Increasing Azithromycin resistance Salmonella bacteremia in pediatric population in a secondary care center in India

Abstract

Background: Typhoid fever is an endemic bacterial infection with high morbidity and mortality. It remains a significant health problem in south East Asia and Africa affecting children and lower socioeconomic strata. Due to the emergence of resistance to first line antibiotics (ampicillin, cotrimoxazole and chloramphenicol), Azithromycin and third generation Cephalosporins are increasingly being used in the treatment of invasive Salmonella infections. Rising incidence of cephalosporin and azithromycin resistance in Salmonella is of significant concern in developing countries like India. Errant use of Azithromycin in upper respiratory tract infections and over the counter availability of drug without prescription also add to the woes. Methods and materials: A retrospective analysis of all samples received for blood culture from April 2018 to September 2018 was done. Clinical, demographic and antimicrobial sensitivity pattern were studied in the pediatric population (<12 years) having Salmonella bacteremia from the medical record department. Blood culture was done with BD Bactec™ 9050 Blood Culture System. Antibiotic susceptibility testing was done with Kirby-Bauer disc diffusion method and Zone diameter was interpreted as per CLSI 2018. Results: Out of the 452 samples received in the laboratory, 139 beeped positive (positivity rate – 30.75%). Out of the total 139 positive cultures, 111 (79.8%) were of pediatric age and among these, 60 were having Salmonella bacteremia. Most of the patients were from ward 34 (56.7%) f/b OPD 24 (58.3%) and 2 from NICU (3.3%). Male predominance were seen 32 (53.3%). Most of the patients were admitted with fever (59, 98.3%) and 7 (11.7%) were presented with Acute Gastroenteritis. Mean age of the population was 7.7 years. Median time to Bacteremia was 2 days (range: 0–4). Salmonella resistance to Azithromycin was seen in 73.3% (n = 44) and for Ciprofloxacin was 30%(n = 18) whereas ampicillin sensitivity was 81.2% (n = 49) and 3rd generation cephalosporins were 97% (n = 58) sensitive. Conclusion: Knowledge of the antibiotic resistance pattern serves as a significant platform in improving the empirical antibiotic therapy. There is a need for continuous surveillance of antimicrobial susceptibility pattern. Resistance rates in Salmonella spp. are alarming, in particular for azithromycin and ciprofloxacin. This warrants nationwide surveillance and revision of treatment guidelines.