The clinicopathological characteristics of thin basement membrane nephropathy with proteinuria in adult / 대한내과학회지

ABSTRACT

BACKGROUND: Proteinuria is rarely observed in patients who suffer from thin basement membrane nephropathy (TBMN). Our study was performed to evaluate the clinical characteristics and prognosis of TBMN patients with proteinuria. METHODS: We conducted a retrospective study on 231 kidney biopsies. A urine protein level more than 500 mg for the 24-hour urine excretion was considered as significant proteinuria. We studied the clinical characteristics, the pathological findings and the response to treatment of these patients. RESULTS: Ten (4 males and 6 females) of 17 cases of TBMN had significant proteinuria (59%). The mean patient age was 35 years. Six patients had hypertension and 1 patient had nephrotic syndrome. Two patients had proteinuria only, and 8 patients had both hematuria and proteinuria. At the time of biopsy, the amount of urine protein was 1,881 mg per day, and all the patients except one showed normal renal function. The GBM thickness ranged from 201 to 252 nm. Nine patients were treated with angiotensin receptor blocker, and 1 patient suffering from nephrotic syndrome was treated with prednisolone and cyclophosphamide. Marked improvement of the proteinuria (659 mg per day) was observed in 8 patients during the follow-up period. CONCLUSIONS: Thin basement membrane nephropathy is one of the causes of proteinuria. Therefore, reduction of the proteinuria should be considered for treating these patients.