OBJECTIVETo investigate the clinicopathological feature and treatment of idiopathic membranous nephropathy (IMN) in children.

METHODA retrospective analysis of 25 cases of biopsy-proven IMN seen between January 2004 and December 2009.

RESULTThe incidence of IMN was 3.81% in all the children patients who underwent renal biopsy. Of 25 patients with IMN, nine were boys and sixteen were girls. The mean age at onset was (9.4 ± 3.4) years with a range of 2 - 14 years. Renal biopsies were performed at a median 2.5 months (range 0.4 - 11 months) after onset. The clinical manifestations included nephrotic syndrome (NS) nephritic type in 21 cases (84%) and glomerulonephritis in 4 cases. All patients presented with hematuria, and 7 had macroscopic hematuria. Hypertension was noted in 4 patients. Two patients were complicated with thrombosis. One patient was in a chronic renal insufficiency(CRI)state. According to the MN staging criteria, 21 cases were in stage II IMN (84%). Six patients showed moderate or severe tubulointerstitial lesion. Focal segmental glomerulosclerosis (FSGS) was found in two patients. Of the 22 patients with NS and nephrotic proteinuria, 21 cases were treated with prednisone initially and in 20 of them the efficacy of corticosteroid therapy was evaluated:one of them was steroid sensitive (became steroid-resistant after relapse) and all the others were steroid-resistant (95%). The subsequent treatment: eight of them were treated with prednisone followed by a taper to alternate-day therapy. Five of them had complete remission and three partial remission. Twelve cases were treated with combined therapy of prednisone and immunosuppressive agents. Of these 12 cases together with one case who received initially combined treatment with prednisone and immunosuppressive agent and one case treated with prednisone initially for five weeks then with combined therapy contained another immunosuppressive agent, totally 14 cases, 5 had complete remission, 2 partial remission, 3 did not achieve remission, and 3 had unknown response.

CONCLUSIONOf the patient cohort, the predominant presenting feature was nephrotic syndrome, and with different degree hematuria. Almost all of them were steroid resistant, but followed by a taper to alternate-day therapy, some could achieve remission. The effect of a combination of prednisone and immunosuppressive agent is needed to be further proven in children.