[Thrombocytopenia with absence of the radius in a 24-year-old woman].

Thrombocytopenia with absent radius syndrome (TAR) is a rare disorder appearing at birth or soon after. The heredity pattern is autosomal recessive, although some patients in successive generations have been reported. A 24 year-old woman is presented who had moderate thrombocytopenia and shortened forearms due to lack of radius, with preserved thumbs. Her peripheral blood was normal but for a decreased platelet count. The bone marrow megakaryocytes were decreased as well. No other relatives were affected. The association of thrombocytopenia and bilateral radius aplasia, along with the differential diagnosis, are commented, stress being laid on the fact that the patient was diagnosed in adulthood.