The nephrotic syndrome is a distinct abnormal clinical and biochemical entity characterized by edema, massive proteinuria, hypoalbuminemia and hypoproteinemia, and hyperlipemia and hypercholesterolemia. Hematuria, hypertension, or azotemia may or may not be present. The basic cause is unknown, but it probably represents an antigenic response to a number of known and unknown stimuli in susceptible persons. The syndrome may accompany many forms of renal and other pathology which are listed in Table 1.
In most studies discussed in this review, nephrotic syndrome due to intrinsic renal disease is considered. Membraneous glomerulonephritis is the commonest lesion encountered pathologically, at least in the adult.1 Thickening of the glomerular capiilary tuft basement membrane is observed by light microscopy as the principal renal lesion. On the basis of light microscopy, "lipoid nephrosis"—a form more commonly described in children—was thought to exhibit only tubular degenerative abnormalities with minimal or no glomerular lesions. However, electron microscopy