Review Areas in CT KUB: Think SALT N’ SUGAR
DOI:
https://doi.org/10.69926/qcd23s35Abstract
Objective: To assess the diagnostic yield of CT KUB in terms of renal calculi and alternative diagnoses and create a memory aid for CT KUB review areas
Methodology: After approval from the institutional review board, 139 CT KUB examinations ordered with the indication of renal/ureteric colic were reviewed by 2 consultant radiologists having an extensive experience in emergency radiology. They assessed the scans for urinary tract calculi, their exact location and presence of absence of obstruction. Additional findings outside the urinary tract were also analyzed.
Results: Of the reviewed 139 CT KUB, 77 (55.4%) showed urinary tract calculi and 62 (44.6%) did not reveal urinary tract calculi. Of the 77 CT KUB positive for urinary tract calculi, 36 showed nonobstructive and 41 showed obstructive calculi. The CT KUB showing renal calculi were 35 (46%), those having ureteric calculi were 24 (31%) and the ones revealing both renal and ureteric calculi were 18 (23%). Out of 139 CT KUB, 37 (26.6%) had additional findings outside of urinary tract calculi. Of those, 24 (17.3%) had clinically significant/acute findings, and the other 13 (9.4%) had incidental/non-acute findings. These included urogenital inflammatory conditions, intussusception, appendicitis, osseous fracture, and ovarian mass.
Conclusion: About one-fourth of the CT KUB examinations can show important additional findings outside the urinary tract. The acronym SALT n’ SUGAR will be helpful to remember the non-calculus causes of abdominal pain mimicking renal/ureteric colic. It stands for stranding (fat), appendix, lung bases, terminal ileum, nodes (lymph), skeleton, urogenital (non-calculus), gallbladder, adnexae, and rest of colon.
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