Histiocytosis X is rare and affects children. This disease causes unusually high histiocyte counts. Histiocytes help the immune system fight diseases and foreign bodies. This illness may cause immune cells to form tumors that damage bones and spread to other parts of the body.
Moreover, Histiocytosis X is an autoimmune disease in which immune cells overproduce and attack the body rather than battling infection. Researchers used to think of it as a cancer-like illness. The reason is usually unknown but may often be inherited.