Thymoma-associated multiorgan autoimmunity (TAMA) is a severe often fatal disease that presents in some patients with thymoma. It has also been referred to in the medical literature as "thymoma-associated graft-versus-host-like disease".

Presentation

Patients with TAMA present with variable combinations of a

morbilliform The term morbilliform refers to a rash that looks like measles. The rash consists of macular lesions that are red and usually 2–10 mm in diameter but may be confluent in places. A morbilliform rash is a rose-red flat ( macular) or slightly ...

skin eruption, chronic diarrhea, and abnormal liver enzymes. The histopathology of the skin, liver, or bowel mucosa resembles GVHD.

Pathophysiology

Thymoma is a common

neoplasm A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

arising from the

thymus The thymus (: thymuses or thymi) is a specialized primary lymphoid organ of the immune system. Within the thymus, T cells mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. The thymus ...

, the primary lymphoid organ where T cells become educated to distinguish "self" from "non self". In the setting of thymoma, abnormal thymic education occurs as a result of subtle differences in antigen processing. In TAMA these differences result in autoreactive T cells escaping from the thymus. This results in a condition similar to

graft-versus-host disease Graft-versus-host disease (GvHD) is a syndrome, characterized by inflammation in different organs. GvHD is commonly associated with bone marrow transplants and stem cell transplants. White blood cells of the donor's immune system which rema ...

Diagnosis

Treatment

Patients often have a refractory disease course but some patients may respond to phototherapy.

History

This disease name was coined by Emanual Maverakis and described in detail in 2007 but case reports of graft-versus-host-like disease in the setting of thymoma date back to at least the mid 1990s.

References

External links

{{Medical resources , ICD10 = {{ICD10, L, 10.81 Autoimmune diseases