Diarrhea, nephrotic syndrome and hidradenitis suppurativa: an unusual case.

In contrast to AL amyloidosis, where clonal plasma cells in bone marrow produce immunoglobulins that are amyloidogenic, and familial amyloidoses in which a mutant protein forms amyloid fibrils, the incidence of AA amyloidoses has been reduced since the treatment of infectious diseases and rheumatoid arthritis improved. AA amyloidoses are due to amyloid formed from serum amyloid A, an acute phase protein produced in response to inflammation. With the reduction of chronic infectious diseases such as tuberculosis or osteomyelitis from the western hemisphere, AA amyloidosis is rarely seen; however, it still occurs in patients with rheumatoid arthritis, inflammatory bowel disease or untreated Mediterranean fever. We report an unusual case of chronic hidradenitis suppurativa leading to AA amyloidosis.