British Microbiology Research Journal, ISSN: 2231-0886,Vol.: 4, Issue.: 12 (December)

Original-research-article

Prevalence and Genotypic Characterization of Extended- Spectrum Beta-Lactamases Produced by Gram Negative Bacilli at a Tertiary Care Hospital in Rural South Western Uganda

 

Acaku Moses¹, Freddie Bwanga^2,3, Yap Boum⁴ and Joel Bazira^1*

¹Department of Microbiology, Mbarara University of Science and Technology, Mbarara, Uganda.
²Department of Medical Microbiology, Makerere University College of Health sciences
³MBN Clinical Laboratories Kampala, Uganda.
⁴Epicenter Mbarara Research Base, Mbarara, Uganda.

Article Information

Editor(s):

(1) Dr. Frank Lafont, Center of Infection and Immunity of Lille, Pasteur Institute of Lille, France.

Reviewers:

(1) Eucharia Nmema, Ondo State University of Science and Technology, Nigeria.

(2) Anonymous

(3) Anonymous

(4) Anonymous

Complete Peer review History: http://www.sciencedomain.org/review-history/5867

Aim: To determine the prevalence and genotypic characterisation of extended spectrum beta-lactamases produced by gram negative bacilli isolated at Mbarara Regional Referral Hospital (MRRH).
Samples: Gram negative clinical isolates.
Study Design: Laboratory-based descriptive cross-sectional study.
Place and Duration of the Study: MRRH, June and August 2012.
Methods: Gram negative clinical isolates were sub cultured, and identified using biochemical tests. They were screened for ESBL by using oxyimino-cephalosporins and confirmed by double disc synergy Genotyping was performed using the PCR for TEM, SHV and CTX-M. Susceptibility pattern for the extended spectrum beta-lactamases, (ESBL) - positive isolates to other antibiotic classes was performed by the Kirby Bauer Technique.
Results: A total of 484 isolates were included in the study. The commonest ESBL producers were Escherichia coli (34%), followed by unidentified coliforms (19.3%) and Klebsiella spp. (12.7%). Phenotypically, 88/484 were ESBL producers while genotypically 213/ 484 possessed ESBL genes. The ESBL genes were bla_CTX-M (146; 70%), bla_SHV (72; 34%) and bla_TEM (100; 47%). 87of 213 isolates expressed more than one ESBL gene. Of these 36 (7.4%) produced bla_CTX-M/bla_SHV, 28 (5.8%) bla_CTX-M /bla_TEM, 4 (0.8%) bla_SHV/ bla_TEM and 19 (3.9%) bla_CTX-M/bla_SHV/bla_TEM. Sixty two (16%) were phenotypically and genotypically positive, 12 (3%) of the isolates were phenotypically positive but genotypically negative and 140 (37%) isolates were phenotypically negative but genotypically positive. The ESBL producers were highly susceptible to imipenem (95%), nitrofurantoin (66%) but less susceptible to ampicillin (4%) and ticarcillin (7%).
Conclusion: ESBL production among the Gram-negative clinical isolates at MRRH is very high with several isolates possessing multiple genes. The ESBL producers are highly susceptible to imipenem, but very resistant to ciprofloxacin.

Keywords :

Antibiotics; resistance patterns; sensitivity patterns; ESBL; Uganda.

Full Article - PDF    Page 1541-1550

DOI : 10.9734/BMRJ/2014/9792

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