefore be discussed. Prophylaxis is practically always far better than therapy and we all wish we had an effective TB vaccine. However, considering the problems with vaccines, scientific efforts could well focus on developing new therapies rather than new vaccines. New scientific approaches are highly necessary and we need ideas and visions. Some examples of recent projects will hereby be presented. One study concerns the mycobacterial cell envelope and its unique macromolecules as targets for new drugs. Another study concerns new ways of administrating the drugs which could enhance the effects of new as well as of already available drugs. In addition, what can be learnt from cancer therapy-is supporting the patient's own defense by immune modularly methods a possible approach? We also need to look back since ample knowledge on TB has been assembled during many years. Unfortunately some of this valuable knowledge is about to be forgotten, particularly, the experience from the time when TB was an incurable disease.
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| 26. |
- Svensson, Erik, 1959, et al.
(författare)
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Impact of immigration on tuberculosis epidemiology in a low-incidence country.
- 2011
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Ingår i: Clinical microbiology and infection. - : Elsevier BV. - 1469-0691 .- 1198-743X. ; 17:6, s. 881-887
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT: Mycobacterium tuberculosis strains from 349 patients were isolated in western Sweden during the years 2001-2005. Only 26% of the tuberculosis (TB) patients were born in Sweden. All the others were born in any of 42 different countries; 17% in other European countries, 28% in Africa, 16% in Asia, 11% in the Middle East, and 2% in South America. The mean age of the Swedish-born patients was 67years, while the mean age among the foreign-born patients was 37years. The male/female ratio was 1.6 among the Swedes and 0.9 among those born abroad. Extrapulmonary manifestations of TB were most common among patients born in Africa while lung infections without extrapulmonary manifestations were most common in patients born in Europe, including Sweden. Spoligotyping showed that patients with T or Beijing strains had more pulmonary TB than extrapulmonary TB, while patients with EAI and CAS strains had a high proportion of extrapulmonary TB. The ancestral and/or evolutionary older PGG1 strains were more often isolated from the foreign-born patients than from the Swedish-born patients, who had strains generally being of the evolutionary recent genogroups PGG2/PGG3. We conclude that immigration from countries with a high incidence of TB has a strong impact on the TB epidemiology in western Sweden, a finding that should be taken into account by TB control strategists when developing programmes for eradication of TB in low prevalence settings.
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