Diagnostic Accuracy of Ultrasound and Plain X-Ray KUB (Kidney, Ureter, Bladder) Compared to Non-Contrast CT (Computed Tomography) in Patients of Ureteric Calculi

BACKGROUND Imaging plays a major role in the diagnosis and management of patients with urolithiasis. Non-Contrast Computed Tomography (NCCT) is generally accepted as the gold standard, but there are concerns over higher radiation exposure from NCCT to the patient population. Our prospective study compared the diagnostic accuracy of plain X-ray KUB (Kidney, Ureter, Bladder) and USG (Ultrasonography) with NCCT in the evaluation of patients with ureteric colic. METHODS This study conducted from December 2018 to January 2020 in the Department of Urology, Vijayanagar Institute of Medical Sciences, and attached Hospital. 230 patients with ureteric colic were evaluated for ureteric calculi with x-ray KUB, USG (Ultrasonography) abdomen and pelvis and NCCT (Non-Contrast Computed Tomography) KUB region. RESULTS Out of 230 patients, 168 (73 %) were males and 62 (26.9 %) were females. Ages of the study population ranged from 18 to 55 yrs. 198 of the 230 patients were confirmed to have ureteric calculus, with lower ureteric calculus 97 (48.9 %), upper ureteric 65 (32.8 %), middle ureteric 29 (14.6 %), and multiple 7 (3.5 %). X-ray and USG (Ultrasonography) group yielded a sensitivity of 86.3 %, a specificity of 87.5 %, positive predictive value 97 %, and negative predictive value 51 %. While On NCCT (Non-Contrast Computed Tomography), a total of 192 patients (96 %) demonstrated ureterolithiasis of the 198 patients confirmed to have ureteric calculi (Table 2). X-ray and USG group yielded a sensitivity of 96.9 %, specificity of 93.6 %, positive predictive value 98.9 %, and negative predictive value 83 %. CONCLUSIONS Combination of x-ray KUB and USG, and NCCT were found to be excellent imaging modalities for the detection of ureteric calculi. X-ray KUB and USG can be used as the first investigation of choice for patients with ureteric colic and for follow up of patients after treatment. KEYWORDS Ureteric Colic, Ureterolithiasis, Ultrasonography