Alpha-heavy chain disease is a rare form of amyloidosis, a condition in which abnormal proteins called amyloid fibrils accumulate in the body's organs and tissues. Alpha-heavy chain disease is caused by the accumulation of abnormal proteins called immunoglobulin alpha-heavy chains in the body's organs and tissues. These proteins can cause organ damage and lead to organ failure. Symptoms of alpha-heavy chain disease include fatigue, weight loss, anemia, and swelling of the legs and abdomen. Treatment for alpha-heavy chain disease typically involves chemotherapy and/or stem cell transplantation.