Glomerular basement membrane antigens in congenital and acquired nephrotic syndrome in childhood.

Urinary and serum glomerular basement membrane (GBM) antigens were detected by immunodiffusion in patients with nephrotic syndrome and in healthy subjects. The excretion of urinary GBM antigens was greatest in patients with congenital nephrotic syndrome of Finnish type (CNF) and in patients with acquired, therapy-resistant nephrotic syndrome who had a variety of histologically identified glomerular lesions. One GBM antigen, indistinguishable from the urinary one, was also detected in the serum of four of these patients. Excretion of urinary GBM antigens was within normal limits, in patients with steroid-sensitive nephrotic syndrome with minimal changes in renal histology and in the parents (heterozygotes) of CNF patients.