[A case of juvenile rheumatoid arthritis with MPO-ANCA associated nephritis].

A 12-year-old girl with a main complaint of sever pain on the both knees was admitted to our hospital in October, 1995. She gave a three year history of recurrent arthralgia and purpuric rashes, and persistent microhematuria and proteinuria. She developed vesicles and purpuric rashes on the hands and auricles, morning stiffness, fever, uveitis and pericarditis. Laboratory findings showed an elevated level of erythrocyte sedimentation rate and iron-deficiency anemia. Serum perinuclear pattern ANCA with antimyeloperioxidase specificity (MPO-ANCA) was positive. A renal biopsy specimen disclosed a focal and segmental necrotizing glomerulonephritis with crescents. Our case fulfills the both diagnostic criteria for polyarteritis nodosa and juvenile rheumatoid arthritis. This is a rare case of MPO-ANCA associated vasculitis in children.