AA amyloidosis: Mount Sinai experience, 1997-2012.

Area of Science:

• Nephrology
• Rheumatology
• Genetics

Background:

• AA amyloidosis involves serum amyloid A protein deposition, often linked to chronic inflammation like rheumatoid arthritis or Crohn's disease.
• An increasing number of patients present with idiopathic AA amyloidosis, lacking a clear inflammatory stimulus.
• The disease primarily affects organs, with renal involvement being particularly common.

Purpose of the Study:

• To review patients with AA amyloidosis at Mount Sinai from 1997-2012.
• To analyze underlying diseases, organ involvement, inflammatory markers, and pyrin gene mutations.
• To evaluate patient outcomes and identify potential therapeutic targets.

Main Methods:

• Retrospective chart review of 43 AA amyloidosis patients.
• Analysis of underlying conditions, organ involvement (especially renal), inflammatory markers (cytokines), and pyrin gene mutations.
• Assessment of patient outcomes including dialysis and transplantation rates.

Main Results:

• Rheumatoid arthritis (21%) and Crohn's disease (16%) were common causes, with 21% having idiopathic AA amyloidosis.
• Renal involvement was observed in 95% of patients; 44% required dialysis, and 12% received transplants.
• Interleukin-6 was the only consistently elevated cytokine, and three patients (33%) had the E148Q pyrin gene mutation.

Conclusions:

• The study confirms a rise in idiopathic AA amyloidosis, suggesting potential genetic factors.
• Renal disease remains a primary complication of AA amyloidosis.
• Elevated interleukin-6 levels present a potential therapeutic target for managing AA amyloidosis.