RESUMO
Em 100 crianças portadoras de glomerulonefrite aguda pós-infecciosa (GNAPI) foram analisados os níveis séricos de C3, C4 e CH50. Durante as primeiras quatro semanas de evoluçäo demonstraram-se níveis séricos inferiores ao normal em todas as 97 determinaçöes de C3 (X =34,8 + ou - 13,2 mg/dl 0 - 2 semanas e 48,2 + ou - 18,2 mg/dl 2 - 4 semanas) e em 38 de 98 determinaçöes de C4 (X = 24,3 + ou - 11,6 mg/dl 0 - 2 semanas e 30,1 + ou - 12,5 mg/dl 2 - 4 semanas). A maioria das determinaçöes realizadas pós quatro semanas de evoluçäo demonstrou níveis séricos normais de C3, C4 e CH50. Houve predomínio da via alternativa (60%) em relaçäo à clássica (40%), independente do sexo e foco infeccioso. Os autores discutem a ativaçäo do sistema complemento em GNAPI
Assuntos
Pré-Escolar , Criança , Humanos , Masculino , Feminino , Ativação do Complemento , Glomerulonefrite/sangue , Fator Nefrítico do Complemento 3/análise , Complemento C4/análiseRESUMO
A 7-year-old boy with mild renal failure and signs and symptoms of acute poststreptococcal glomerulonephritis including severe hypocomplementemia had, by renal biopsy, numerous crescents but no deposits in the glomerular capillary loops. Instead, deposits identical in location and composition to those described for children with idiopathic rapidly progressive glomerulonephritis were present. The severe hypocomplementemia was found to be due to high levels of C3 nephritic factor; niether nephritic factor nor hypocomplementemia has been reported in rapidly progressive glomerulonephritis of the idiopathic type. Following prompt therapy with methylprednisolone intravenously, serologic abnormalities disappeared and renal function greatly improved, but a later biopsy showed 50% of the glomeruli obliterated by scarring. The case is of importance not only in indicating that severe hypocomplementemia does not rule out idiopathic rapidly progressive glomerulonephritis but also in adding to the list of diseases in which nephritic factor can be found.