Culture and sensitivity of Salmonella species: analysis of a two year data

To determine the proportion and culture/sensitivity (C/S), pattern of different species of Salmonella in blood sent for C/S in a laboratory at a tertiary care hospital.

A retrospective analysis was done on all blood samples sent for C/S to the laboratory of Ziauddin Medical University Hospital during two years period (Jan 1, 1998 to Dec 31, 1999). 9035 blood samples were received for C/S. All blood cultures were inoculated in thioglycolate broth and incubated at 37 degrees for 7 days. Positive blood cultures were processed, colonies were identified using standard biochemical tests and antibiotic susceptibility was checked by Kirby-Bauer disc diffusion method.

Three hundred and four (3.4%), out of 9035 blood cultures were positive for Salmonella, among them 220 (72%) were S. typhi, 82 (27%) paratyphi A or B and remaining were other species. Salmonella infection was more common in male (58%) and more prevalent in children under 10 years of age (58%). Ampicillin, chloramphenicol, cotrimoxazole resistance was (46.5%), (39.3%) and (44.8%) respectively.

Ampicillin chloramphenicol and cotrimoxazole, the first line of drugs for the treatment of infection are losing their efficacy and most of the organisms have developed resistance against these drugs.