Renal biopsy diagnosis in children presenting with haematuria

We reviewed the clinical and renal biopsy findings in 322 children presenting during the years 1975-1996 with recurrent macro- or continuous microscopic haematuria persisting for > or =6 months, in whom non-glomerular causes were excluded. Family involvement was documented for first-degree relatives. All biopsies were examined by light microscopy, 317 by electron microscopy and 315 by immunofluorescence. Biopsies were classified as IgA nephropathy (78), Alport nephropathy (86), thin basement membrane nephropathy (TMN) (50), miscellaneous glomerulonephritis (32), hilar vasculopathy (28) and normal glomeruli (48). Although microscopic haematuria alone was more frequent in Alport nephropathy and TMN, the pattern of haematuria in individual patients did not predict histology. Of patients with familial haematuria, 79% of biopsies showed either Alport nephropathy or TMN. Hilar vasculopathy was observed both in isolation and in all abnormal histological categories.