Occurrence of ESBL and MBL in Clinical Isolates of Pseudomonas aeruginosa From Lagos, Nigeria Occurrence of ESBL and MBL in Clinical Isolates of Pseudomonas aeruginosa From Lagos, Nigeria

Background: Widespread use and misuse of anti-infective agents have resulted in problems of drug resistance linked to treatment of infectious diseases caused by worrisome pathogens such as Pseudomonas aeruginosa. Infections caused by Pseudomonas aeruginosa with resistance to extended spectrum β-lactams and the carbapenems is emerging and requires the identification of effective alternative antimicrobial therapy and improved surveillance of the emergence of such resistance. A total of nonduplicate 97 strains of P. aeruginosa recovered from various clinical specimens and collected between March and August, 2006 were analysed for their resistance pattern. Methods: Antimicrobial susceptibility, Extended-Spectrum β-Lactamase (ESBL)and Metalloβ-Lactamase-Production (MBL) were determined using disk diffusion method, double disk synergy test and combined disk test respectively. Results: The Carbapenems had the highest activity against the strains tested (95.9%). This was followed by ceftazidime (79.4%). Amongst the 20 ceftazidime-resistant strains, 9 were found to be ESBL-producers. While the 4 strains resistant to the carbapenems were detected to be MBL-producers and were observed to be multiresistant. Amikacin was the most potent amongst the aminoglycosides (78.4%) while there was high resistance to the quinolones. Discussion: This study highlights needs to establish antimicrobial resistance surveillance networks for P. aeruginosa to determine the appropriate empirical treatment regimen. Bacterial strains resistant to most classes of antibiotics will continue to emerge unless inappropriate uses of drugs are curtailed and continuous education of infection control practices maintained. [The Journal Of American Science. 2007;3(4):81-85]. (ISSN: 1545-1003).