The Role of Renal Ultrasonography in Asymptomatic Microscopic Hematuria

Hong, Jeong Hee; Kim, Eun Tak; Jeon, Seong Soo; Park, Kwan Hyun; Lee, Kyu Sung; Lee, Sung Won; Choi, Han Yong; Choi, Yoon Ho; Chai, Soo Eung

Abstract

PURPOSE: Serious urologic lesions have been reported in 4.8% to 16.5% of patients referred for asymptomatic microscopic hematuria. This study aimed to demonstrate the cause of microscopic hematuria and to evaluate the diagnostic efficacy of urologic workup methods.
MATERIALS AND METHODS
Between February 1995 and July 1999, 970 patients with asymptomatic microscopic hematuria were examined by urinalysis, urine culture, intravenous pyelography and renal ultrasonography. Patients with proterinuria of 2+ or more and RBC casts were excluded from the study. Average patient age was 53 years (20-82 years). The male-to-female ratio was approximately 1:1 (473:497).
RESULTS
Among 970 patients with asymptomatic microscopic hematuria, the cause was detected in 96 patients, including 2 renal cell carcinoma and 2 bladder tumor. In patients over the age of 50 years, the incidence of malignancy was 6.6% (4/610) and higher incidence of significant lesions was found (11.0%) compared to patients under the age of 50 (8.1%). Malignancy was not found in any of the 360 patients under the age of 50 years. Neither the degree of hematuria nor sexual difference correlates with clinically significant lesions. In 96 patients with significant lesions, the detection rate of abnormalities by renal ultrasonography and IVP was 26% (25/96) and 12.5% (12/96), respectively (p=0.004).
CONCLUSIONS
Our report has shown that 9.9% of the patients had significant urologic lesions including 4 malignancies. We demonstrate that renal ultrasonography was more beneficial than IVP for the evaluation of the upper tract in patients with asymptomatic microscopic hematuria. It may be more appropriate to consider renal ultrasonography in addition to IVP as an initial examination in the evaluation of microscopic hematuria.