Antibiotic sensitivity pattern of Salmonella serotypes in patients with enteric fever in a teaching hospital

ABSTRACT

To determine the sensitivity of salmonella serotypes to antibiotics in patients with enteric fever. This descriptive study was carried out in medical units of Lady Reading Hospital Peshawar from January 2008 to December 2011. Patients were included by consecutive sampling technique. Blood samples were collected from patients with clinically suspected enteric fever and were sent to hospital laboratory for culture and sensitivity[C/S]. Salmonella colonies were identified using standard biochemical tests including fermentation of glucose, negative urease reaction, lysine decarboxylase, negative indole test, H2S production, and fermentation of dulcitol. Serological confirmation tests included polyvalent antisera for flagellar and somatic antigens. Antibiotic susceptibility was checked by Kirby- Bauer disc diffusion method for 22 antibiotics. Blood cultures of 106[61%] patients out of 173 patients were positive for salmonella species. Salmonella Typhi was found in 54.7% while salmonella paratyphi A in 32.1% and B in 13.2%. The sensitivity of salmonella species for ceftriaxone and ceftazidime was found to be 100%, followed by imipenem[98.1%] and meropenem [96.2%]. The sensitivity of drugs like amoxicillin, chloramphenicol and co-trimaxazolewere 2.8%, 12.3% and 22.6% respectively. Regarding quinolones, most sensitive was moxifloxacin49.1%, followed by ciprofloxacin 48.1%. Salmonella typhi was fully sensitive to meropenum, ceftriaxoneand cetazidime while paratyphi A or B was fully sensitive to ceftriaxone, ceftazidime and imipenem. The sensitivity of salmonella species was very low to the first line agents such as amoxicillin, chloramphenicol and co-trimaxazole. Salmonella species were fully sensitive to third generation cephalosporins such as ceftriaxone and ceftazidime