<b>Examination of Renal Hydronephrosis on Diagnostic Ultrasound and Their Common Causes in Adults</b>

Background: Hydronephrosis is a clinically important manifestation of impaired urinary drainage that may progress to renal dysfunction if the underlying obstruction is not identified and managed promptly. Ultrasonography is widely used as a first-line imaging modality because it is non-invasive, accessible, radiation-free, and capable of detecting collecting-system dilatation and associated urinary tract abnormalities. Objective: To evaluate the sonographic findings and common causes of renal hydronephrosis among adult patients undergoing diagnostic ultrasound examination. Methods: This descriptive cross-sectional study was conducted in the Department of Radiology, Allied Hospital, Faisalabad, from June to September 2022. A total of 50 adult patients aged 21–60 years with sonographic evidence of hydronephrosis were included through convenience sampling. Demographic data, presenting complaints, clinical observations, ultrasonographic findings, and final diagnoses were recorded using a structured proforma. Data were analyzed using SPSS version 16, and categorical variables were summarized as frequencies and percentages. Results: Of 50 patients, 26 (52.0%) were male and 24 (48.0%) were female. Most patients were aged 21–40 years, accounting for 31 cases (62.0%). The most common presenting complaint was right loin pain in 10 patients (20.0%). The leading ultrasound findings were right renal mild hydronephrosis in 15 patients (30.0%), hydroureter in 10 patients (20.0%), and bilateral mild hydronephrosis in 7 patients (14.0%). Stone-related obstruction was the dominant diagnostic category, accounting for 39 patients (78.0%), with right lower ureteric stone with renal stone in 12 patients (24.0%), right lower ureteric stone alone in 11 patients (22.0%), and left lower ureteric stone in 6 patients (12.0%). Conclusion: Ultrasonography effectively identified hydronephrosis and its associated causes, with ureteric and renal calculi forming the principal diagnostic burden among adult patients