A Case of Secondary Renal Amyloidosis in Children with Juvenile Rheumatoid Arthritis

ABSTRACT

Amyloidosis comprises a diverse group of systemic and local diseases characterized by organ involvement by the extracellular deposition of fibrils composed of subunits of a variety of normal serum proteins. Secondary amyloidosis is caused by the deposition of amyloid A(AA) protein in chronic inflammatory disease. Juvenile rheumatoid arthritis(JRA) has been known to be the most common cause of secondary amyloidosis. We experienced one case of secondary renal amyloidosis in a 12-year-old girl who had suffered from JRA for several years who had visited our renal clinic to evaluate the proteinuria with microscopic hematuria which was detected by chance at school urine screening examination. Apple green birefringence was observed under polarized light with Congo red stain and characteristic electron microscopic findings was also noted in renal tissues which was obtained by percutaneous renal biopsy. In our knowledge, this is the first case report of secondary renal amyloidosis developed in pediatric age in Korea.