PERSISTENT NEPHROTIC SYNDROME : A RENAL BIOPSY STUDY

SUMMARY A survey of renal biopsies of Si patients with the nephrotic syndrome not due to lupus erythematosus, renal amyloidosis, diabetic glomerulosclerosis or one of the congestive renal states shows that there are five main categories. The first category is that of subsiding acute diffuse proliferative glomerulonephritis, which may follow streptococcal sore throat, and in which the prognosis is good. In the second category are patients who develop the nephrotic syndrome after acute diffuse proliferative glomerulonephritis, and who, on renal biopsy, are found to have progressive membrano‐proliferative glomerulonephritis in which there is a steady progression to diffuse glomerular sclerosis and renal failure. The third category is that in which, by light microscopy, there are only minimal glomerular changes. Some patients with continuous nephrotic syndrome in this category have been shown to have no alteration of glomerular structure in periods, between biopsies, of more than six years, while others have developed foci of hyaline sclerosis within a few months. This focal sclerosing glomerulonephritis seemed in most cases to be slowly progressive over a period of years, but in seven fatal cases the course of the disorder was accelerated by the complication of interstitial nephritis, so that renal insufficiency supervened much earlier than could be explained by the glomerular lesions alone. Nine patients whose renal biopsies were initially classified as illustrating the “ minimal lesion ”, subsequently developed focal glomerular sclerosis ; six of these have already died. The fourth category comprises seven other patients who already exhibited focal glomerular sclerosis when first subjected to biopsy ; of these, two have since died. The fifth category is that in which the nephrotic syndrome is due to diffuse membranous glomerulonephritis. None of the patients had an antecedent attack of acute diffuse proliferative glomerulonephritis, and no ætiological or precipitating agent could be incriminated. In no cases has the “ minimal lesion ” ever been demonstrated to have evolved into diffuse membranous glomerulonephritis. Each category of glomerulonephritis has a recognizable pattern, but in many cases this pattern cannot be discerned without the aid of renal biopsy.