Congenital athymia

Rare immune disorder where the thymus is missing at birth

Congenital athymia is an extremely rare disorder marked by the absence of the thymus at birth. T cell maturation and selection depend on the thymus, and newborns born without a thymus experience severe immunodeficiency. A significant T cell deficiency, recurrent infections, susceptibility to opportunistic infections, and a tendency to develop autologous graft-versus-host disease (GVHD) or, in the case of complete DiGeorge syndrome, a "atypical" phenotype are characteristics of congenital athymia.

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