FREQUENCY OF NEGATIVE CT KUB AT A PUBLIC SECTOR TERTIARY CARE HOSPITAL
Main Article Content
Keywords
CT KUB, urolithiasis, renal colic, negative CT, flank pain
Abstract
Background: Computed tomography of the kidneys, ureters, and bladder as non-contrast (CT KUB) is a common method of assessing the possible existence of urolithiasis. Even though it has good diagnostic precision, a significant percentage of radiographies have negative outcomes, raising concerns about unnecessary radiation exposure and resource utilization.
Objective: To determine the frequency of negative CT KUB findings and evaluate associated clinical and radiological characteristics in patients presenting with suspected urolithiasis at a public sector tertiary care hospital.
Methodology: It is a cross-sectional observational study and it was carried out at Jinnah Postgraduate Medical Centre, Karachi, between June and December 2022. The participants were 96 consecutive patients whose clinical impression of urolithiasis was present and whose age was ≥16 years who received non-contrast CT KUB. A structured proforma was used to record the demographic, clinical, laboratory, and radiological variables. The findings were classified as positive or negative of stones using CT. Associations between CT outcomes and specific clinical variables were measured with chi-square tests. The statistical significance was taken to be 0.05.
Results: Of the 96 patients, 65 (67.7%) had CT-confirmed urolithiasis, while 31 (32.3%) had negative CT KUB findings. Among CT-positive patients, bilateral stones were most frequent (36.9%), and the kidney was the commonest site (26.2%). The mean stone size was 7.34 ± 3.48 mm. In CT-negative cases, lumbar spondylosis (25.8%), hydronephrosis without visible calculus (22.6%), and appendicitis (19.4%) were the most frequent alternative diagnoses. No statistically significant association was observed between CT KUB result and clinical variables; fever showed a borderline association (p = 0.097).
Conclusion: Nearly one-third of CT KUB scans were negative, frequently revealing alternative diagnoses. These findings support the diagnostic utility of CT KUB while highlighting the need for rational imaging strategies to optimize resource use and minimize radiation exposure.
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This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
All articles published in JPTCP are licensed under Copyright Creative Commons Attribution-NonCommercial 4.0 International License.
Madiha Saleem Rehmani
Senior Registrar, Department of Urology, Hamdard University hospital, Karachi, Pakistan
Anum Fatima Parekh
Senior Lecturer, Department of Urology, Sindh Institute of Urology and Transplant, Karachi, Pakistan
Akhtar
Consultant, Department of Urology, Dr Sikander Ali Mandhro Hospital, Badin, Pakistan
Suhail Akhtar Channa
Assistant Professor, Department of Urology, Benazir Institute of Urology and Transplant, Nawabshah, Pakistan
Muhammad Zohaib Zafar Khan
Senior Registrar, Department of Urology, United Medical & Dental College, Karachi, Pakistan
Shahzad Ali
FCPS Urology, FRCS. Glasgow, FACS. USA, Professor of Urology, Department of Urology, Jinnah Sindh Medical University, Karachi, Pakistan
