Diagnostic Accuracy of Magnetic Resonance Urography Compared With Computed Tomography Urography in Patients With Hematuria.

Background Hematuria is an important clinical finding that may reflect a wide spectrum of urinary tract abnormalities, ranging from infection and urolithiasis to renal masses and urothelial malignancy. CT urography (CTU) is widely used for the evaluation of hematuria, but magnetic resonance urography (MRU) offers a radiation-free alternative. This study aimed to evaluate the diagnostic performance of MRU compared with CTU in patients presenting with hematuria. Methods This prospective cross-sectional observational diagnostic accuracy study included 35 patients with hematuria who underwent both CTU and MRU as part of their diagnostic evaluation at a tertiary care teaching hospital over 18 months. Imaging findings were analyzed for lesion detection and etiological classification. The final diagnosis was established using a composite reference standard based on imaging findings, clinical assessment, laboratory data, and available operative, histopathological, or follow-up information. Sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy, and concordance between CTU and MRU were assessed. Results The study population included 21 males and 14 females, with a mean age of 45.09 ± 10.91 years. The most frequent etiologies were infection in nine patients, renal mass in eight patients, urothelial carcinoma in seven patients, and urolithiasis in six patients. CTU identified all 30 patients with urinary tract pathology and correctly classified all five patients without demonstrable pathology in this cohort. MRU identified 26 of 30 patients with urinary tract pathology and correctly classified all five patients without demonstrable pathology. MRU showed a sensitivity of 86.7%, specificity of 100.0%, positive predictive value of 100.0%, and negative predictive value of 55.6%. Agreement between CTU and MRU was substantial, with an observed agreement of 88.6% and a Cohen's kappa coefficient of 0.65. Discordant cases were positive on CTU but negative on MRU, mainly reflecting reduced detection of selected urothelial lesions on MRU. Conclusions In this cohort, CTU showed the highest diagnostic performance for evaluating hematuria and provided comprehensive detection across the observed etiological spectrum. MRU demonstrated high specificity and substantial concordance with CTU, supporting its role as a useful radiation-free alternative in selected patients, particularly when radiation exposure or iodinated contrast administration is a concern. However, negative MRU findings should be interpreted with caution when clinical suspicion remains high. A patient-specific imaging approach may help balance diagnostic yield with safety considerations.