Thrombocytopenia with absent radii (the TAR syndrome).

The congenital association of thrombocytopenia and absent radii has been designated the TAR syndrome. This article describes a female with the TAR syndrome who presented with the first known onset of hemorrhagic phenomenon at the age of 47, the oldest age of onset described in the literature. The incidence, clinical manifestations, differential diagnosis, course, and effects of treatment of the syndrome are reviewed, and proposed etiologic factors are discussed.