An unusual cause of renal amyloidosis secondary to gout: the first description of familial occurrence.

BACKGROUND

AA amyloidosis caused by the chronic inflammation accompanying gouty arthritis is extremely rare and familial occurrence has not been described so far.

CASE REPORT

We present the case of two brothers (47 and 44 years old) with 7- and 10-year history of hyperuricaemia and chronic tophaceous gout with polyarticular involvement. The enzymatic assay performed in their erythrocytes proved the partial hypoxanthine-guanine phosphoribosyl transferase deficiency (Kelley-Seegmiller syndrome), the genetic defect of purine metabolism. Later on they developed proteinuria and chronic renal insufficiency /CRI/. Renal biopsy disclosed the combination of AA amyloidosis and gouty nephropathy in both the cases. Despite the standard treatment the older brother progressed to chronic renal failure. On the contrary, the younger one being longterm treated with oral colchicin have stabilized CRI.

CONCLUSIONS

Only several cases of AA renal amyloidosis until recently, secondary to gout have been reported. Our case represents the first report of familial occurrence of this extremely rare disease.