Bacterial Agents and Antibiotic Resistance Profile in Pyelonephritis; A Comparison between Children with and without Urinary Tract Abnormalities in the North of Iran

Background: Pyelonephritis in children is a serious condition that is commonly encountered in clinical practice. Urinary tract abnormalities increase the risk of urinary tract infections (UTIs) and consequently antibiotic resistance. Our study aimed to evaluate the local trend in terms of bacterial uropathogen resistance in Babol, Iran, in children with pyelonephritis considering urinary tract abnormalities. Methods: We recruited pediatric cases aged 1 month to 18 years who were admitted to Amirkola hospital with a diagnosis of pyelonephritis from 2016 to 2019. Children with negative urine cultures or incomplete imaging were excluded from the study. Causative agents were identified based on biochemical features. Antimicrobial in vitro resistance tests were performed using the disk diffusion agar test. Results: A total of 105 children were included in the study. E. coli was the most common causative agent found in 93 (88.6%) patients. Most of the bacterial isolates were sensitive to amikacin and imipenem, and only 12.4% and 13.3% of isolates were resistant to this antibiotic. On the other hand, nalidixic acid represented the least effective treatment, with a resistance rate of 88.6%. A statistically significant difference was observed in resistance to nitrofurantoin and nalidixic acid between children with and without anomalies (p < 0.05). Conclusion: High antibiotic resistance, especially in children with urinary tract anomalies, was identified for frequently used antibiotics. Our findings provide important implications regarding local patterns of uropathogens and antibiotic resistance in children with pyelonephritis.