Risk Factors for Postoperative Urinary Tract Infections in Paediatric Hydronephrosis: A Retrospective Analysis

Background: Paediatric hydronephrosis frequently necessitates surgical intervention. However, postoperative urinary tract infections (UTIs) are common and challenging. This retrospective cohort study aimed to identify UTI risk factors following an operation for paediatric hydronephrosis. Methods: Paediatric patients with hydronephrosis who underwent operation from January to December 2023 were studied. Patients were categorised into no UTI and UTI groups. Demographics, surgical history, pre/postoperative factors, imaging, and lab values were compared. Results: A total of 111 patients were enrolled, with 98 in the no-UTI group and 13 in the UTI group. The UTI group had significantly more previous surgeries and longer surgical duration (p < 0.05). Preoperative factors associated with UTI occurrence included higher hydronephrosis grade, absence of antibiotic prophylaxis, presence of vesicoureteral reflux (VUR), abnormal preoperative urine cultures, and ureteral stent placement (p < 0.05). The UTI group exhibited more extended hospital stays, higher rates of postoperative fever, reoperation, and readmission within 30 days (p < 0.05). Postoperative imaging and laboratory findings were also significantly different (p < 0.05). The UTI group had elevated white blood cell count, C-reactive protein levels, serum creatinine, and urine white blood cell count (p < 0.05). Other potential risk factors included constipation, family history of UTI, bladder dysfunction, history of recurrent UTI, and use of prophylactic antibiotics. Multivariate logistic regression analysis indicated that while antibiotic prophylaxis and preoperative urine culture results negatively correlated with UTI occurrence, other factors were positively correlated, with the number of previous surgeries having the most significant impact on UTI occurrence (odds ratio (OR) = 20.617; 95% confidence interval (CI): [0.718, 0.802]; p < 0.001). Conclusions: Multiple factors contribute to the risk of postoperative UTI for paediatric hydronephrosis, highlighting the need for tailored interventions to mitigate risks and improve outcomes.