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Phenotypic and Molecular Characterization of β-Lactamases among Enterobacterial Uropathogens in Southeastern Nigeria
Little is known about the molecular basis of antibiotic resistance among uropathogens in Southeast Nigeria. The aim of the study was to characterize enterobacterial uropathogens with respect to drug resistance. One hundred (100) enterobacterial uropathogens were studied. Their antibiotic susceptibility patterns were evaluated using disk diffusion, screened, and confirmed phenotypically for the presence of β-lactamases: ESBL, AmpC, carbapenemase, and MBLs. Screen positives were further tested for various β-lactamase genes by PCR. Our isolates showed variable resistance to most drugs tested. Out of the 58 ESBL screen positive E. coli, 35 were confirmed positive with PCR. The predominant ESBL gene was blaTEM while blaSPM was the most prevalent among MBL genes. Forty-six percentage of the screen positive Salmonella isolates coharbored blaTEM + SHV genes. Nine of the 10 ESBL screen positive K. pneumoniae were phenotypically and PCR positive. Three isolates of K. pneumoniae were positive for MBL genes. All the 10 C. freundii were positive for ESBL genes. The study showed high prevalence of drug-resistant genes among the enterobacterial uropathogens. Majority of the uropathogens harbored >1 antibiotic-resistant gene, and the most predominant gene was ESBL (blaTEM) followed by the MBL (SPM) gene.
Characterization of Integrons and Antimicrobial Resistance in Escherichia coli Sequence Type 131 Isolates
Background. Escherichia coli sequence type 131 (ST131) is an important multidrug-resistant extraintestinal pathogen, which can cause many kinds of infections. Integrons may play a crucial role in the dissemination of antibiotic resistance genes. The purpose of this study was to characterize the prevelance of integrons among E. coli ST131 strains in China. Methods. Eighty-three E. coli ST131 isolates were used in this study. The antibiotic susceptibility test was performed by the disk diffusion method. The presence and characterization of class 1, 2, and 3 integrons, as well as promotor of gene cassettes and other antimicrobial resistance genes, were detected by PCR and DNA sequencing. Transfer of integrons was carried out using a broth culture mating method. Clonal relatedness of E. coli ST131 isolates was analyzed by PFGE. Results. Overall, 26.5% (22/83) of the E. coli ST131 isolates carried class 1 integrons. Class 2 and 3 integrons were not found in this study. Two types of gene cassette arrays were demonstrated in this study and were as follows: dfrA17-aadA5 and aac(6′)-Ib-cr-cmlA5. Only one type of Pc promoter variant was detected among 22 integron-positive isolates (PcW). In vivo transfer of integron was successful for 9 of integron-positive E. coli ST131 isolates harboring resistance gene cassettes. Results of PFGE demonstrated that the integron-positive E. coli ST131 isolates were grouped into 12 different PFGE clusters. Conclusions. Our study showed a low prevalence of integrons was detected in E. coli ST131. Continued surveillance of this mobile genetic element should be performed to study the evolution of antibiotic resistance among E. coli ST131.
Pneumocystis jirovecii Pneumonia in Patients with Nephrotic Syndrome: Application of Lymphocyte Subset Analysis in Predicting Clinical Outcomes
Purpose. With immunosuppressants being widely used, Pneumocystis jirovecii pneumonia (PCP) has been increasing and could be life-threatening among HIV-negative patients. This study aimed at identifying prognostic factors of PCP in patients with nephrotic syndrome. Methods. We retrospectively investigated patients with nephrotic syndrome who were diagnosed with PCP. The diagnosis of PCP was based on clinical manifestations, radiological findings, and microbiological confirmatory tests. Predictors of outcome were determined with multivariate logistic regression analysis. Results. A total of 57 patients were included in this study. The PCP mortality was 33.3%, which increased to 48.6% if ICU admission was required and to 60% when mechanical ventilation was needed. The T lymphocyte count and CD4/CD8 ratio independently predicted the outcome of PCP, so did the CD4+ T lymphocyte count (OR, 0.981; 95% CI, 0.967–0.996; ). The cut-off value of 71 cells/μl for the CD4+ T lymphocyte count was determined to identify patients with poor prognosis. No association was found between PCP mortality and the type of immunosuppressant used. Conclusions. PCP is a fatal complication among nephrotic syndrome patients receiving immunosuppressive therapy. The CD4+ T lymphocyte count is suggested as an independent predictor of prognosis, which can be used clinically to identify patients with high risk of unfavorable outcomes.
Gut Microbiota Alterations from Three-Strain Yogurt Formulation Treatments in Slow-Transit Constipation
The objective of this study was to evaluate the effects of a three-strain yogurt formulation in slow-transit constipation (STC) patients. Each individual in both treatment groups consumed 250 mL of the formulated yogurt daily for a week (7 days), and fecal samples were collected for gut microbiota and short-chain fatty acid (SCFA) analyses. A significant increase in the defection frequency () and bacterial diversity () at the 100% sequence homology level and a decrease in the concentrations of acetic acid (), propionic acid (), and butanoic acid () were observed after the STC patients consumed three-strain yogurt formulation. In addition, the consumption of the three-strain yogurt formulation significantly altered the composition of the intestinal bacteria in the STC patients. The relative abundances of 23 genera in the top dominating genera were altered significantly after the STC patients consumed the yogurt. In summary, the consumption of 250 mL day− the three-strain yogurt formulation described in this study can play a role in improving the symptoms of STC.
Carriage of Extended-Spectrum-β-Lactamase- and AmpC-β-Lactamase-Producing Enterobacteriaceae (ESBL-PE) in Healthy Community and Outpatient Department (OPD) Patients in Nepal
Background. Extended-spectrum β-lactamase (ESBL)- and AmpC-β-lactamase-producing Enterobacteriaceae have recently emerged as a public threat in the treatment of nosocomial as well as community-acquired infections. Very little information is currently available about its existence in Nepal. We, therefore, aim to determine the prevalence of ESBL and AmpC-β-lactamase-producing Enterobacteriaceae and also to determine their drug resistance pattern. Methods. During a 6-month period (November 2014–April 2015), a total of 190 stool specimens from 190 participants were obtained from different population. Of the total 260 fecal isolates, 152 from outpatient department (OPD) and 108 from healthy volunteer were collected. Stool specimens were cultured and enterobacterial isolates were subjected to antimicrobial susceptibility tests according to the standard microbiologic guidelines. ESBL was screened using ceftazidime (CAZ, 30 μg) and cefotaxime (CTX, 30 μg) disks and confirmed by double-disk synergy test. AmpC-β-lactamase enzyme production was detected by the aminophenylboronic acid inhibitor-based detection method. Antibiotic susceptibility test was performed for ESBL-positive isolates as per the Kirby-Bauer disk diffusion method, and interpretation was done according to CLSI (Clinical and Laboratory Standard Institute). Results. The prevalence of ESBL, AmpC-β-lactamases, and coproducer (ESBL + AmpC-β-lactamase) producing Enterobacteriaceae in OPD participants were 30.92%, 18.4%, and 13.81%, respectively, while 25%, 6.4%, and 1.8% in healthy population. ESBL-producing E. coli was 70.2% followed by K. pneumoniae (12.7%), and among AmpC-β-lactamase producer, E. coli were detected in half of the isolates (14/28, 50.0%) among OPD patients. Similarly, E. coli remained the most frequent ESBL producers 21/27 (77.8%) followed by K. pneumoniae 4/27 (14.21%) in healthy participants, and K. pneumoniae 5/7 (71.42%) and C. freundii 2/7 (28.57%) were detected highest among AmpC-β-lactamase-producing isolates. All isolates were highly sensitive (100%) to imipenem in both OPD and healthy participants. Conclusion. Our study revealed a high prevalence of ESBL- and AmpC-β-lactamase-producing enteric pathogen in Nepalese OPD and healthy population. The significant increase of these isolates and increased rate of drug resistance indicates a serious threat that stress the need to implement the surveillance system and a proper control measure so as to limit the spread of ESBL-producing Enterobacteriaceae (ESBL-PE) in both OPD as well as in community. Therefore, healthcare providers need to be aware that ESBL- and AmpC-β-lactamase-producing strains are not only circulating in hospital environments but also in the community and should be dealt with accordingly.
Measles Virus Imported by International Traveler in Jiangsu Province of China, in 2018 and 2019
Measles remains a public health concern in many regions, and the imported measles cases continue to challenge the measles elimination program for most of the countries where measles was verified to be eliminated or approaching elimination. The imported measles cases have been reported since October, 2017, in Jiangsu province, China. In this study, we reported the first imported B3 genotype measles virus from Egypt and the second imported D8 genotype measles virus from Philippines through international traveling. No secondary measles cases were found after these imported cases. Our findings highlighted the importance of measles vaccination targeting international travelers in China.