Antineutrophil cytoplasmic autoantibody-associated glomerulonephritis in children

Aretrospective investigation was conducted by members of the Japanese Society for Pediatric Nephrology from 1990 to 1997 to define the clinical features and outcome of antineutrophil cytoplasmic autoantibody (ANCA)-associated glomerulonephritis in children. Thirty-four ANCA-seropositive Japanese pediatric patients with biopsy-proven pauci-immune necrotizing crescentic glomerulonephritis were identified. Of these, 3 cases associated with Wegener's granulomatosis were excluded because of the small sample size. Among the 31 patients studied, 10 had a diagnosis of necrotizing crescentic glomerulonephritis alone and 21 had microscopic polyangiitis. Females predominated (87%), and the median age at onset was 12 yr. Twenty-six patients received treatment with cyclophosphamide and corticosteroids, and five patients received treatment with corticosteroids alone; 84% of patients achieved remission, and 39% of responders relapsed in a median of 24 mo. ANCA titers correlated with response to treatment and disease activity, with some exceptions. Patients were followed for a median of 42 mo (range, 3 to 96 mo). Nine of 31 patients (29.0%) progressed to end-stage renal disease, 6 (19.4%) had reduced renal function, and 15 (48.4%) had normal renal function at the last observation. One patient (3.2%) died from cytomegalovirus infection 3 mo after initiation of therapy. Life-table analysis showed 75% renal survival at 39 mo. Patients who subsequently developed end-stage renal disease (n = 9) had significantly higher average peak serum creatinine levels and more chronic pathologic lesions at diagnosis compared with patients with favorable renal outcome (n = 15). In conclusion, our clinical experience suggests that the clinical disease spectrum of ANCA-associated glomerulonephritis is similar in pediatric and adult patients, but there is a female predominance in children.