Prevalence of multi-drug resistant bacterial pathogens among body fluids

ABSTRACT Objectives: The aim of the present research study was to evaluate the prevalence and antibiotic resistance pattern of the scarcely investigated invasive pathogens causing body fluid infections. Design: The study was conducted in the Department of Microbiology, University of Karachi, from July-December 2013. Methods: In this study 21 samples of body fluids were collected from different hospitals and pathologic laboratories of Karachi, among which 11 samples were of peritoneal fluid, 8 of pleural fluid and 2 of cerebrospinal fluid. Isolates were tested against gentamicin, ciprofloxacin, cefotaxime, ceftriaxone, erythromycin, penicillin G, Amoxycillin/clavulanic acid and amikacin through Kirby-Bauer disk diffusion method for antibiotic susceptibility testing and broth macrodilution technique was performed to determine their minimum inhibitory concentration (MIC) levels. Results: Gram negative organisms were isolated pre-dominantly (86%) from these specimens. The most frequent gram negative organism was Pseudomonas aeruginosa (28%) followed by Klebsiella pneumonia (24%) and Escherichia coli (19%). Resistance to Amoxycillin/clavulanic acid was 86%, gentamicin, cefotaxime, ceftriaxone was 57%, ciprofloxacin 43% while the least resistance was for amikacin i.e. 24%. MIC of the antibiotics among isolated pathogens indicated a high level of resistance against Cefotaxime, Ceftriaxone and Amoxicillin-clavulanic acid (>1024 µg/mL) while 1024 µg/ml against Gentamicin. Altogether, 71% pathogens isolated in this study were resistant to more than one antibiotic. Discussion and Conclusion: The results of this study indicate that amoxicillin/clavulanic acid and third generation cephalosporins have decreased their efficacy for the empirical treatment of spontaneous bacterial peritonitis. The reason for this increased resistance among invasive pathogens might be linked with the emergence of multi drug resistance among the normal flora of bowel.