An unusually high occurrence of Salmonella enterica serotype paratyphi A in patients with enteric fever.

BACKGROUND & OBJECTIVES: Salmonella enterica serotype Paratyphi A has been reported less frequently as a causative agent of enteric fever. Reports on the antimicrobial susceptibility of this pathogen are few and varied. An unusually high occurrence of S. Paratyphi A was noted in a tertiary care hospital at Nagpur, Maharashtra during April 2001-September 2002. An effort was made to study the antimicrobial susceptibility pattern and phage types of the isolates. METHODS: Blood cultures of patients suspected to have enteric fever admitted to the Indira Gandhi Medical College and Hospital, Nagpur were processed by conventional methods. Antimicrobial susceptibility was tested by Kirby-Bauer disc diffusion method and the minimum inhibitory concentration (MIC) to chloramphenicol was determined. RESULTS: Eighteen (46.15%) of 39 Salmonella isolates were S. Paratyphi A and all were sensitive to ciprofloxacin and cephotaxime. Twelve (66.67%) strains were sensitive to ampicillin and 13 (72.22 %) to chloramphenicol. Two strains (11.11%) were resistant to three drugs (ampicillin, chloramphenicol and cotrimoxazole) simultaneously. The prevalent phage type in the local population was phage type I. INTERPRETATION & CONCLUSION: The high occurrence of S. Paratyphi A found in the present study indicated the emergence of this rare pathogen of enteric fever in the local population. Though some degree of resistance was encountered with ampicillin and chloramphenicol, all the isolates were sensitive to ciprofloxacin, currently a drug of choice for enteric fever. Multidrug resistance was rare.