Analysis of renal biopsies performed in 208 patients with asymptomatic urinary abnormalities

Cho, Ji Hyung; Jang, Min Hwa; Cho, Young Jun; Park, Sun Hee; Cho, Dong Kyu; Kim, Sung Ho; Hwang, Jung Ha; Cho, Kyu Hyang; Do, Jun Young; Yoon, Kyung Woo; Kim, Yong Lim

Abstract

BACKGROUND: Asymptomatic urinary abnormalities are one of the most frequent abnormalities in clinical nephrology. However, there are few large-scaled studies about the clinical manifestations and the pathologic findings of the disease. The aim of present study was to evaluate the clinicopathologic nature of the patients with asymptomatic urinary abnormality proven by renal biopsy.
METHODS
Between January 1998 and July 2002, two hundred and eight patients with asymptomatic urinary abnormality at three hospitals in Daegu were studied for age, sex, initial urinary findings, serum creatinine, daily urine protein and pathologic findings by renal biopsy.
RESULTS
Mean age was 28.0 years (range 14-60 years) at diagnosis of 208 patients and sex ratio of male to female was 141:67. One hundred and two patients (49.0%) had hematuria and proteinuria, 94 (45.2%) had pure microscopic hematuria and the remaining 12 (5.8%) had isolated proteinuria. Pure microscopic hematuria was the dominant urinary abnormality in younger patients. In pathologic findings, 120 patients (57.7%) were IgA nephropathy, 35 (16.8%) thin glomerular basement membrane disease, 8 (3.8%) minimal change disease, 6 (2.9%) membranous glomerulonephropathy and 22 (10.6%) showed no histologic abnormality. The most common pathologic diagnosis in all three groups was IgA nephropathy. In pure microscopic hematuria group, 38 patients (40.4%) were IgA nephropathy and 27 patients (28.7%) were thin glomerular basement membrane disease. There were no significant difference in pathologic findings depending on the severity of proteinuria (p>0.05).
CONCLUSION
In our study, the most common cause of asymptomatic urinary abnormalities was IgA nephropathy. In patients with pure microscopic hematuria, IgA nephropathy and thin glomerular basement membrane disease were two leading causes.