Acharya A1, Nepal HP2, Gautam R3 and Shrestha S4
1Associate Professor, 2,3,4Lecturer, Department of Microbiology, Chitwan Medical College Teaching Hospital, Bharatpur, Nepal.
Enteric fever is one of the common clinical conditions in patients presenting to the hospitals. The study was carried out to assess the rate of isolation of common serotypes of enteric fever pathogens and their antimicrobial susceptibility pattern which is of utmost importance to institute effective therapy.
A prospective study was carried out in the Department of Microbiology, Chitwan Medical College Teaching Hospital from 15th June 2009 to 14th June 2010. A total of 4355 blood culture samples from both admitted patients and outpatients of the hospitals were processed by standard microbiological technique to identify the causative agents and their susceptibility pattern to commonly used antimicrobial agents in compliance with CLSI guidelines.
Isolation rate of Salmonella species was 0.96%. Among a total of 42 Salmonella isolates, 24 (57.1%) isolates were Salmonella Paratyphi A and 18 (42.9%) were Salmonella Typhi. Male preponderances were seen in infections caused by both the organisms. On performing antimicrobial susceptibility by Kirby Bauer disc diffusion method, Salmonella Paratyphi A demonstrated 100% susceptibility to Amikacin, Chloramphenicol and Ofloxacin. Similarly, Salmonella Typhi was highly susceptible to Ceftriaxone (94.1%) followed by Ofloxacin (90.9%) and Cephotaxime (90%) and both were least susceptible to Ampicillin (S.Paratyphi A 21.7% and S.Typhi 29.4%). Multidrug resistance was found to be 16.66% among the Salmonella Typhi isolates.
Isolation of Salmonella species is relatively low in Bharatpur. Salmonella Paratyphi A is the most common agent of enteric fever. Moreover, these pathogens have developed resistance to all commonly used antimicrobials.