Acute glomerulonephritis in children. An evolutive morphologic and immunologic study of the glomerular inflammation.

This study deals with 80 children showing a clinically typical acute nephritic syndrome with proteinuria and/or hematuria, edema, and hypertension. Their ages ranged between 2 years 5 months and 16 years; 36 cases were female. In 73 cases a streptococcal infection was demonstrated; the remaining 7 cases did not show morphologic differences with the former. No previous renal disease nor familial history of nephropathies were elicited. In every case a renal biopsy was obtained in the first 60 days of clinical disease; in 46 cases a second renal biopsy was obtained sometime between 6 and 45 months since the beginning of the disease. In 3 cases the renal tissue was considered to be normal by light microscopy, immunofluorescence and electron microscopy in both the first and second biopsies. These 3 patients were not considered as cases of morphologic acute glomerulonephritis in spite of showing a typical clinical picture and they are not included in the evaluation of the glomerular inflammatory evolution. In all the remaining 77 cases C3 granular and segmentary intramembranous and mesangial dense deposits were found in the first biopsy. The second biopsy showed morphologic and immunologic normalization in 27% of the cases, slight lesions in 56% and an increase in severity in 17% of the cases.