Spontaneous Upper Urinary Tract Rupture Caused by Ureteric Stones: Clinical Characteristics and Validation of a...

Area of Science:

• Radiology
• Urology
• Medical Imaging

Background:

• Spontaneous upper urinary tract rupture (sUUTR) requires accurate classification for effective management.
• Current radiological assessment methods for sUUTR need validation.
• Understanding the clinical and radiological correlates of sUUTR is crucial.

Purpose of the Study:

• To validate a radiological classification system for spontaneous upper urinary tract rupture (sUUTR).
• To analyze the relationship between sUUTR classification and clinical, laboratory, and radiological characteristics.
• To assess the feasibility of conservative treatment based on radiological findings.

Main Methods:

• Analysis of 66 patients with computerised tomography (CT)-proven sUUTR.
• Radiological classification of sUUTR into local spread, free fluid, and urinoma by experienced radiologists and a urologist.
• Evaluation of interobserver agreement using Intraclass Correlation Coefficient (ICC) and Cohen's Kappa.
• Logistic regression models to determine associations between clinical variables and sUUTR severity.

Main Results:

• High interobserver agreement (Kappa > 0.7) and interrater reliability (ICC 0.82) for the sUUTR classification system.
• Local spread observed in 36.4%, free fluid in 59.1%, and urinoma in 4.5% of cases.
• Patients with free fluid/urinoma had a higher Charlson Comorbidity Index (CCI) (40.5%) compared to local spread (16.7%) (p=0.04).
• Absence of intraoperative urine extravasation was more frequent in local spread (66.7%) versus free fluid/urinoma (28.6%) (p<0.01).
• Local spread was associated with absence of contrast medium extravasation (OR 4.5, p<0.01).

Conclusions:

• The validated sUUTR classification system demonstrates good inter/intra-reader reliability.
• Absence of urine extravasation is significantly more common in sUUTR with local spread.
• This finding supports the potential for conservative management in cases of sUUTR with local spread.