Thymectomy

A thymectomy is an operation to remove the thymus gland. It usually results in remission of myasthenia gravis with the help of medication including steroids. However, this remission may not be permanent.

A thymectomy is mainly carried out in an adult. This is because the thymus loses most of its functional capacity after adolescence, but does retain a small portion of its function during adulthood. This is shown in the decreasing size of the thymus with increasing age after adolescence.

The role of the thymus prior to adolescence is to educate T-cells to a specific response where they then populate the lymphoid organs, for storage until needed. Removal of the thymus as an adult has little immediate effect on the immune system as its role has been completed.

Thymic hypoplasia as may be seen in DiGeorge Syndrome results in no T-cell education, and therefore a severe compromise in T cell mediated and humoral responses.