Evaluation of surgical site infections along with the study of antibiogram and drug-resistant isolates from exudate samples in a tertiary care hospital

Abstract

Abstract Background: Infections of the skin and soft tissue caused by pyogenic bacteria, are a major cause of morbidity, prolonged hospital stay and post-surgical complications. Present study was designed to determine the rate of surgical site infection (SSI), burden of multi drug resistant (MDR) isolates in exudate samples and to study the antimicrobial resistance and susceptibility pattern among these isolates. Methods: One thousand five hundred and seven pus samples from pyogenic infections and SSI received over 1 year in a microbiology laboratory, which yielded aerobic growth, were identified by standard culture methods and biochemical reactions. Antibiotic susceptibility test and determination of extended-spectrum beta-lactamase (ESBL) and methicillin-resistant staphylococci [methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant coagulase-negative Staphylococci (MRCoNS)] rates was done according to the Clinical and Laboratory Standards Institute guidelines. SSI rates of the hospital were determined. Results: Staphylococcus aureus, Klebsiella, Pseudomonas and methicillin-resistant coagulase-negative staphylococci were the most common organisms isolated from pyogenic lesions. SSI rate was 5.9%. Susceptibility of Gram-negative bacteria to imipenem was 88%, amikacin 86%, gentamicin 83% and piperacillin/tazobactam 80%. Susceptibility was least for cephalosporins 54%, ciprofloxacin 39% and ampicillin 28%. ESBL rate was 33% and MRSA was 38%. In SSI, ESBL and MRSA rates were 35% and 43%, respectively. Among Gram positives, susceptibility to linezolid was 100% and clindamycin 71% susceptible. It was least to ciprofloxacin 19% and co-trimoxazole 24.6%. Conclusions: Developing antibiogram helps in framing local antibiotic policy and adhering to this contributes to controlling drug-resistant strains and also aids in reducing SSI rates.