ABSTRACT
Thrombocytopenia is the most common hemostatic disease of the newborn. Inherited giant platelet syndromes are a heterogeneous group of rare bleeding disorders. In this paper we describe here a female neonate with autosomal dominant hereditary macrothrombocytopenia. A female neonate was referred to our center due to mucosal hemorrhage [nasal and gastrointestinal bleeding]. Her mother's platelet count was normal. However her father, paternal uncle and two paternal aunts also had severe thrombocytopenia and all of them underwent splenectomy for idiopathic thrombocytopenic purpura [ITP]. Considering all clinical and laboratory findings, autosomal dominant hereditary macrothrombocytopenia was the best diagnosis. It is important to differentiate between congenital and acquired thrombocytopenia to avoid unneeded and potentially harmful therapy. Treatment is not usually necessary, however some patients with hereditary thrombocytopenia may benefit from bone marrow transplantation