Familial glomerulopathy with proximal tubular dysfunction: a new syndrome?

Two female siblings with nephrotic syndrome and proximal tubular dysfunction are described. One, aged 15 months, presented with steroid-resistant nephrotic syndrome and was found to have partial Fanconi syndrome and hypothyroidism. At the age of 21 months her renal function started deteriorating rapidly and she died of septicaemia 5 months later. The second sibling, aged 3 years, had steroid-resistant nephrotic syndrome with proximal renal tubular acidosis and hyperaminoaciduria. The renal biopsies in both showed unusual changes in glomerular basement membrane along with IgM and C3 deposition. It is suggested that these siblings may be suffering from a hitherto undescribed clinico-pathological entity.