Absence of multidrug resistance in Salmonella enterica serotypes Typhi and Paratyphi A isolates with intermediate susceptibility to ciprofloxacin.

Background: We describe the antimicrobial susceptibility pattern of 64 blood stream isolates of Salmonella enterica serotypes Typhi and Paratyphi A studied from January 2013 to December 2014 at a tertiary care centre in North India. Methods: Isolates were identified by standard biochemical reactions and confirmed by slide agglutination using specific antisera. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion method and by E-test. Results: In this study, 92% (46/50) of Salmonella Typhi and all Paratyphi A (n=14) isolates were susceptible to ampicillin, chloramphenicol and cotrimoxazole. Eighty percent of Typhi (40/50) and 64% (9/14) of Paratyphi A were intermediately susceptible to ciprofloxacin. Nineteen percent (12/64) of isolates were resistant to ciprofloxacin. No resistance to ceftriaxone and azithromycin was detected. Conclusions: Our study adds to the current knowledge of world-wide reports of multidrug resistance in S. Typhi.