Prospective study on renal outcome of IgA nephropathy superimposed on diabetic glomerulosclerosis in type 2 diabetic patients

Background and methods. In order to examine the clinical outcome of IgA nep hropathy (IgAN) superimposed on diabetic glomerulosclerosis in type 3 patie nts we studied 36 Chinese patients (26 men, 10 women), who were recruited f or renal biopsy when they had proteinuria of more than 1 g/day. Twenty-seve n had isolated diabetic glomerulosclerosis and nine had IgAN superimposed o n diabetic glomerulosclerosis (combined). Renal function was assessed by se rial serum creatinine, 24-h urine protein and creatinine measurements. Pati ent survival rate, incidence of end-stage renal disease (ESRD), blood press ure, and glycaemic control status were determined. Results. The age at the time of renal biopsy was younger for the combined g roup when compared with the diabetic glomerulosclerosis group (44 +/- 3.6 v s 58 +/- 2.1 years, P = 0.006). The duration of diabetes was, however, simi lar for the two groups (8.0 +/- 2.3 vs 6.7 +/- 1.2 years, P = NS). After a mean follow-up of 31.6 +/- 15.3 months, 15 patients tone in the combined gr oup and 14 in the diabetic glomerulosclerosis group) developed ESRD. Nine p atients tall in the diabetic glomerulosclerosis group) died during follow-u p, With similar glycaemic and blood pressure control, the two groups had co mparable rate of decline of creatinine clearance (CrCl) (-0.73 +/- 0.26 vs -0.73 +/- 0.18 ml/min.1.73 m(2)/ month. P=NS), final serum creatinine (363/-134 vs 426 +/- 52 mu mol/l. P=NS) and proteinuria levels (4.3 ++/- 0.9 vs 4.4+/-0.6 g/day, P=NS), as well as CrCl (44.1 +/- 19.0 vs 33.4 +/- 6.9 ml/ min/ 1.73 m(2), P=NS). Conclusion. It is concluded that the superimposed IgAN does not significant ly alter the medium-term clinical outcome of patients with diabetic glomeru losclerosis.