| 1. |
- Collste, O., et al.
(författare)
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Myocardial infarction with normal coronary arteries is common and associated with normal findings on cardiovascular magnetic resonance imaging: results from the Stockholm Myocardial Infarction with Normal Coronaries study
- 2013
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Ingår i: Journal of Internal Medicine. - : Wiley. - 1365-2796 .- 0954-6820. ; 273:2, s. 189-196
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Tidskriftsartikel (refereegranskat)abstract
- Collste O, Sorensson P, Frick M, Agewall S, Daniel M, Henareh L, Ekenback C, Eurenius L, Guiron C, Jernberg T, Hofman-Bang C, Malmqvist K, Nagy E, Arheden H, Tornvall P (Sodersjukhuset, Stockholm; Karolinska Hospital, Karolinska Institutet, Stockholm, Sweden; University of Oslo, Oslo, Norway; Sankt Goran Hospital Capio, Karolinska Institutet, Stockholm; Huddinge, Stockholm; Danderyd Hospital, Karolinska Institutet, Stockholm; and Skane University Hospital, Lund University, Lund, Sweden). Myocardial infarction with normal coronary arteries is common and associated with normal findings on cardiovascular magnetic resonance imaging: results from the Stockholm Myocardial Infarction with Normal Coronaries study. J Intern Med 2013; 273: 189-196. Objectives Myocardial infarction with angiographically normal coronary arteries (MINCA) is an important subtype of myocardial infarction; however, the prevalence, underlying pathophysiology, prognosis and optimal management of this condition are still largely unknown. Cardiovascular magnetic resonance (CMR) imaging has the potential to clarify the underlying pathology in patients with MINCA. The objective of this study was to investigate the diagnostic value of CMR imaging in this group of patients. Design The prospective, multicentre, observational Stockholm Myocardial Infarction with Normal Coronaries (SMINC) study. Setting Coronary care units in the Stockholm metropolitan area. Subjects Patients between 35 and 70 years of age with MINCA were consecutively included in the screening phase of the SMINC study. All patients had a typical clinical presentation, fulfilling the universal definition of myocardial infarction and had normal coronary angiography finding. Patients with known structural or coronary heart disease or other known causes of elevated troponin levels were excluded. Results In total, 176 patients with MINCA were screened from 2007 to 2011. Of these, 152 underwent CMR imaging. The investigation was performed a median of 12 (interquartile range 628) days after hospital admission; 67% of the findings were normal, whereas 19% of patients had signs of myocardial necrosis and 7% had signs of myocarditis. The remaining patients (7%) had either unrecognized hypertrophic cardiomyopathy or could not be classified. Conclusion In this consecutive series of patients with MINCA, CMR imaging may help to differentiate between those with myocarditis, myocardial necrosis and normal myocardium. The incidence of MINCA was higher than previously reported. After excluding cases of myocarditis, MINCA consists of a large group of patients with normal CMR imaging results and a smaller group with myocardial necrosis. The aetiologies of these different imaging findings need to be explored.
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| 2. |
- Neumann, J. T., et al.
(författare)
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Application of High-Sensitivity Troponin in Suspected Myocardial Infarction
- 2019
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Ingår i: New England Journal of Medicine. - : MASSACHUSETTS MEDICAL SOC. - 0028-4793 .- 1533-4406. ; 380:26, s. 2529-2540
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundData regarding high-sensitivity troponin concentrations in patients presenting to the emergency department with symptoms suggestive of myocardial infarction may be useful in determining the probability of myocardial infarction and subsequent 30-day outcomes. MethodsIn 15 international cohorts of patients presenting to the emergency department with symptoms suggestive of myocardial infarction, we determined the concentrations of high-sensitivity troponin I or high-sensitivity troponin T at presentation and after early or late serial sampling. The diagnostic and prognostic performance of multiple high-sensitivity troponin cutoff combinations was assessed with the use of a derivation-validation design. A risk-assessment tool that was based on these data was developed to estimate the risk of index myocardial infarction and of subsequent myocardial infarction or death at 30 days. ResultsAmong 22,651 patients (9604 in the derivation data set and 13,047 in the validation data set), the prevalence of myocardial infarction was 15.3%. Lower high-sensitivity troponin concentrations at presentation and smaller absolute changes during serial sampling were associated with a lower likelihood of myocardial infarction and a lower short-term risk of cardiovascular events. For example, high-sensitivity troponin I concentrations of less than 6 ng per liter and an absolute change of less than 4 ng per liter after 45 to 120 minutes (early serial sampling) resulted in a negative predictive value of 99.5% for myocardial infarction, with an associated 30-day risk of subsequent myocardial infarction or death of 0.2%; a total of 56.5% of the patients would be classified as being at low risk. These findings were confirmed in an external validation data set. ConclusionsA risk-assessment tool, which we developed to integrate the high-sensitivity troponin I or troponin T concentration at emergency department presentation, its dynamic change during serial sampling, and the time between the obtaining of samples, was used to estimate the probability of myocardial infarction on emergency department presentation and 30-day outcomes.
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| 3. |
- Skoglund, A., et al.
(författare)
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Functional analysis of the M.HpyAIV DNA methyltransferase of Helicobacter pylori
- 2007
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Ingår i: Journal of Bacteriology. - 0021-9193 .- 1098-5530. ; 189:24, s. 8914-8921
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Tidskriftsartikel (refereegranskat)abstract
- A large number of genes encoding restriction-modification (R-M) systems are found in the genome of the human pathogen Helicobacter pylori. R-M genes comprise approximately 10% of the strain-specific genes, but the relevance of having such an abundance of these genes is not clear. The type II methyltransferase (MTase) M.HpyAIV, which recognizes GANTC sites, was present in 60% of the H. pylori strains analyzed, whereof 69% were resistant to restriction enzyme digestion, which indicated the presence of an active MTase. H. pylori strains with an inactive M.HpyAIV phenotype contained deletions in regions of homopolymers within the gene, which resulted in premature translational stops, suggesting that M.HpyAIV may be subjected to phase variation by a slipped-strand mechanism. An M.HpyAIV gene mutant was constructed by insertional mutagenesis, and this mutant showed the same viability and ability to induce interleukin-8 in epithelial cells as the wild type in vitro but had, as expected, lost the ability to protect its self-DNA from digestion by a cognate restriction enzyme. The M.HpyAIV from H. pylori strain 26695 was overexpressed in Escherichia coli, and the protein was purified and was able to bind to DNA and protect GANTC sites from digestion in vitro. A bioinformatic analysis of the number of GANTC sites located in predicted regulatory regions of H. pylori strains 26695 and J99 resulted in a number of candidate genes. katA, a selected candidate gene, was further analyzed by quantitative real-time reverse transcription-PCR and shown to be significantly down-regulated in the M.HpyAIV gene mutant compared to the wild-type strain. This demonstrates the influence of M.HpyAIV methylation in gene expression.
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| 4. |
- Agewall, S, et al.
(författare)
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Risk factors for myocardial infarction with normal coronary arteries and myocarditis compared with myocardial infarction with coronary artery stenosis
- 2012
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Ingår i: Angiology. - : SAGE Publications. - 1940-1574 .- 0003-3197. ; 63:7, s. 500-503
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Tidskriftsartikel (refereegranskat)abstract
- The interest and awareness of myocardial infarction with normal coronary arteries (MINCA) have increased recently due to the frequent use of coronary angiography, the description of Takotsubo stress cardiomyopathy, and new sensitive troponin analyses. The prevalence of MINCA in all patients with myocardial infarction (MI) was registered during a 3-month period in the Stockholm metropolitan area in Sweden. The results showed that MINCA is more common than previously thought (7%) and affecting one third of every woman with MI. Patients with myocarditis were younger and more often presented with signs of inflammation such as elevated C-reactive protein and fever. Myocarditis constitutes an important differential diagnosis for coronary artery disease. There is a need for larger studies of MINCA, including investigation with cardiac magnetic resonance imaging, to establish prevalence and pathological process in this important subgroup of MI.
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| 5. |
- Daniel, M., et al.
(författare)
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Prevalence of Anxiety and Depression Symptoms in Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries
- 2018
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Ingår i: American Journal of Medicine. - : Elsevier BV. - 0002-9343 .- 1555-7162. ; 131:9, s. 1118-1124
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Myocardial infarction with non-obstructive coronary arteries is a working diagnosis for several heart disorders. Previous studies on anxiety and depression in patients with myocardial infarction with non-obstructive coronary arteries are lacking. Our aim was to investigate the prevalence of anxiety and depression among patients with myocardial infarction with non-obstructive coronary arteries. METHODS: We included 99 patients with myocardial infarction with non-obstructive coronary arteries together with age- and sex-matched control groups who completed the Beck Depression Inventory and the Hospital Anxiety and Depression Scale (HADS) 3 months after the acute event. RESULTS: Using the Beck Depression Inventory, we found that the prevalence of depression in patients with myocardial infarction with non-obstructive coronary arteries (35%) was higher than in healthy controls (9%; P = .006) and similar to that of patients with coronary heart disease (30%; P = .954). Using the HADS anxiety subscale, we found that the prevalence of anxiety in patients with myocardial infarction with non-obstructive coronary arteries (27%) was higher than in healthy controls (9%; P = .002) and similar to that of patients with coronary heart disease (21%; P = .409). Using the HADS depression subscale, we found that the prevalence of depression in patients with myocardial infarction with non-obstructive coronary arteries (17%) was higher than in healthy controls (4%; P = .003) and similar to that of patients with coronary heart disease (13%; P = .466). Patients with myocardial infarction with non-obstructive coronary arteries and takotsubo syndrome scored higher on the HADS anxiety subscale than those without (P = .028). CONCLUSIONS: This is the first study on the mental health of patients with myocardial infarction with non obstructive coronary arteries to show that prevalence rates of anxiety and depression are similar to those in patients with coronary heart disease. (C) 2018 Elsevier Inc. All rights reserved.
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| 6. |
- Hua, Y., et al.
(författare)
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Molecular characteristics of eae-positive clinical Shiga toxin-producing Escherichia coli in Sweden
- 2020
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Ingår i: Emerging microbes & infections. - : Informa UK Limited. - 2222-1751. ; 9:1, s. 2562-2570
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Tidskriftsartikel (refereegranskat)abstract
- Shiga toxin (Stx)-producing Escherichia coli (STEC) can cause a wide range of symptoms from asymptomatic carriage, mild diarrhea to bloody diarrhea (BD) and hemolytic uremic syndrome (HUS). Intimin, encoded by the eae gene, also plays a critical role in STEC pathogenesis. Herein, we investigated the prevalence and genetic diversity of eae among clinical STEC isolates from patients with diarrhea, BD, HUS as well as from asymptomatic STEC-positive individuals in Sweden with whole-genome sequencing. We found that 173 out of 239 (72.4%) of clinical STEC strains were eae positive. Six eae subtypes (epsilon 1, gamma 1, beta 3, theta, zeta and rho) were identified eae and its subtype gamma 1 were significantly overrepresented in O157:H7 strains isolated from BD and HUS patients. epsilon 1 was associated with O121:H19 and O103:H2 strains, and beta 3 to O26:H11 strains. The combination of eae subtype gamma 1 and stx subtype (stx (2) or stx (1)+stx (2)) is more likely to cause severe disease, suggesting the possibility of using eae genotypes in risk assessment of STEC infection. In summary, this study demonstrated a high prevalence of eae in clinical STEC strains and considerable genetic diversity of eae in STEC strains in Sweden from 1994 through 2018, and revealed association between eae subtypes and disease severity.
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| 7. |
- Hua, Y., et al.
(författare)
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Molecular Characterization of the Enterohemolysin Gene (ehxA) in Clinical Shiga Toxin-Producing Escherichia coli Isolates
- 2021
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Ingår i: Toxins. - : MDPI AG. - 2072-6651. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Shiga toxin (Stx)-producing Escherichia coli (STEC) is an important foodborne pathogen with the ability to cause bloody diarrhea (BD) and hemolytic uremic syndrome (HUS). Little is known about enterohemolysin-encoded by ehxA. Here we investigated the prevalence and diversity of ehxA in 239 STEC isolates from human clinical samples. In total, 199 out of 239 isolates (83.26%) were ehxA positive, and ehxA was significantly overrepresented in isolates carrying stx(2a) + stx(2c) (p < 0.001) and eae (p < 0.001). The presence of ehxA was significantly associated with BD and serotype O157:H7. Five ehxA subtypes were identified, among which, ehxA subtypes B, C, and F were overrepresented in eae-positive isolates. All O157:H7 isolates carried ehxA subtype B, which was related to BD and HUS. Three ehxA groups were observed in the phylogenetic analysis, namely, group ? (ehxA subtype A), group II (ehxA subtype B, C, and F), and group (ehxA subtype D). Most BD- and HUS-associated isolates were clustered into ehxA group II, while ehxA group ? was associated with non-bloody stool and individuals >= 10 years of age. The presence of ehxA + eae and ehxA + eae + stx(2) was significantly associated with HUS and O157:H7 isolates. In summary, this study showed a high prevalence and the considerable genetic diversity of ehxA among clinical STEC isolates. The ehxA genotypes (subtype B and phylogenetic group II) could be used as risk predictors, as they were associated with severe clinical symptoms, such as BD and HUS. Furthermore, ehxA, together with stx and eae, can be used as a risk predictor for HUS in STEC infections.
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| 8. |
- Hua, Y., et al.
(författare)
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Whole-genome characterization of hemolytic uremic syndrome-causing Shiga toxin-producing Escherichia coli in Sweden
- 2021
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Ingår i: Virulence. - : Informa UK Limited. - 2150-5594 .- 2150-5608. ; 12:1, s. 1296-1305
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Tidskriftsartikel (refereegranskat)abstract
- Shiga toxin-producing Escherichia coli, a foodborne bacterial pathogen, has been linked to a broad spectrum of clinical outcomes ranging from asymptomatic carriage to fatal hemolytic uremic syndrome (HUS). Here, we collected clinical data and STEC strains from HUS patients from 1994 through 2018, whole-genome sequencing was performed to molecularly characterize HUS-associated STEC strains, statistical analysis was conducted to identify bacterial genetic factors associated with severe outcomes in HUS patients. O157:H7 was the most predominant serotype (57%) among 54 HUS-associated STEC strains, followed by O121:H19 (19%) and O26:H11 (7%). Notably, some non-predominant serotypes such as O59:H17 (2%) and O109:H21 (2%) also caused HUS. All O157:H7 strains with one exception belonged to clade 8. During follow-up at a median of 4years, 41% of the patients had renal sequelae. Fifty-nine virulence genes were found to be statistically associated with severe renal sequelae, these genes encoded type II and type III secretion system effectors, chaperones, and other factors. Notably, virulence genes associated with severe clinical outcomes were significantly more prevalent in O157:H7 strains. In contrast, genes related to mild symptoms were evenly distributed across all serotypes. The whole-genome phylogeny indicated high genomic diversity among HUS-STEC strains. No distinct cluster was found between HUS and non-HUS STEC strains. The current study showed that O157:H7 remains the main cause of STEC-associated HUS, despite the rising importance of other non-O157 serotypes. Besides, O157:H7 is associated with severe renal sequelae in the follow-up, which could be a risk factor for long-term prognosis in HUS patients. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
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| 9. |
- Karlsson, S. C. Hannah, et al.
(författare)
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Combining CAR T cells and the Bcl-2 family apoptosis inhibitor ABT-737 for treating B-cell malignancy
- 2013
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Ingår i: Cancer Gene Therapy. - : Springer Science and Business Media LLC. - 0929-1903 .- 1476-5500. ; 20:7, s. 386-393
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Tidskriftsartikel (refereegranskat)abstract
- B-cell malignancies upregulate the B-cell lymphoma 2 (Bcl-2) family inhibitors of the intrinsic apoptosis pathway, making them therapy resistant. However, small-molecule inhibitors of Bcl-2 family members such as ABT-737 restore a functional apoptosis pathway in cancer cells, and its oral analog ABT-263 (Navitoclax) has entered clinical trials. Gene engineered chimeric antigen receptor (CAR) T cells also show promise in B-cell malignancy, and as they induce apoptosis via the extrinsic pathway, we hypothesized that small-molecule inhibitors of the Bcl-2 family may potentiate the efficacy of CAR T cells by engaging both apoptosis pathways. CAR T cells targeting CD19 were generated from healthy donors as well as from pre-B-ALL (precursor-B acute lymphoblastic leukemia) patients and tested together with ABT-737 to evaluate apoptosis induction in five B-cell tumor cell lines. The CAR T cells were effective even if the cell lines exhibited different apoptosis resistance profiles, as shown by analyzing the expression of apoptosis inhibitors by PCR and western blot. When combining T-cell and ABT-737 therapy simultaneously, or with ABT-737 as a presensitizer, tumor cell apoptosis was significantly increased. In conclusion, the apoptosis inducer ABT-737 enhanced the efficacy of CAR T cells and could be an interesting drug candidate to potentiate T-cell therapy.
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| 10. |
- Kristensen, AMD, et al.
(författare)
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Design and rationale of the Danish trial of beta-blocker treatment after myocardial infarction without reduced ejection fraction: study protocol for a randomized controlled trial
- 2020
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Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 21:1, s. 415-
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundTreatment with beta-blockers is currently recommended after myocardial infarction (MI). The evidence relies on trials conducted decades ago before implementation of revascularization and contemporary medical therapy or in trials enrolling patients with heart failure or reduced left ventricular ejection fraction (LVEF ≤ 40%). Accordingly, the impact of beta-blockers on mortality and morbidity following acute MI in patients without reduced LVEF or heart failure is unclear.Methods/designThe Danish trial of beta-blocker treatment after myocardial infarction without reduced ejection fraction (DANBLOCK) is a prospective, randomized, controlled, open-label, non-blinded endpoint clinical trial designed to evaluate the efficacy of beta-blocker treatment in post-MI patients in the absence of reduced LVEF or heart failure. We will randomize 3570 patients will be randomized within 14 days of index MI to beta-blocker or control for a minimum of 2 years. The primary endpoint is a composite of all-cause mortality, recurrent MI, acute decompensated heart failure, unstable angina pectoris, or stroke. The primary composite endpoint will be assessed through locally reported and adjudicated endpoints supplemented by linkage to the Danish national registers. A number of secondary endpoints will be investigated including patient reported outcomes and cardiovascular mortality. Data from similar ongoing trials in Norway and Sweden will be pooled to perform an individual patient data meta-analysis.DiscussionDANBLOCK is a randomized clinical trial investigating the effect of long-term beta-blocker therapy after myocardial infarction in patients without heart failure and reduced LVEF. Results from the trial will add important scientific evidence to inform future clinical guidelines.Trial registrationClinicaltrials.gov,NCT03778554. Registered on 19 December 2018.European Clinical Trials Database,2018-002699-42, registered on 28 September 2018.
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| 11. |
- McNamara, R. L., et al.
(författare)
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International comparisons of the management of patients with non-ST segment elevation acute myocardial infarction in the United Kingdom, Sweden, and the United States: The MINAP/NICOR, SWEDEHEART/RIKS-HIA, and ACTION Registry-GWTG/NCDR registries
- 2014
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Ingår i: International Journal of Cardiology. - : Elsevier BV. - 0167-5273 .- 1874-1754. ; 175:2, s. 240-247
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To compare management of patients with acute non-ST segment elevation myocardial infarction (NSTEMI) in three developed countries with national ongoing registries. Background: Results from clinical trials suggest significant variation in care across the world. However, international comparisons in "real world" registries are limited. Methods: We compared the use of in-hospital procedures and discharge medications for patients admitted with NSTEMI from 2007 to 2010 using the unselective MINAP/NICOR [England and Wales (UK); n = 137,009], the unselective SWEDEHEART/RIKS-HIA (Sweden; n = 45,069), and the selective ACTION Registry-GWTG/NCDR [United States (US); n = 147,438] clinical registries. Results: Patients enrolled among the three registries were generally similar except those in the US who were younger but had higher rates of smoking, diabetes, hypertension, prior heart failure, and prior MI than in Sweden or in UK. Angiography and percutaneous coronary intervention (PCI) were performed more often in the US (76% and 44%) and Sweden (65% and 42%) relative to the UK (32% and 22%). Discharge betablockers were also prescribed more often in the US (89%) and Sweden (89%) than in the UK (76%). In contrast, discharge statins, angiotensin converting enzyme inhibitors/angiotensin receptor blockers (ACEI/ARB), and dual antiplatelet agents (among those not receiving PCI) were higher in the UK (92%, 79%, and 71%) than in the US (85%, 65%, 41%) and Sweden (81%, 69%, and 49%). Conclusions: The care for patients with NSTEMI differed substantially among the three countries. These differences in care among countries provide an opportunity for future comparative effectiveness research as well as identify opportunities for global quality improvement. (C) 2014 The Authors. Published by Elsevier Ireland Ltd.
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| 12. |
- Omerovic, E., et al.
(författare)
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Impact of COVID-19 pandemics on the incidence and mortality in Takotsubo syndrome : a report from Swedish Coronary Angiography and Angioplasty Registry
- 2023
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Ingår i: European Heart Journal. - : Oxford University Press. - 0195-668X .- 1522-9645. ; 44:Suppl. 2
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: The COVID-19 pandemic resulted in severe psychological, social, and economic stress. Countries applied different anti-pandemic strategies that substantially impacted citizens' psychosocial stress and health. Takotsubo syndrome (TS) is frequently triggered by emotional stress. Previous studies from the USA have reported a severalfold increase in TS incidence during pandemics.Purpose: To determine the incidence and outcomes of TS in Sweden before (2015-March 2020) and during (April 2020-December 2022) the pandemic.Methods: We assessed the incidence rate ratio (IRR) for all patients with TS referred for coronary angiography in Sweden using the nationwide Swedish Coronary Angiography and Angioplasty Registry. Incidence rate ratios (IRRs) before and during the pandemic were calculated with Poisson regression adjusted for age and sex. We evaluated mortality with multivariable Cox proportional hazards regression, which accounted for clustering of patients within hospitals. The following variables were used for adjustment: age, sex, diabetes, smoking status, hypertension, hyperlipidemia, previous myocardial infarction, and Killip class.Results: We identified 3,180 patients (2,128 [76.0%] women) hospitalized with TS during the study period; 2,189 (69%) pre-pandemic and 991 (31%) during the pandemic. The average age was 68.3 ± 11.2 years. The median follow-up time was 1250 days (IQR 562-1995). The crude all-cause mortality rate was 2.57% at 30 days and 15.5% after long-term follow-up. The incidence of TS was 11% lower during the pandemic compared with the pre-pandemic period (IRR 0.90, 95% CI 0.83-0.98, P=0.009, Fig. 1). We found no difference in 30-day mortality (adjusted HR 1.12, 95% CI 0.69-1.78, P= 0.642) or long-term mortality (adjusted HR 0.96, 95% CI 0.73-1.28, P= 0.816) among patients with TS between the pre-pandemic and pandemic periods. When only data after 2016 are used, we found no difference in TS incidence (IRR 1.00, 95% CI 0.92-1.08, P=1.00).Conclusions: In this observational study, the incidence of TS was lower during than before the pandemic but mortality was unchanged. The lower incidence of TS could be related to the specific anti-pandemic strategies applied at the national level in Sweden.
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| 22. |
- Bai, XN, et al.
(författare)
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Characterization of Clinical Escherichia coli Strains Producing a Novel Shiga Toxin 2 Subtype in Sweden and Denmark
- 2021
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Ingår i: Microorganisms. - : MDPI AG. - 2076-2607. ; 9:11
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Tidskriftsartikel (refereegranskat)abstract
- Shiga toxin (Stx) is the key virulence factor in the Shiga Toxin-Producing Escherichia coli (STEC), which can cause diarrhea and hemorrhagic colitis with potential life-threatening complications. There are two major types of Stx: Stx1 and Stx2. Several Stx1/Stx2 subtypes have been identified in E. coli, varying in sequences, toxicity and host specificity. Here, we report a novel Stx2 subtype (designated Stx2m) from three clinical E. coli strains isolated from diarrheal patients and asymptomatic carriers in Sweden and Denmark. The Stx2m toxin was functional and exhibited cytotoxicity in vitro. The two Swedish Stx2m-producing strains belonged to the same serotype O148:H39 and Multilocus Sequencing Typing (MLST) Sequence Type (ST) 5825, while the Danish strain belonged to the O96:H19 serotype and ST99 type. Whole-genome sequencing (WGS) data analysis revealed that the three Stx2m-producing strains harbored additional virulence genes and the macrolide resistance gene mdf (A). Our findings expand the pool of Stx2 subtypes and highlight the clinical significance of emerging STEC variants. Given the clinical relevance of the Stx2m-producing strains, we propose to include Stx2m in epidemiological surveillance of STEC infections and clinical diagnosis.
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| 23. |
- Bai, XN, et al.
(författare)
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Molecular Characterization and Comparative Genomics of Clinical Hybrid Shiga Toxin-Producing and Enterotoxigenic Escherichia coli (STEC/ETEC) Strains in Sweden
- 2019
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Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1, s. 5619-
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Tidskriftsartikel (refereegranskat)abstract
- Hybrid E. coli pathotypes are representing emerging public health threats with enhanced virulence from different pathotypes. Hybrids of Shiga toxin-producing and enterotoxigenic E. coli (STEC/ETEC) have been reported to be associated with diarrheal disease and hemolytic uremic syndrome (HUS) in humans. Here, we identified and characterized four clinical STEC/ETEC hybrids from diarrheal patients with or without fever or abdominal pain and healthy contact in Sweden. Rare stx2 subtypes were present in STEC/ETEC hybrids. Stx2 production was detectable in stx2a and stx2e containing strains. Different copies of ETEC virulence marker, sta gene, were found in two hybrids. Three sta subtypes, namely, sta1, sta4 and sta5 were designated, with sta4 being predominant. The hybrids represented diverse and rare serotypes (O15:H16, O187:H28, O100:H30, and O136:H12). Genome-wide phylogeny revealed that these hybrids exhibited close relatedness with certain ETEC, STEC/ETEC hybrid and commensal E. coli strains, implying the potential acquisition of Stx-phages or/and ETEC virulence genes in the emergence of STEC/ETEC hybrids. Given the emergence and public health significance of hybrid pathotypes, a broader range of virulence markers should be considered in the E. coli pathotypes diagnostics, and targeted follow up of cases is suggested to better understand the hybrid infection.
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