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Predictors of hypervirulent Klebsiella pneumoniae infections: a systematic review and meta-analysis.The Journal of Hospital Infection Apr 2023Hypervirulent Klebsiella pneumoniae (hvKp) infections confer notable morbidity and mortality. Differential diagnosis to determine whether the infections are caused by... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Hypervirulent Klebsiella pneumoniae (hvKp) infections confer notable morbidity and mortality. Differential diagnosis to determine whether the infections are caused by either the hvKp or classical K. pneumoniae (cKp) strain is particularly important for undertaking optimal clinical care and infection control efforts.
AIM
To identify and assess the potential predictors of hvKp infections.
METHODS
PubMed, Web of Science, and Cochrane Library databases were searched for all relevant publications from January 2000 to March 2022. The search terms included a combination of the following terms: (i) Klebsiella pneumoniae or K. pneumoniae and (ii) hypervirulent or hypervirulence. A meta-analysis of factors for which risk ratio was reported in three or more studies was conducted, and at least one statistically significant association was identified.
FINDINGS
In this systematic review of 11 observational studies, a total of 1392 patients with K. pneumoniae infection and 596 (42.8%) with hvKp strains were evaluated. In the meta-analysis, diabetes mellitus and liver abscess (pooled risk ratio: 2.61 (95% confidence interval: 1.79-3.80) and 9.04 (2.58-31.72), respectively; all P < 0.001) were predictors of hvKp infections.
CONCLUSION
For patients with a history of the abovementioned predictors, prudent management, including the search for multiple sites of infection and/or metastatic spread and the enforcement of an early and appropriate source control procedure, should be initiated in consideration of the potential presence of hvKp. We believe that this research highlights the urgent need for increasing clinical awareness of the management of hvKp infections.
Topics: Humans; Virulence Factors; Virulence; Klebsiella pneumoniae; Klebsiella Infections; Anti-Bacterial Agents
PubMed: 36813165
DOI: 10.1016/j.jhin.2023.02.005 -
Frontiers in Immunology 2020The term ocular microbiota refers to all types of commensal and pathogenic microorganisms present on or in the eye. The ocular surface is continuously exposed to the...
The term ocular microbiota refers to all types of commensal and pathogenic microorganisms present on or in the eye. The ocular surface is continuously exposed to the environment and harbors various commensals. Commensal microbes have been demonstrated to regulate host metabolism, development of immune system, and host defense against pathogen invasion. An unbalanced microbiota could lead to pathogenic microbial overgrowth and cause local or systemic inflammation. The specific antigens that irritate the deleterious immune responses in various inflammatory eye diseases remain obscure, while recent evidence implies a microbial etiology of these illnesses. The purpose of this review is to provide an overview of the literature on ocular microbiota and the role of commensal microbes in several eye diseases. In addition, this review will also discuss the interaction between microbial pathogens and host factors involved in intraocular inflammation, and evaluate therapeutic potential of targeting ocular microbiota to treat intraocular inflammation.
Topics: Animals; Eye; Eye Diseases; Humans; Immune System; Immunity; Inflammation; Microbiota
PubMed: 33424865
DOI: 10.3389/fimmu.2020.609765 -
World Journal of Gastroenterology Aug 2015To investigate the relationship between Helicobacter pylori (H. pylori) and mucin expression in gastric mucosa. (Meta-Analysis)
Meta-Analysis Review
AIM
To investigate the relationship between Helicobacter pylori (H. pylori) and mucin expression in gastric mucosa.
METHODS
English Medical literature searches were conducted for gastric mucin expression in H. pylori infected people vs uninfected people. Searches were performed up to December 31(th) 2014, using MEDLINE, PubMed, EMBASE, Scopus, and CENTRAL. Studies comparing mucin expression in the gastric mucosa in patients positive and negative for H. pylori infection, were included. Meta-analysis was performed by using Comprehensive meta-analysis software (Version 3, Biostat Inc., Englewood, NJ, United States). Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated compared mucin expression in individual studies by using the random effects model. Heterogeneity between studies was evaluated using the Cochran Q-test, and it was considered to be present if the Q-test P value was less than 0.10. I(2) statistic was used to measure the proportion of inconsistency in individual studies, with I(2) > 50% representing substantial heterogeneity. We also calculated a potential publication bias.
RESULTS
Eleven studies, which represent 53 sub-studies of 15 different kinds of mucin expression, were selected according to the inclusion criteria. Every kind of mucin has been considered as one study. When a specific mucin has been studied in more than one paper, we combined the results in a nested meta-analysis of this particular mucin: MUC2, MUC6, STn, Paradoxical con A, Tn, T, Type 1 chain mucin, LeA, SLeA, LeB, AB-PAS, MUC1, and MUC5AC. The odds ratio of mucin expression in random analysis was 2.33, 95%CI: 1.230-4.411, P = 0.009, higher expression in H. pylori infected patients. Odds ratio for mucin expression in H. pylori positive patients was higher for MUC6 (9.244, 95%CI: 1.567-54.515, P = 0.014), and significantly lower for MUC5AC (0.447, 95%CI: 0.211-0.949, P = 0.036). Thus, H. pylori infection may increase MUC6 expression and decrease MUC5AC expression by 924% and 52%, respectively.
CONCLUSION
H. pylori inhibits MUC5AC expression in the gastric epithelium, and facilitates colonization. In contrast, increased MUC6 expression may help inhibiting colonization, using MUC6 antibiotics properties.
Topics: Gastric Mucins; Gastric Mucosa; Helicobacter Infections; Helicobacter pylori; Host-Pathogen Interactions; Humans; Mucin 5AC; Mucin-6; Odds Ratio
PubMed: 26309370
DOI: 10.3748/wjg.v21.i31.9430 -
Journal of Clinical Anesthesia Dec 2016To review the clinical and basic science literature regarding Zika viral illness and highlight relevant findings for obstetric anesthesiologists. This review provides a... (Review)
Review
STUDY OBJECTIVES
To review the clinical and basic science literature regarding Zika viral illness and highlight relevant findings for obstetric anesthesiologists. This review provides a global review of Zika viral illness, transmission patterns, pathophysiology of disease, and anesthetic management of the parturient with Zika viral illness and associated comorbidities.
DESIGN
Systematic review.
SETTING
Large academic hospital.
SUBJECTS
None.
INTERVENTIONS
None.
MEASUREMENTS
None.
MAIN RESULTS
None.
CONCLUSION
With the rapid spread of Zika virus and expected increase of spread in the summer of 2016, this review provides anesthesiologists with current recommendations, physiologic alterations, and anesthetic considerations in regard to the parturient with Zika viral illness and associated diseases.
Topics: Aedes; Anesthesia, Obstetrical; Animals; Blood-Borne Pathogens; Female; Guillain-Barre Syndrome; Humans; Incidence; Infectious Disease Transmission, Vertical; Pregnancy; United States; Zika Virus; Zika Virus Infection
PubMed: 27871511
DOI: 10.1016/j.jclinane.2016.07.034 -
Journal of Dentistry Jun 2023Peri-implantitis is associated with bacterial plaque biofilms and with patients who have a history of periodontitis. Smoking is a risk factor for periodontitis, but the... (Review)
Review
OBJECTIVES
Peri-implantitis is associated with bacterial plaque biofilms and with patients who have a history of periodontitis. Smoking is a risk factor for periodontitis, but the relationship between smoking and peri‑implantitis is unclear. The aim of this systematic review was to assess evidence ascertaining the relationship between smoking and peri‑implant microbiota.
DATA SOURCES
An electronic search was conducted in the MEDLINE/PubMed, Embase and Scopus® databases in duplicate up to January 2023 without language restrictions. Studies were considered eligible for inclusion if they involved evaluation of the peri‑implant microbiota of smokers and nonsmokers. Methodological quality was assessed with the adapted Newcastle-Ottawa scale.
STUDY SELECTION
Fourteen studies were identified for inclusion in the present study, and 85.7% of the studies were defined as medium to high methodological quality. Overall, the evidence presented in this review was limited to medium to high methodological quality. The data indicates that significantly higher frequencies of anaerobic pathogens are detectable in healthy peri‑implant tissues of smokers. A lower diversity of microbiota was observed in healthy peri‑implant sites of smokers. In the transition from clinically healthy to a diseased status, smoking shaped a reduced peri‑implant microbiota by depleting commensal and enriching pathogenic species.
CONCLUSIONS
The composition of peri‑implant microbiota may be influenced by smoking. More studies are needed to determine the impact of smoking on peri‑implant microbiota.
CLINICAL SIGNIFICANCE
In the transition from clinically healthy to a diseased status, smoking shaped a reduced peri‑implant microbiota by depleting commensal and enriching pathogenic species. The composition of peri‑implant microbiota may be influenced by smoking.
Topics: Humans; Peri-Implantitis; Smoking; Periodontitis; Risk Factors; Microbiota; Dental Implants
PubMed: 37088258
DOI: 10.1016/j.jdent.2023.104525 -
BMJ Open Mar 2016Observational studies have suggested that Escherichia coli sequence type (ST) 131 and Klebsiella pneumoniae ST258 have hyperendemic properties. This would be obvious... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Observational studies have suggested that Escherichia coli sequence type (ST) 131 and Klebsiella pneumoniae ST258 have hyperendemic properties. This would be obvious from continuously high incidence and/or prevalence of carriage or infection with these bacteria in specific patient populations. Hyperendemicity could result from increased transmissibility, longer duration of infectiousness, and/or higher pathogenic potential as compared with other lineages of the same species. The aim of our research is to quantitatively estimate these critical parameters for E. coli ST131 and K. pneumoniae ST258, in order to investigate whether E. coli ST131 and K. pneumoniae ST258 are truly hyperendemic clones.
PRIMARY OUTCOME MEASURES
A systematic literature search was performed to assess the evidence of transmissibility, duration of infectiousness, and pathogenicity for E. coli ST131 and K. pneumoniae ST258. Meta-regression was performed to quantify these characteristics.
RESULTS
The systematic literature search yielded 639 articles, of which 19 data sources provided information on transmissibility (E. coli ST131 n=9; K. pneumoniae ST258 n=10)), 2 on duration of infectiousness (E. coli ST131 n=2), and 324 on pathogenicity (E. coli ST131 n=285; K. pneumoniae ST258 n=39). Available data on duration of carriage and on transmissibility were insufficient for quantitative assessment. In multivariable meta-regression E. coli isolates causing infection were associated with ST131, compared to isolates only causing colonisation, suggesting that E. coli ST131 can be considered more pathogenic than non-ST131 isolates. Date of isolation, location and resistance mechanism also influenced the prevalence of ST131. E. coli ST131 was 3.2 (95% CI 2.0 to 5.0) times more pathogenic than non-ST131. For K. pneumoniae ST258 there were not enough data for meta-regression assessing the influence of colonisation versus infection on ST258 prevalence.
CONCLUSIONS
With the currently available data, it cannot be confirmed nor rejected, that E. coli ST131 or K. pneumoniae ST258 are hyperendemic clones.
Topics: Epidemics; Escherichia coli; Escherichia coli Infections; Humans; Klebsiella Infections; Klebsiella pneumoniae; Microbial Sensitivity Tests
PubMed: 26988349
DOI: 10.1136/bmjopen-2015-009971 -
PLoS Neglected Tropical Diseases Apr 2020Mycetoma is one of the badly neglected tropical diseases, characterised by subcutaneous painless swelling, multiple sinuses, and discharge containing aggregates of the...
Mycetoma is one of the badly neglected tropical diseases, characterised by subcutaneous painless swelling, multiple sinuses, and discharge containing aggregates of the infecting organism known as grains. Risk factors conferring susceptibility to mycetoma include environmental factors and pathogen factors such as virulence and the infecting dose, in addition to host factors such as immunological and genetic predisposition. Epidemiological evidence suggests that host genetic factors may regulate susceptibility to mycetoma and other fungal infections, but they are likely to be complex genetic traits in which multiple genes interact with each other and environmental factors, as well as the pathogen, to cause disease. This paper reviews what is known about genetic predisposition to fungal infections that might be relevant to mycetoma, as well as all studies carried out to explore host genetic susceptibility to mycetoma. Most studies were investigating polymorphisms in candidate genes related to the host immune response. A total of 13 genes had allelic variants found to be associated with mycetoma, and these genes lie in different pathways and systems such as innate and adaptive immune systems, sex hormone biosynthesis, and some genes coding for host enzymes. None of these studies have been replicated. Advances in genomic science and the supporting technology have paved the way for large-scale genome-wide association and next generation sequencing (NGS) studies, underpinning a new strategy to systematically interrogate the genome for variants associated with mycetoma. Dissecting the contribution of host genetic variation to susceptibility to mycetoma will enable the identification of pathways that are potential targets for new treatments for mycetoma and will also enhance the ability to stratify 'at-risk' individuals, allowing the possibility of developing preventive and personalised clinical care strategies in the future.
Topics: Female; Genetic Predisposition to Disease; Genome-Wide Association Study; Humans; Immunologic Factors; Male; Mycetoma; Polymorphism, Genetic; Risk Factors
PubMed: 32352976
DOI: 10.1371/journal.pntd.0008053 -
Journal of Veterinary Internal Medicine Sep 2019The pathogenic role of mycoplasmas in the lower respiratory tract (LRT) of dogs is debated, because mycoplasmas can be isolated from both healthy and sick dogs. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The pathogenic role of mycoplasmas in the lower respiratory tract (LRT) of dogs is debated, because mycoplasmas can be isolated from both healthy and sick dogs.
OBJECTIVES
To critically assess available data from controlled observational studies on the role of 4 mycoplasma species in LRT disease of dogs.
DESIGN
Systematic review and meta-analyses.
METHODS
Seven electronic databases were searched for relevant publications. Risk of bias was assessed by the Newcastle-Ottawa Scale. Meta-analyses, stratified by mycoplasmal species, were performed using a random effects Bayesian model with noninformative priors to estimate pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the association between Mycoplasma cynos, Mycoplasma canis, Mycoplasma spumans, and Mycoplasma edwardii and LRT disease in dogs.
RESULTS
Five studies were included from 1201 references identified. All studies dealt with M. cynos, whereas 3 dealt with the other mycoplasma species. A significant association was found between M. cynos and LRT disease (Bayesian OR, 3.60; CI, 1.31-10.29). Conversely, M. canis, M. spumans, and M. edwardii were not significantly associated with LRT signs (Bayesian OR, 1.06; CI, 0.10-14.63; Bayesian OR, 3.40; CI, 0.16-54.27; and Bayesian OR, 1.04; CI, 0.05-23.54, respectively).
CONCLUSIONS AND CLINICAL IMPORTANCE
Results support a pathogenic role of M. cynos and a commensal role of M. canis and M. edwardii in LRT in dogs. Although the association was not significant based on the CI, the point estimate of the Bayesian OR was relatively high for M. spumans, making its role less clear. Mycoplasma cynos-specific polymerase chain reaction should be considered on samples from dogs with LRT.
Topics: Animals; Dog Diseases; Dogs; Mycoplasma; Mycoplasma Infections; Respiratory Tract Infections
PubMed: 31297880
DOI: 10.1111/jvim.15568 -
Tuberculosis (Edinburgh, Scotland) May 2016Infection with HIV-1 greatly increases the risk of active tuberculosis (TB). Although hypotheses suggest HIV-1 disrupts Mycobacterium tuberculosis (Mtb) granuloma... (Meta-Analysis)
Meta-Analysis Review
Infection with HIV-1 greatly increases the risk of active tuberculosis (TB). Although hypotheses suggest HIV-1 disrupts Mycobacterium tuberculosis (Mtb) granuloma function, few studies have examined this directly. The objective of this study was to determine what evidence exists about the effect HIV-1 co-infection has upon Mtb granulomas. A systematic search of PubMed, Web of Science, and Medline up to 20 March 2015 was conducted, to identify studies comparing Mtb-infected tissue from HIV-1 infected and uninfected persons, or HIV-1 infected persons with stratified peripheral CD4 T cell (pCD4) counts. We summarized findings that focused on how HIV-1 changes granuloma formation, bacterial presence, cellular composition, and cytokine production. Nineteen studies with a combined sample size of 899 persons were included. Although studies frequently were limited by variable or inadequately described definitions of outcomes and analytical methods, HIV-1 was found to be associated with increased bacillary load within Mtb-infected tissue. Reductions in pCD4 counts within co-infected persons associated with both poorer granuloma formation and higher bacterial load. The high degree of heterogeneity among studies combined with experimental limitations made it difficult to conclusively support previously published and prevalent hypotheses about HIV-1/Mtb co-infection granulomas. To elucidate the validity of these hypotheses we have described areas that can be improved in future studies in order to clarify the influence HIV-1 co-infection has upon the Mtb granuloma.
Topics: Chi-Square Distribution; Coinfection; Cytokines; Granuloma; HIV Infections; HIV-1; Host-Pathogen Interactions; Humans; Mycobacterium tuberculosis; Odds Ratio; Prognosis; Risk Factors; Tuberculosis
PubMed: 27156620
DOI: 10.1016/j.tube.2016.02.010 -
Veterinary Research Oct 2023The global spread of avian influenza A viruses in domestic birds is causing increasing socioeconomic devastation. Various mechanistic models have been developed to... (Review)
Review
The global spread of avian influenza A viruses in domestic birds is causing increasing socioeconomic devastation. Various mechanistic models have been developed to better understand avian influenza transmission and evaluate the effectiveness of control measures in mitigating the socioeconomic losses caused by these viruses. However, the results of models of avian influenza transmission and control have not yet been subject to a comprehensive review. Such a review could help inform policy makers and guide future modeling work. To help fill this gap, we conducted a systematic review of the mechanistic models that have been applied to field outbreaks. Our three objectives were to: (1) describe the type of models and their epidemiological context, (2) list estimates of commonly used parameters of low pathogenicity and highly pathogenic avian influenza transmission, and (3) review the characteristics of avian influenza transmission and the efficacy of control strategies according to the mechanistic models. We reviewed a total of 46 articles. Of these, 26 articles estimated parameters by fitting the model to data, one evaluated the effectiveness of control strategies, and 19 did both. Values of the between-individual reproduction number ranged widely: from 2.18 to 86 for highly pathogenic avian influenza viruses, and from 4.7 to 45.9 for low pathogenicity avian influenza viruses, depending on epidemiological settings, virus subtypes and host species. Other parameters, such as the durations of the latent and infectious periods, were often taken from the literature, limiting the models' potential insights. Concerning control strategies, many models evaluated culling (n = 15), while vaccination received less attention (n = 6). According to the articles reviewed, optimal control strategies varied between virus subtypes and local conditions, and depended on the overall objective of the intervention. For instance, vaccination was optimal when the objective was to limit the overall number of culled flocks. In contrast, pre-emptive culling was preferred for reducing the size and duration of an epidemic. Early implementation consistently improved the overall efficacy of interventions, highlighting the need for effective surveillance and epidemic preparedness.
Topics: Animals; Influenza in Birds; Poultry; Disease Outbreaks; Influenza A virus; Animals, Domestic
PubMed: 37853425
DOI: 10.1186/s13567-023-01219-0