EMERGING RESISTANCE

Objectives: To study the bacteriological profile of enteric fever and their antibioticsensitivity pattern to commonly used antibiotics in view of emerging resistance at Civil HospitalKarachi (C.H.K.) and provide a guideline for making a protocol for empirical antibiotic therapywhere culture facilities are not available. Methodology: Design: Descriptive laboratory Basedstudy. Place and Duration of study: The study was conducted from 1st January, 2010 till 30thJune, 2012 at the Central Lab, Civil Hospital Karachi. Patients and Methods: A cross sectionalanalysis was done on a total of 37,805 blood specimens sent for C/S from the entire inpatient andoutpatient departments to the central lab, CHK. All blood cultures were inoculated in thioglycolatebroth and incubated at 37° for 7 days. Positive blood cultures were processed, colonies wereidentified using standard biochemical tests and antibiotic susceptibility was checked by Kirby-Bauer disc diffusion method as per CLSI criteria. Results: Out of these specimens, 430 sampleswere found positive for the salmonella strains, among them 395 (91.86%) were Salmonella typhiand 35 (8.14%) were Salmonella paratyphi A. Salmonella infection was more common in male(55.85%) and more prevalent in children under 10 years of age (34.88%). The resistance patternfor Amoxicillin, Chloramphenicol, Co-trimoxazole, was (29%), (41%) and (5%) respectively;while the resistance was found to be higher in the commonly prescribed drugs belonging to firstand second generation of cephalosporins and flouroquinolones. Conclusion: Amoxicillin andChloramphenicol, the first line of drugs for the treatment of enteric fever are losing their efficacyand most of the organisms have developed resistance. Also, resistance against the second lineof therapy, involving the use of cephalosporins and quinolones is rapidly emerging.