source: The Australasian College of Dermatologist summary/abstract:
Amyloidosis is a group of conditions characterised by the deposition of amyloid protein in organ systems. About 18 different types of amyloid protein have been identified.
There are three main types of amyloidosis:
• Primary cutaneous amyloidosis is a condition where amyloid protein is deposited in apparently normal skin without associated deposits in internal organs.
• Primary systemic amyloid may develop as a consequence of an underlying abnormality of the plasma cells in the bone marrow or plasma cell cancer (multiple myeloma). In systemic amyloidosis, the skin is involved along with many other organ systems such as the heart, the nerves, the kidneys and the liver.
• Secondary systemic amyloidosis is seen as a complication of a severe chronic infection such as tuberculosis, or a chronic inflammatory disorder such as rheumatoid arthritis or inflammatory bowel disease. Long-term haemodialysis may be associated with systemic amyloid. In rare cases, it can also be associated with inherited disorders.