Amyloid-associated protein (AA)-type systemic amyloidosis has been referred to as secondary amyloidosis because it is secondary to an associated inflammatory condition.
The secondary amyloidoses are due to amyloid formed from serum amyloid A (SAA), an acute-phase protein produced in response to inflammation.
There are several SAA proteins, and in humans, AA amyloid deposits consist of fragments of at least five different molecular forms.
With the virtual abolition of chronic infectious diseases such as tuberculosis, osteomyelitis, and bronchiectasis from the Western Hemisphere, AA amyloidosis is rarely seen. However, it still occurs in patients with rheumatoid arthritis, inflammatory bowel disease, and untreated familial Mediterranean fever (FMF).
Associations
inflammatory conditions
tumors
- non-Hodgkin lymphomas
References
Lachmann, H. J., Goodman, H. J.B., Gilbertson, J. A., Gallimore, J. R., Sabin, C. A., Gillmore, J. D., Hawkins, P. N. (2007). Natural History and Outcome in Systemic AA Amyloidosis. NEJM 356: 2361-2371