Objective:

To determine the concordance between ultrasonography and computed tomography (CT) urography for the screening of and early diagnosis in patients suspected of presenting with urolithiasis.

Materials and methods:

A total of 140 patients above 18 years of age and with clinical suspicion of urolithiasis were studied. Ultrasound imaging was performed to determine the presence and size of the stone. The patients later underwent single-phase CT urography to determine stone location, size, and density. Concordance between ultrasonography and CT urography was estimated, along with the sensitivity and specificity of the two imaging methods.

Results:

Through CT urography, kidney stones were observed in 94 patients, ureteral stones in 26 patients, and bladder stones in 20 patients. In comparison, ultrasonography identified 84% (79/94 patients) of the kidney stones, 84.6% (22/26) of the ureteral stones, and 100% (20/20) of the bladder stones. The estimated concordance between the two imaging methods was 61% (88% sensitivity, 90% specificity) in the kidneys, 75% (95% sensitivity, 90% specificity) in the ureters, and 98% (99% sensitivity and specificity) in the bladder.

Conclusions:

Ultrasonography is a reliable tool for early diagnosis in patients with clinical suspicion of urolithiasis, as long as it is performed by specialized personnel.