Detection of drug resistance pattern among Gram-negative isolates

Both Gram-positive and Gram-negative bacteria are one of the main causes of infections in humans. Now a day, antimicrobial resistance (AMR) is considered as main public health threat, also AMR bacteria in different hospital wards are increasing significantly. Increasing number of extended spectrum beta-lactamase (ESBL) producers has reduced the treatment options which resulted in emergence of multidrug resistant strains, treatment failure and hence increased mortality. To know the drug resistance pattern among gram negative isolates and detection of ESBL production. A retrospective study of all gram negative isolates was conducted. Total of 177 isolates were isolated from various clinical samples. They were processed and identified by standard Microbiological procedures. The antibiotics susceptibility testing was performed by Kirby- Bauer disc diffusion method using CLSI guidelines. ESBL was detected by combined disc test using ceftazidime (30μg) alone and in combination with clavulanic acid disc. Of 285 samples processed, 177 Gram-negative isolates were isolated which includes E. coli, Klebsiella spp., Pseudomonas aeruginosa, Proteus spp., Citrobacter spp., Enterobacter spp., and Acinetobacter spp. Males 104 (58.8%) were commonly involved as compared to females 73 (41.2%).Of 177 isolates tested,90(50.8%) are from urine sample, 83(46.9%) from pus sample and 4(2.3%) from blood sample. ESBL was detected in 92 (52%) isolates. They showed least resistance to amikacin 36 (20.3%), piperacillin-tazobactam 30 (16.9%) and meropenem 10 (5.6%). Our study showed most of the isolates was resistant to commonly used penicillin and cephalosporin group of antibiotics and also showed 52% prevalence of ESBL producers. Judicious use of antibiotics, detection and reporting of beta-lactamase enzymes helps in combating spread of MDR bacteria and also helps in appropriate treatment.