RESUMO
PURPOSE: The long term disease course and prognostic factors were evaluated in childhood Henoch-Schonlein purpura nephritis(HSPN). METHODS: A total of 75 children(44 boys and 31 girls) with HSPN were included in this study. The onset age was 8.0+/-3.1 years(2.3-15.3 years), and the follow-up period was 4.3+/-3.6 years(1.0-17.1 years). Kidney biopsy was done in 24 children(32%). Initial clinical and laboratory findings were evaluated. In addition, polymorphisms of the renin angiotensin system(RAS) genes(insertion/deletion in intron 16 of ACE gene, M235T in AGT gene, and A1166C in AGTR gene) were analysed. The initial and last clinical states were classified into 4 groups as follows:A, normal; B, minor urinary abnormalities; C, active renal disease (nephrotic-range proteinuria and/or hypertension with serum creatinine < or =1.5 mg/dL); D, renal insufficiency. RESULTS: At the onset, the clinical states of the patients were B in 26(35%), C in 46(61%), and D, in 3(4%). The distribution of the RAS gene polymorphism of HSPN were not different from that of 100 healthy control subjects. At the last follow-up, the clinical states of the patients were A in 23(31%), B in 38(50%), C in 9(12%), and D in 5(7%). A multiple logistic regression identified age at the onset and initial urine protein excretion as significant prognostic factors. Analysis of genotypes of the 3 RAS genes as prognostic values revealed no statistical significance. CONCLUSION: Older age at onset and severe proteinuria were identified as poor prognostic factors of childhood HSPN. Implication of the RAS gene polymorphism in HSPN could not be validated in this small-scale retrospective study.