Antibiotic Resistance Profile and Distribution of Oxacillinase Genes Among Clinical Isolates of Acinetobacter baumannii in Shiraz Teaching Hospitals, 2012 - 2013

Abstract

Background:The emergence of multidrug-resistant Acinetobacter baumannii complicates the therapy of the related infections. Hospital isolates of A. baumannii are usually multidrug-resistant. The problem is compounded by increasing resistance to broad-spectrum antibiotics including carbapenems.Objectives:The aim of this study was to determine antimicrobial susceptibility patterns and distribution of blaOXA-type carbapenemases genes among A. baumannii isolates from hospitalized patients in Shiraz, Southwest Iran.Materials and Methods:Two hundred A. baumannii isolates were recovered from different clinical specimens in four Shiraz teaching hospitals. Isolates were detected as A. baumannii by Microgen kit and PCR with specific primers of blaOXA-51-like gene. Antimicrobial susceptibility testing was determined by disk diffusion method for all the isolates. Multiplex PCR assays were performed for detection of blaOXA-23-like, blaOXA-24-like and blaOXA-58-like genes.Results:All the isolates were susceptible to colistin and polymyxin B. Moreover, all of them were resistant to piperacillin, piperacillin-tazobactam, ampicillin, ceftazidime, cefoxitin and aztreonam. Eighty (40%) isolates had positive results for blaOXA-23-like, 14 (7%) for blaOXA-24-like and 1 (0.5%) isolate for blaOXA-58-like. The co-existence of studied genes was detected for blaOXA-23-like plus blaOXA-24-like in nine (4.5%) isolates.Conclusions:The prevalence of carbapenem resistant A. baumannii isolates in Shiraz hospitals is high. The blaOXA-23-like gene was the most frequent carbapenemase identified among resistant A. baumannii isolated in Shiraz hospitals. The increasing incidence of A. baumannii is a serious concern, therefore control of this pathogen and taking preventive measures are emphasized.

Comparative in vitro activity of carbapenems against clinical isolates of Acinetobacter baumannii

“…; Kooti et al . ). Prior to the current investigation, there was only one study in Iran, which assessed the susceptibility of 76 isolates of Ac.…”

Evaluating the resistance pattern of gram-negative bacteria during three years at the nephrology ward of a referral hospital in southwest of Iran

“…has been increased. It has been ranged from only 14.6% in 2004-2005 to 50.9%, 52.5%, 62%, 67.5%, 91.5%, and 99% in years between 2008 and 2013 at Tehran hospitals ( 33 ). This rate reported from other regions of Iran has been 60.8% in Bandar Abbas at 2006 ( 12 ), 96.1% in Ahvaz at 2013 ( 34 ), and 75%-79.8% in Kermanshah at 2013 ( 35 ).…”

Antibiogram and beta-lactamase genes among cefotaxime resistant E. coli from wastewater treatment plant

“…Several antibiotic resistance determinants were detected in this study. These include bla TEM , bla CTX-M , bla SHV , bla VIM , bla OXA-1 , bla KPC-2 and bla NDM-1 , which might be responsible for some detected resistance to the cefotaxime and other beta-lactam antibiotics [67]. Though bla VIM was not detected, bla OXA-1 , bla KPC-2 and bla NDM-1 might be responsible for intermediate resistance to meropenem by the cefotaxime-resistant E. coli [67,68].…”

“…These include bla TEM , bla CTX-M , bla SHV , bla VIM , bla OXA-1 , bla KPC-2 and bla NDM-1 , which might be responsible for some detected resistance to the cefotaxime and other beta-lactam antibiotics [67]. Though bla VIM was not detected, bla OXA-1 , bla KPC-2 and bla NDM-1 might be responsible for intermediate resistance to meropenem by the cefotaxime-resistant E. coli [67,68]. Several beta-lactamase genes like bla CTX-M , bla SHV and bla TEM have also been reported in both hospital and municipal wastewater effluents [18,69].…”