High Prevalence of Antibiotic-Resistant Gram-Negative Bacteria Causing Surgical Site Infection in a Tertiary Care Hospital of Northeast India

Background and objective Surgical site infections (SSI) are the most common healthcare-associated infections in low- and middle-income countries associated with substantial morbidity and mortality and impose heavy demands on healthcare resources. We aimed to study the microbiological profile of SSI pathogens and their antibiotic-resistant patterns in a tertiary care teaching hospital serving mostly rural population Methods A prospective, hospital-based cross-sectional study on pathogen profile and drug resistance was conducted from January 2015 to December 2016. Study subjects were the patients who developed signs of SSI after undergoing surgical procedures at three surgical wards (General Surgery, Orthopedics, and Obstetrics & Gynecology). The selection of the patients was based on CDC Module. Standard bacteriological methods were applied for isolation of pathogens and antibiotic-susceptibility testing based on CLSI (Clinical Laboratory Standard Institute) guidelines. Results Out of 518 enrolled subjects, 197 showed growth after aerobic culture yielding 228 pathogen isolates; 12.2% of samples showed polymicrobial growth. Escherichia coli (22.4%) and Klebsiella species (20.6%) were the predominant isolated bacteria followed by Staphylococcus species (18.4%), Pseudomonas species (12.3%), and Enterococcus species (6.6%). Gram-negative bacteria (GNB) were highly resistant to ampicillin (90.1%) and cefazolin (85.9%). High resistance was also observed to mainstay drugs like ceftriaxone (48.4%), cefepime (61%), amoxycillin-clavulanic acid (43.4%), and ciprofloxacin/levofloxacin (37.7%). Among the Gram-positive cocci, Staphylococcus aureus showed 85-96% resistance to penicillin and 65-74% to ampicillin. But GPCs were relatively less resistant to quinolones (16-18%) and macrolides (21.5%). S. aureus was 100% sensitive to vancomycin and clindamycin but vancomycin-resistant Enterococci was encountered in 3/15 (20%) isolates. Conclusion GNBs were responsible for more than two-thirds of aerobic-culture positive SSI and showed high resistance to the commonly used antibiotics thus leaving clinicians with few choices. This necessitates periodic surveillance of causative organisms and their antibiotic-susceptibility pattern to help in formulating hospital antibiotic policy. The antibiotic stewardship program is yet to be adopted in our hospital.