Investigation of Antibiotic Resistance Pattern of Non-Fermenting Gram-Negative Bacteria Isolated from patients in a referral hospital, Shiraz, Southwest Iran

Aim: Antimicrobial resistance is a global concern. Bacterial resistance to the available antibiotics can lead to increased morbidity and mortality. In this study, we investigated the frequency and antibiotic resistance pattern of non-fermenting gram-negative bacteria Acinetobacter baumannii and Pseudomonas aeroginosa. Methods: This is a cross-sectional study was conducted in a referral hospital, through a questionnaire that contained patients' age, gender, site of the body where sample was taken, severity of microbial growth in culture, type of organism that was found in the culture, and the antibiogram result. Results: A total of 210 patients (7 adults and 203 neonates) were included in this study. The most frequent antibiotics that A. baumannii was resistant to were amikacin (89.4%), ceftazidime (86.5%), gentamicin (70.9%), imipenem (70.9), cefepime (67.4%), ciprofloxacin (60.3%), cotrimoxazole (36.2%), tetracycline (9.9%), and cefotaxime (5.7%). The most frequent antibiotics that P. aeroginosa was resistant to were amikacin (31.9%), gentamicin (31.9%), ceftazidime (29%), cefepime (24.6%), ciprofloxacin (11.6%), and imipenem (10.1%), respectively. Conclusion: The lowest resistance rates of A. baumanni isolates to the studied antibiotics were related to tetracycline and cefotaxime, and the lowest resistance rates of P.aeroginosa isolates were related to imipenem and ciprofloxacin.