[Secondary amyloidosis (AA) and renal disease]

Amyloidosis is a disease resulting from extracellular deposition of fibrillar protein in various organs. AA amyloidosis may complicate chronic inflammatory diseases, chronic infections and another chronic diseases. We review 31 patients (13 males and 18 females) with biopsy proven renal or rectal AA amyloidosis, referred to out hospital between january 1999 and november 2002. Renal failure was defined as serum creatinine > or = 1.5 mg/dl. Mean age was 58.4 +/- 15.7 years. The causes of AA amyloidosis were an underlying chronic rheumatologic disease (51.6%), chronic infection (41.9%) and a chronic inflammatory intestinal disorder (6.5%). Renal failure (RF) was detected in 20 patients (61.2%) and proteinuria and hematuria were found in 90.3% and 45.5 respectively. Proteinuria at diagnosis was 5.2 +/- 3.9 g/24 h and mean serum creatinine 3.5 +/- 3.7 mg/dl. Survival of patients without dialysis was 66.8 (51.1% RF, 90.9% non-RF) and 53.4% (38.2 RF, 77.9% non-RF) at 12 and 24 months respectively (p = 0.017). End-stage renal disease developed in 13 patients (41.9%). Ten patients were maintained on hemodialysis and 3 on CAD. Survival in dialysis at 6 and 12 months was 68.3% and 42.7% respectively. Fifteen patients died and the main causes of death were: infections (46.6) haemorrhagic complications (33.3%), cardiovascular events (13.3%) and cachexia (6.6%).