Plasmid-Mediated AmpC: Prevalence in Community-Acquired Isolates in Amsterdam, the Netherlands, and Risk Factors for Carriage
PLOS ONE
Authors: Reuland, E. Ascelijn; Halaby, Teysir; Hays, John P.; de Jongh, Denise M. C.; Snetselaar, Henrieke D. R.; van Keulen, Marte; Elders, Petra J. M.; Savelkoul, Paul H. M.; Vandenbroucke-Grauls, Christina M. J. E.; al Naiemi, Nashwan
Abstract
Objectives The objective of this study was to determine the prevalence of pAmpC beta-lactamases in community-acquired Gram negative bacteria in the Netherlands, and to identify possible risk factors for carriage of these strains. Methods Fecal samples were obtained from community-dwelling volunteers. Participants also returned a questionnaire for analysis of risk factors. Screening for pAmpC was performed with selective enrichment broth and a selective screening agar. Confirmation of AmpC-production was performed with two double disc combination tests: cefotaxime and ceftazidime with either boronic acid or cloxacillin as inhibitor. Multiplex PCR was used as gold standard for detection of pAmpC. 16S rRNA PCR and AFLP were performed as required, plasmids were identified by PCR-based replicon typing. Questionnaire results were analyzed with SPSS, version 20.0. Results Fecal samples were obtained from 550 volunteers; mean age 51 years (range: 18-91), 61% were females. pAmpC was present in seven E. coli isolates (7/550, 1.3%, 0.6-2.7 95% CI): six CMY-2-like pAmpC and one DHA. ESBL-encoding genes were found in 52/550 (9.5%, 7.3-12.2 95% CI) isolates; these were predominantly blaCTX-M genes. Two isolates had both ESBL and pAmpC. Admission to a hospital in the previous year was the only risk factor we identified. Conclusions Our data indicate that the prevalence of pAmpC in the community seems still low. However, since pAmpC-producing isolates were not identified as ESBL producers by routine algorithms, there is consistent risk that further increase of their prevalence might go undetected.
The Prevalence of Antibiotic and Toothpaste Sensitivity found in Oral Streptococcal Isolates in Healthy Individuals in the Okada Community of Nigeria
MAKARA JOURNAL OF HEALTH RESEARCH
Authors: Okwu, Maureen U.; Mitsan, Olley
Abstract
Background: This study aimed to determine the prevalence, antibiotic, and toothpaste sensitivity of oral streptococcal isolates in healthy individuals in the Okada community of Nigeria. Methods: Oral samples were collected from 230 volunteers and were subjected to standard microbiological tests. Antibacterial sensitivity tests were carried out on the streptococcal isolates that were obtained using a disk diffusion technique, and eight kinds of toothpaste (A-H) were screened for their antibacterial effects on Streptococcus mutans (S. mutans). Results: The prevalence of oral streptococci found in this study was 26.1% and the predominant species was S. salivarius (13.9%). S. salivarius was highly resistant to cloxacillin (100%) and Augmentin (96.9%), whilst resistance to gentamicin and erythromycin was low at 21.9% and 3.1% respectively. S. mutans were completely sensitive to gentamicin whilst resistance to erythromycin was 33.3%. The entire Streptococcus species showed the lowest resistance to erythromycin (20.0%), followed by gentamicin (31.7%). At 100 mg/mL all toothpaste samples had antibacterial effects on S. mutans. At 50 mg/mL all samples except toothpastes G and H inhibited the bacterium. Toothpastes A and E had the lowest minimum inhibitory concentration of 25 mg/mL. Conclusions: Toothpastes A and E were the most effective toothpastes of the eight assessed in this study.