Thymoma-associated multiorgan autoimmunity (TAMA) is a severe often fatal disease that presents in some patients with

thymoma A thymoma is a tumor originating from the epithelial cells of the thymus that is considered a rare malignancy. Thymomas are frequently associated with neuromuscular disorders such as myasthenia gravis; thymoma is found in 20% of patients with mya ...

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

Pathophysiology

Thymoma A thymoma is a tumor originating from the epithelial cells of the thymus that is considered a rare malignancy. Thymomas are frequently associated with neuromuscular disorders such as myasthenia gravis; thymoma is found in 20% of patients with mya ...

is a common neoplasm arising from the

thymus The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or ''T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. ...

, 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 remain wit ...

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 Emanual Maverakis is an American physician-scientist, immunologist working in the field of immunogenetics, and a professor at the University of California, Davis. Early life and education Emanual Maverakis was born in Oakland, California, and sp ...

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