DIAGNOSTIC ACCURACY OF X-RAY KUB ((KIDNEY, URETER, BLADDER) IN DETECTING URETEROLITHIASIS USING CT SCAN AS GOLD STANDARD

Abstract

Objective

To determine   diagnostic accuracy of X-ray KUB in detecting ureterolithiasis using CT scan as   gold standard.

Methods:

Cross-sectional validation study was conducted at Pakistan Kidney and Liver Institute and Research Centre; data collection was done between March to June, 2025.   total of 362 patients aged 20–60 years with clinical suspicion of ureteric colic were included. All patients underwent X-ray KUB followed by NCCT KUB. Diagnostic indices were calculated using   2×2 contingency table.

Results:

Out of 362 patients, CT scan confirmed ureterolithiasis in 148 (40.9%). X-ray KUB showed sensitivity of 64.2%, specificity of 81.3%, positive predictive value of 72.1%, negative predictive value of 75.8%, and overall diagnostic accuracy of 74.0%.

Conclusion:

X-ray KUB demonstrates moderate diagnostic accuracy and may be used as   initial screening tool in suspected ureterolithiasis, particularly in resource-limited settings, but cannot replace CT scan for definitive diagnosis.