Frequency of metallo-β-lactamase and antimicrobial resistance patterns of Acinetobacter baumannii in carbapenem-resistant isolates in intensive care units

Abstract

Background: Acinetobacter baumannii, is a gram negative, non-fermenting cocobacill or cocci, which is mostly found in soil, different water sources, and many healthcare environments. A.baumannii is intrinsically resistance to many antibiotics. Nowadays carbapenem as MDR Acinetobacter baumannii is the last drug therapy to be used for the treatment of infection. Carbapenem resistance in Acinetobacter baumannii strains are also expanding and in turn the Acinetobacter baumannii drug resistance among strains is setting grounds for a crisis. The aim of this article is to study the frequency of metallo-β-lactamase and Antimicrobial Resistance patterns of Acinetobacter baumannii in Carbapenem-resistant Isolates in Intensive Care Units. Methods: In a cross sectional study during one year period (2012-2013), Acinetobacter baumannii isolates from clinical specimens of patients hospitalized in the intensive care unit (ICU) were identified by genetic and biochemical methods. The Susceptibility of isolates was determined by standard disk diffusion method according to CLSI. MBL-producing isolates were DDST method. Findings: 100 isolates were determined as Acinetobacter baumannii by phenotypic and molecular testing of clinical specimens were obtained. The antimicrobial patterns of isolates showed that 62 of isolates were resistant to amikacin, 88 to tetracycline, 92 to ceftazidime, 96 to imipenem and meropenem, 93 to ampicillin-sulbactam and 98 to ciprofloxacin trimethoprim-sulfamethoxazole and cefepime. By examining DDST, Acinetobacter baumannii strains which were non-susceptible to imipenem of 96 (95 strains), 9/97 were found to produce MBL. Conclusion: In order to prevent the spread of nosocomial infections caused by Acinetobacter baumannii in ICU, rapid and accurate report of MBL enzymes seems necessary in order to monitor better and more accurate tracking of multiple resistance Acinetobacter baumannii in hospital laboratories. � 2015, Isfahan University of Medical Sciences(IUMS). All Rights Reserved.