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Anaerobe Apr 2020Clostridioides difficile typing is invaluable for the investigation of both institution-specific outbreaks as well as national surveillance. While the epidemic ribotype...
Clostridioides difficile typing is invaluable for the investigation of both institution-specific outbreaks as well as national surveillance. While the epidemic ribotype 027 (RT027) has received a significant amount of resources and attention, ribotype 106 (RT106) has become more prevalent throughout the past decade. The purpose of this systematic review was to comprehensively summarize the genetic determinants, antimicrobial susceptibility, epidemiology, and clinical outcomes of infection caused by RT106. A total of 68 articles published between 1999 and 2019 were identified as relevant to this review. Although initially identified in the United Kingdom in 1999, RT106 is now found worldwide and became the most prevalent strain in the United States in 2016. Current data indicate that RT106 harbors the tcdA and tcdB genes, lacks binary toxin genes, and does not contain any deletions in the tcdC gene, which differentiates it from other epidemic strains, including ribotypes 027 and 078. Interestingly, RT106 produces more spores than other strains, including RT027. Overall, RT106 is highly resistant to erythromycin, clindamycin, fluoroquinolones, and third-generation cephalosporins. However, the MIC in most studies are one to two fold dilutions below the epidemiologic cut-off values of metronidazole and vancomycin, suggesting both are acceptable treatment options from an in vitro perspective. The few clinical outcomes studies available concluded that RT106 causes less severe disease than RT027, but patients were significantly more likely to experience multiple CDI relapses when infected with a RT106 strain. Specific areas warranting future study include potential survival advantages provided by genetic elements as well as a more robust investigation of clinical outcomes associated with RT106.
Topics: Anti-Bacterial Agents; Clostridioides difficile; Clostridium Infections; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Public Health Surveillance; Ribotyping; Spores, Bacterial; Virulence
PubMed: 32007682
DOI: 10.1016/j.anaerobe.2019.102142 -
The Journal of Infectious Diseases Jul 2007Reinfection is a major contributor to tuberculosis (TB). It seems that the higher the local incidence, the higher the proportion of reinfection. (Review)
Review
BACKGROUND
Reinfection is a major contributor to tuberculosis (TB). It seems that the higher the local incidence, the higher the proportion of reinfection.
METHODS
Based on a systematic review of the literature, we established a regression model to predict the reinfection proportion from the local incidence. We then used our local data to verify the algorithm.
RESULTS
Of the 23 studies addressing reinfection in recurrent TB, 6 were population based. The reinfection proportion was correlated with the local incidence (reinfection proportion=-29.7+36.8 x log Incidence) (95% confidence interval [CI] for coefficient, 15.3-58.3; R2=0.849). The reinfection proportion in Taiwan (incidence, 62.4/100,000 people) was estimated to be 36% (95% CI, 3%-69%). Of our 49 recurrent patients, 51% had reinfection. Patients with reactivation seemed more likely to have underlying diseases and less likely to be smear positive. The relapse isolates seemed more resistant than the initial isolates.
CONCLUSIONS
The regression model could possibly predict the TB reinfection proportion from the local incidence. This algorithm is probably helpful in policy making for TB control programs. In areas where TB is endemic, reinfection might be responsible for >50% of TB cases, and aggressive surveillance to detect asymptomatic carriers could be an important strategy for controlling the disease.
Topics: DNA Fingerprinting; Forecasting; Humans; Incidence; Models, Statistical; Recurrence; Regression Analysis; Tuberculosis
PubMed: 17570116
DOI: 10.1086/518898 -
Anaerobe Aug 2019Clostridioides difficile is considered one of the main etiological agents of bacterial diarrhea associated with the use of antibiotics. It is an important nosocomial...
Clostridioides difficile is considered one of the main etiological agents of bacterial diarrhea associated with the use of antibiotics. It is an important nosocomial pathogen and the main cause of morbidity and mortality. In recent years, infections associated with C. difficile have led to numerous investigations. It is well known that C. difficile associated diarrhea (CDAD) is favored by the suppression or imbalance of the intestinal microbiome during or after antibiotic therapy. Other risk factors are, for instance, advanced age, long periods of hospitalization, chemotherapy, and other gastrointestinal infections. In the 2000's, the number of CDAD cases largely increased due to the emergence of the epidemic clone named BI/NAP1 ribotype 027, responsible for causing several outbreaks in developed countries, such as Canada, the United States, and the United Kingdom. The presence of the epidemic clone has been reported in Asia, Latin America and Australia, however, infections associated with C. difficile (CDI) in these geographic regions are usually caused by other ribotypes. In Brazil, for instance, epidemiological data on the incidence of CDI are still limited, especially regarding the spread of C. difficile within hospital units, the spectrum of toxigenic genes and the antimicrobial resistance profile. Some studies have demonstrated the importance of notifying cases related to CDI and taking special care measures in order to minimize the spread of epidemic strains in Brazil. Finally, epidemiological analysis of the prevalent and/or exclusive ribotypes circulating in Brazil can contribute to understand and to correlate characteristics associated with the biology of this pathogen with other globally circulating ribotypes. This review aimed to summarize all published work related to the isolation of C. difficile from human patients in Brazil, being the main focus, the methodologies used for identification of prevalent ribotypes, the antimicrobial susceptibility profile, and the diseases associated with the acquisition of CDI.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents; Brazil; Child; Child, Preschool; Clostridioides difficile; Clostridium Infections; Diarrhea; Female; Hospitalization; Humans; Incidence; Infant; Male; Middle Aged; Ribotyping; Risk Factors; Young Adult
PubMed: 30851427
DOI: 10.1016/j.anaerobe.2019.03.002