Is Kidney-Ureter-Bladder Radiography Still a Helpful Tool to Address Acute Ureteral Colic in Emergency Settings?

Background This study aims to identify the reliability of kidney-ureter-bladder (KUB) radiography as a triage tool in acute ureteral colic (AUC). Moreover, this article correlates between KUB and non-contrast computerized tomography (NCCT) in view of stone characteristics and clinical outcomes. Methodology A retrospective cohort study recruited patients who had proven ureteric stones on NCCT. A blinded review of KUB and NCCT was performed to identify the following variables in both tests: site, ureteric stone maximum diameter, and stone density. Correlation between KUB radiography and NCCT has been performed. The intermethod reliability was used to measure the degree to which test scores are consistent when the methods or instruments employed vary. Results One hundred fifty-one patients were included, of whom 75 (50%) had negative KUB and positive NCCT results for ureteric stones based on the blinded review. Lower ureteral calculi were found to be the most common location in both KUB (<i>n </i>= 49, 65%) and NCCT images (<i>n </i>= 81, 54%). The median stone diameters of KUB and NCCT were 5 (3-8) mm and 6 (4-9) mm, respectively. Hounsfield unit densities of more than 630 were found in 86 (57%) patients, and radiopaque stones were found in 76 (50%) patients. There was moderate and significant concordance (Cohen's kappa = 0.520) between NCCT and KUB regarding stone location (<i>P </i>< 0.01). There was a strong concordance (Cohen's kappa = 0.804) between NCCT and KUB in detecting ureteric stone maximum diameter (<i>P </i>< 0.01). Stone density was weakly correlated between KUB and NCCT (Cohen's kappa = 0.254) (<i>P </i>= 0.001). Thirty-four cases (45%) of negative KUB results required surgical intervention (SI). Sepsis (<i>n </i>= 5, 15%) and acute kidney injury (<i>n </i>= 23, 68%) were the main indications for SI in negative KUB and positive NCCT ureteric stones. Conclusions KUB radiography should not be used as a triage tool in AUC due to potentially harmful outcomes. However, KUB radiography can be reliably used during follow-up, as there is a strong correlation between KUB radiography and NCCT for KUB-detectable ureteric stones.