Aim: To demonstrate the use of non-contrast CT KUB in the detection of abdominal pathologies other than stones, whether or not simulating the clinical picture of urolithiasis, and its impact upon patient management.

Methodology: This was a cross sectional observational study carried out in Radiology department of Rehman Medical Institute Peshawar from Dec 2012 to May 2018. 2776 patients coming for CT KUB were included. Age range was 10 to 90 years and patients presented with persistent or recurrent pain in flanks. Data was collected from the hospital. CT KUB was performed for all patients on 128 slice Toshiba Multidetector computed tomography machine. Intravenous contrast was not given. The CT procedure used exposure factors set at 120 kVp. The radiology reports were reviewed retrospectively, and findings outside the urinary tract (kidneys, ureters, bladder, and urethra) were recorded and categorized by organ system. The encountered abdominal and pelvic pathologies other than stones were divided into two groups: incidental findings and acute pathologies.

Results: In 2776 patients who had CT KUB for suspected urolithiasis, 236 (8.5%) had alternative diagnoses non- GU findings, besides urolithiasis and obstruction, there were 63% males and 37% females. Majority patients were in the age group 21-40 years followed by age group of 41-60 years. The encountered acute abdominal non-renal pathologies were pancreatitis in 15, appendix related pathologies in 46, cholelithiasis in 108, cholecystitis in 1, epiploic appendagitis in 8 and hernia in 58 patients. Other non-KUB findings included psoas abscess (2), bowel perforation (2), Liver masses (1), Bone metastasis(2), Dermoid ovarian cysts (2, one of which had torsion), cervical stenosis with fluid distended uterine cavity (1), Prostate mass (2), uterine fibroids, adrenal adenomas(2) and many with degenerative bone changes, few with osteoporotic collapse. Significant findings were also observed as incidentally noted findings in visualized lower chest sections like pleural effusions, pulmonary nodules and a malignant looking basal lung mass in one case.

Conclusion: 8.5% patients were diagnosed with non-renal acute pathologies on non-contrast CT scan, which required immediate intervention. Non-contrast CT scan of the urinary tract (stone protocol) is a valuable tool in the detection of incidental findings which may simulate, or coincide with urolithiasis and it has a significant impact upon the management of the patients.

Key words: non-contrast CT KUB, urolithiasis, non-renal pathologies