ABSTRACT
Objective: To determine, the susceptibility pattern of carbapenamase producing enterobacteriaceae [CPE] against polymyxinB, tigecycline and fosfomycin
Study Design: Descriptive cross sectional
Place and Duration of Study: The study was carried out in the Department of Microbiology PNS Shifa Karachi, from 26 Sep 2013 to 25 Mar 2014
Material and Methods: All specimens were inoculated on blood and macConkey agar, incubated aerobically at 35degreeC - 37degreeC for 18 to 24 hours. After identification of gram negative rods by colony morphology, Gram's staining and biochemical reactions, these were screened for Carbapenems resistance with imipenem and meropenem 10 microg discs along with routine first and second line antibiotics by Kirby-Bauer disc diffusion technique according to Clinical Laboratory Standard Institute [CLSI] guide lines. All isolated CPE were saved and then inoculated on Mueller-Hinton agar [MHA]. Antimicrobial susceptibility against polymyxin B, Tigecycline and Fosfomycin was done by Kirby-Bauer disc diffusion method using disc polymyxin B 300 units, Tigecycline 15microg and Fosfomycin 200microg. Zone diameters greater than 24 mm were taken as sensitive for Tigecycline 15microg, 16mm for Fosfomycin 200 microg and 12 mm for polymyxin B 300 units
Results: Clinical specimens of 171 patients who fulfilled the inclusion criteria were included in our study. Mean +/- SD of age was 42.02 +/- 22.367 with C.I [38.65 - 45.40]. Out of 171 patients 110 [64%] were male and 61 [36%] were female. In vitro susceptibility results revealed that all the 171 [100%] CPE isolates susceptible to PolymyxinB, while susceptibility against Fosfomycin and Tigecycline was 132 [77%] and 49 [29%] respectively
Conclusion: CPE were found to be 100% susceptible to polymyxinB, while for Fosfomycin and Tigecycline susceptibility was 77% and 29% respectively
ABSTRACT
Objective:To know frequency of carbapenem resistance in Acinetobacter baumannii and its antimicrobial susceptibility pattern at PNS Shifa Hospital Karachi
Methodology:This study was carried out at PNS Shifa Hospital, Karachi, from 1st January 2015 till 31st October 2016. Samples from patients having different sites of infection were received in the laboratory from different wards of hospital and inoculated on culture plates. After 24 hours incubation, identification of non-lactose fermenter colonies of Acinetobacter baumannii was done by conventional methods. Antimicrobial susceptibility was recorded for Beta-lactam group of antimicrobials, Beta-lactam/Beta-lactamase inhibitor combination group, tetracyclines, fluoroquinolones and aminoglycosides as per CLSI guidelines
Results: During the study period, a total of 117 Acinetobacter baumannii isolates were identified from culture of different samples representing 5.0% of all bacterial isolates [n=2352] and 7.5% of all Gram-negative bacilli [n=1559] throughout the hospital. Out of one hundred and seventeen isolates, 52.1% [n=62] were found carbapenem resistant.Higher percentages of Acinetobacter baumannii were isolated among samples received from medical wards [26.4%].Percentage of Acinetobacter baumannii isolated was highest from the blood culture specimens [22.2%]. Isolates showed higher resistance against ceftriaxone [84.6%] followed by cotrimoxazole [65.8%] and ciprofloxacin [63.2%].Comparatively low resistance against doxycycline and minocycline [23.9%], and tigecycline [38.9%] was observed.Resistance pattern to other antimicrobials was gentamycin [54.7%], amikacin [55.6%], piperacillin-tazobactam [48.7%], cefoperazone-sulbactam [51.35%], meropenem [52.1%] and imipenem [52.1%]
Conclusion: Carbapenem resistance in Acinetobacter baumannii is increasing and therapeutic options left to treat are highly toxic especially for patients with co-morbidities