[Effect of plasma exchange therapy on IgA nephropathy in children--a retrospective study].

Clinical and pathological analyses were performed to evaluate plasma exchange therapy (PEx) in children with severe IgA nephropathy. Values for PEx were obtained in 17 cases (male 13, female 4, 12.2 +/- 4.3 [M +/- SE] years old), whose proteinuria and creatinine clearance (Ccr) were 4.6 +/- 1.8 g/day and 64.4 +/- 31.3 ml/min/1.73 m2, respectively, immediately prior to treatment. Values for proteinuria in children after PEx were significantly higher than those of 151 cases of IgA nephropathy who were not treated by PEx in our unit. Ccr in patients who underwent PEx significantly improved during the first 6 months, whereas serum IgG, IgA and C3 levels returned to pre-PEx levels following a transient reduction at one month. Fourteen out of 17 cases were followed for more than 2 years. Among these patients, 8 (57.1%) progressed to chronic renal failure (CRF, Ccr < 30 ml/min/1.73 m2), and 6 showed improvement in Ccr (non-CRF, Ccr > or = 30 ml/min/1.73 m2). In 4 of these cases, PEx was introduced at an acute clinical phase of glomerulonephritis. Compared to 8 patients with progression (CRF), initial renal histology in these 6 patients revealed a lower percentile of glomerular sclerosis index (GSI) and had a significantly higher percentile of cellular crescents. These results suggest that: 1) PEx is not an adequate method of treatment of IgA nephropathy with advanced glomerulosclerosis, 2) PEx is effective in the acute stage of IgA nephropathy.