During the past three years we have had the opportunity of studying about sixty cases of kidney disease in children. According to the clinical findings these cases seem to have fallen into four groups. By means of laboratory data we have endeavored to strengthen this classification so as to make it useful from a diagnostic and therapeutic standpoint:
Group I comprises cases which began either without apparent cause, in children seemingly in perfect health, or in which the mother had, perhaps, noticed that the child was pale. There was little or no elevation of temperature and apparently no accompanying disease. Edema of the face or legs first appeared. It spread rapidly to the remainder of the body. The edema was very persistent, or if it did disappear it showed a decided tendency to recur. There was no hematuria but the urine, at times, was diminished in quantity and always contained