Evaluation of Enterobacteriaceae Resistance to Broad-spectrum Cephalosporins in Patients with Infection following open heart surgery in Shahid Madani Hospital

Background: Increasie in bacterial resistance to broad spectrum antibiotics constitutes a major challenge in medicine. Enterobacteriaceae are among the important causes of nosocomial infections and mortality. This study was performed to evaluate the enterobacteriaceae resistance rate to broad spectrum Cephalosporins in Shahid Madani Heart Center and to determine the optimal antibiotic regimen for such cases. Methods: In a cross-sectional descriptive study, 100 patients from heart surgery wards who were diagnosed with enterobacteriaceae infection in Shahid Madani hospital in 2009 were enrolled. After determination of bacteria type in microbiology laboratory by standard methods, the resistance of bacteria to cephalosporins were evaluated by disc diffusion agar method. Results: Resistance rate of enterobacteriaceae for ceftriaxone, ceftazidime, cefixime, cefotaxime, ceftizoxime and cefepime were 33%, 38%, 29%, 20%, 3% and 5% respectively. Among the third generation cephalosporins, ceftizoxime with a 3% resistance rate was found to be the most effectives and ceftazidime with 38% resistance rate the least effective. Ninety four percent of enterobactriaceae were sensitive to cefepime, a fourth generation cephalosporin. Conclusion: This study shows that third and fourth generation cephalosporin are more effective than first generations in the treatment of enterobacteriaceae infection among open heart surgery patients. A higher rate of resistance was reported in this study compared to the previous studies.