ERS3032. Frequency of Genitourinary Abnormalities on CT Urography in Patients without Known Malignancy
Authors * Denotes Presenting Author
  1. Taylor Morris *; University of Wisconsin
  2. Lu Mao; University of Wisconsin
  3. Andrew Wentland ; University of Wisconsin
The purpose of this study was to evaluate the frequency of genitourinary abnormalities identified on three-phase and split-bolus CT urography (CTU).?

Materials and Methods:
Three-phase and split-bolus CTU examinations performed between 2006 and 2021 were curated from our institutional database. Examinations were excluded if the patient had a known or suspected genitourinary neoplasm based on another imaging examination. The ordering indication was recorded for each examination. The CTU reports were used to identify documented genitourinary etiologies. Patient demographics were tabulated. Fisher’s exact tests were used to resolve whether no imaging finding was more frequent with gross versus microscopic hematuria and whether etiologic frequency was different based on gender or between split bolus and 3-phase CTU techniques (p <0.05).

152 studies were included after pre-determined exclusions were made. Most studies were ordered for the indication of hematuria (n=114). The remaining studies were ordered for pain (n=14), recurrent UTI (n=6), chronic kidney disease (n=4), pyelonephritis (n=2), obstructive uropathy (n=2), vomiting (n=1), elevated hemoglobin (n=1), weight loss (n=1), ureteropelvic junction obstruction (n=1), lytic bone lesion in absence of known malignancy (n=1), hydronephrosis (n=1), bladder outlet obstruction (n=1), concern for renal mass (n=1), bacteremia (n=1), and dysuria (n=1).? No genitourinary abnormality was identified in 40% of the cohort. Urolithiasis was identified in 26% of cases. Etiologies seen less frequently included bladder lesions (9%), prostatomegaly (8%), bladder wall thickening (4%), renal masses (8%), and compound renal collecting systems (2%). There were single cases of a hyperdense cyst, ureteral mass, and congenital UPJ obstruction.? The absence of a genitourinary abnormality was significantly more common than finding the above etiologies (p=0.015). The absence of an abnormality was equally likely to occur whether the scan was for gross versus microscopic hematuria, regardless of gender, and in 3-phase versus split-bolus CTU. No significant difference was found (p>0.05) in identifying stones or masses between males and females or between 3-phase and split-bolus CTU.

CTU examinations performed in patients without a diagnosis of malignancy most commonly have no identifiable genitourinary abnormality. Of the possible etiologies, urolithiasis was the most common abnormality identified in this cohort.