A study of membranoproliferative glomerulonephritis in Iran.

BACKGROUND: The aim of this study was to review the morphologic patterns of membranoproliferative glomerulonephritis (MPGN) in 100 Iranian patients using light microscopy (LM) and electron microscopy (EM), and to compare the treatment and outcome in 13 patients with two biopsies.

PATIENTS AND METHODS: A retrospective study of 713 kidney biopsies of Iranian patients received between 1981 to 1994 was carried out. Of the 713 kidney biopsies, MPGN (n=106) and membranous glomerulopathy (n=112) made up the highest numbers of cases.

RESULTS: Among 100 MPGN patients, 55 (55%) were MPGN type I, 10 were type II (10%), and 35 type III (35%). Eighty-three (83%) had nephrotic proteinuria, 39 (39%) had hematuria, and 52 (52%) were hypertensive. Complement levels were estimated in 58, with low C3 in 10. The glomerular involvement was irregular, with focal hypercellularity in 47 patients (47%), widely patent capillaries in 50 (50%), arteriosclerosis in 48 (48%), and with hyaline change in 25 (25%). Follow-up data (22-130 months) was available in 61 (61%) patients: 6 (10%) died after 14-56 months, 27 (44%) were on maintenance hemodialysis for 15-110 months, and three received transplants. Thirteen patients had detailed follow-up and a second biopsy after 24-120 months. All 13 presented with edema and nephrotic range proteinuria, with hematuria and hypertension in five and azotemia in four. Seven of the 13 patients received initial steroids, followed by antiplatelet or antihypertensive drugs. Four (type III) patients received antiplatelet and antihypertension drugs, and two (type III) received only antihypertensive drugs. In the first biopsy, glomerular changes by light microscopy were non-uniform in 7 of 10 (70%) type III MPGN cases. Vascular changes were absent or mild in 11, and moderate in two. In the second biopsies, 10 showed decrease in cellularity, with many open capillaries, persistence of deposits by EM in all, and progression of vascular sclerosis in eight, and tubulointerstitial changes in 10. Among the 13, six were clinically stable, another six received dialysis followed by transplant in three, and one had relapses with episodes of cryoglobulinemia. Three patients died.

CONCLUSION: There is a high incidence of MPGN in Iranian patients, with a substantial number of type III MPGN cases. Second biopsies showed decreased cellularity, but increase in chronic tubulointerstitial and vascular cases. Steroids did not appear to benefit the outcome in types I and III MPGN patients compared to patients who received antihypertensive and antiplatelet treatment without steroids.