We report here a case of type 1 mesangiocapiUary glomerulonephritis as well as a case of mesangial proliferative glomerulonephritis associated with streptococcal skin infection superimposed on atopic dermatitis. Both were endemic occurrences of postinfectious glomerulonephritis developed after repeated dirty-skin treatments for atopic dermatitis performed by unauthorized individuals under unsanitary conditions. Of 20 patients who were similarly treated and subsequently admitted to our hospital because of skin infection and fever, 8 (40%) showed urinary abnormalities. Four patients had renal dysfunction with acute nephritic onset. Almost all showed a decrease in CH50 values and an increase in levels of antistreptolysin·and IgE. In the 2 cases presented here, the disease eventually regressed in association with improvement of the skin infection. Although the occurrence of postinfectious glomerulonephritis has recently become uncommon, we must take care to note urinary abnormalities as early as possible in order to prevent the progression of glomerulonephritis.