[Chediak-Higashi syndrome. A laboratory finding].

The Chediak Higashi Syndrome (CHS) is an inherited autosomic recessive immunodeficiency rarely reported. Two pediatric cases are presented, where the first approach to diagnosis was the laboratory report of giant granulation in granulocytes and lymphocytes, observed in peripheral blood smear. In order to confirm the diagnosis of CHS, immunologic tests, skin biopsy, bone marrow aspirate and microscopic hair examination were performed. It is remarked the importance of the careful examination of the blood smear in the detection of this cases, whereas clinic manifestations are not relevant until the hematologic suspicious of the syndrome is evident. The early detection of these patients can lead to bone marrow transplant, which is the only curative treatment to this disorder, lethal in the first decade of life.