Prevalence of plasmid-mediated AmpC beta-lactamases in Enterobacteria isolated from urban and rural folks in Uganda

Abstract

Background: AmpC beta-lactamases are associated with increased resistance to third-generation cephalosporins. Here, we describe plasmid-mediated AmpC beta-lactamase-producing enterobacteria isolated from urban and rural dwellers in Uganda. Methods: Stool and urine from 1,448 individuals attending outpatient clinics in Kampala and two rural districts in central Uganda (Kayunga and Mpigi) were processed for isolation of Escherichia coli and Klebsiella. Following antibiotic susceptibility testing, cefoxitin resistant isolates, and amoxicillin/clavulanate resistant but cefoxitin susceptible isolates, were tested for AmpC beta-lactamase production using the cefoxitin-cloxacillin double-disc synergy test. Carriage of plasmid-mediated AmpC beta-lactamase-encoding genes (pAmpC) and extended spectrum beta-lactamase (ESBL) encoding genes was determined by PCR. Results: Nine hundred and thirty E. coli and 55 Klebsiella were recovered from the cultured samples, yielding 985 isolates (one per participant) investigated. One hundred and twenty nine isolates (13.1%, 129/985) were AmpC beta-lactamase producers, of which 111 were molecularly characterized for pAmpC/ESBL gene carriage. pAmpC genes were detected in 60% (67/111) of the AmpC beta-lactamase producers; pAmpC genes were also detected in 18 AmpC beta-lactamase non-producers and in 13 isolates with reduced susceptibility to third-generation cephalosporins, yielding a total of 98 isolates that carried pAmpC genes. Overall, the prevalence of pAmpC genes in cefoxitin resistant and/or amoxicillin/clavulanate resistant E. coli and Klebsiella was 59% (93/157) and 26.1% (5/23), respectively. The overall prevalence of pAmpC-positive enterobacteria was 10% (98/985); 16.4% (45/274) in Kampala, 6.2% (25/406) Kayunga, and 9.2% (28/305) Mpigi. Ciprofloxacin use was associated with carriage of pAmpC-positive bacteria, while residing in rural districts was associated with protection from carriage of pAmpC-positive bacteria. Conclusion: pAmpC beta-lactamase producing enterobacteria are prevalent in urban and rural dwellers in Uganda, therefore, cefoxitn should be included during routine susceptibility testing in this setting.

Antimicrobial Resistance Patterns and Molecular Characterization of <i>Klebsiella pneumoniae</i> in Clinical Isolates at Mbarara Regional Referral Hospital

“…A number of studies have shown different prevalence of K. pneumoniae among isolates determined in different study places putting it at around 3% to 12%; 3% [40], 5% [41]. The prevalence rate of Klebsiella pneumoniae was at 12.57% in this study which is in the agreement with the previous study done at MRRH…”

“…Prevalence was higher in Females (63.43%) than in the Male (36.57%) due to mechanical, hormonal and physiological changes at adolescence, during pregnancy and pre/post menopause. Females who were 50 years of age and above were found to be more infected with Klebsiella spp associated infection probably due to reduced immunity and pre/post menopause whereas Males between 18 and 50 years of age had the highest incidence of infection on age group greater than 50 years due to poor health living styles like increased sexual activities and living a dangerous life which is much supported by a number studies done around [40] [46].…”