Assessment of factors affecting the prognosis of renal functions inposterior urethral valve patients

The data of 128 male patients who underwent surgery for PUV in the Department of Urology at Hacettepe University Faculty of Medicine between January 1986 and July 2023 were retrospectively examined. Serum creatinine values of the patients were categorized based on age-specific reference values. The patients' ages at the time of surgery, clinical presentations, nadir creatinine levels, the presence of VUR, urinary tract infection and the impact of treatment options on the final creatinine level were evaluated by univariate and multivariate analysis. VUR patients were classified as unilateral and bilateral. SPSS 24.0 (IBM Corp., Chicago) was used for data analysis and p<0.05 was considered statistically significant. The median age of patients at the time of surgical operation was 5 months (1- 144 months) and the median follow-up period was 26 months (3-300 months). Among the 128 patients, 33 (25.8%) had final creatinine levels above the age-specific reference range. When categorized based on VUR status, 52 patients had without VUR, 40 had unilateral VUR, and 36 had bilateral VUR. While the last creatinine values were similar in patients without VUR (19.2%) and with unilateral VUR (17.5%) (p=0.832), it was significantly higher in patients with bilateral VUR (44.4%) compared to others (p=0.011) (p=0.011). When the DMSA and/or MAG3 results of 128 patients were examined, the data of 92 patients were accessed and the presence of atrophic kidneys was determined based on ultrasound findings, data for 16 patients were accessed. Patients with unilateral VUR and ipsilateral renal function <%15 were defined as severe renal dysplasia (VURD). Among these 108 patients, 36 had unilateral VUR and 16 of them were diagnosed with VURD. When patients with and without VURD were analyzed according to current creatinine levels, no statistically significant difference was found between the two groups. vi In univariate analysis: elevated nadir creatinin after initial relief obstruction (p<0.001), nadir creatinine levels above 0.8 mg/dl (p < 0.001), elevated creatinine levels at the age of 1 (p = 0.005), bilateral VUR (p=0.003), persistent hydronephrosis (p = 0.01), initial treatment method other than valve ablation (p=0.016) and presentation with urosepsis (p=0.019) were found to be related with the last creatinine level. In multivariate analysis, elevated nadir creatinin and persistent hydronephrosis were predictive factor for the creatinine at last visit. The nadir serum creatinine value at the time of diagnosis is the most important factor in predicting prognosis in terms of reflecting kidney reserve. Unresolved hyroureteronephrosis was also found as an important prognostic factor. Patients with unilateral VUR, independent of the severity of dysplasia, have a prognosis as favorable as those without VUR. Key words: posterior urethral valves, VURD syndrome, hydronephrosis