Acute megakaryoblastic leukemia in Down syndrome: Orbital infiltration

PURPOSE: To describe an uncommon ocular presentation of acute megakaryoblas tic leukemia in a child with Down syndrome. METHOD: Case report. Initial manifestation of disease was bilateral proptos is with secondary exposure keratitis caused by leukemic infiltration of the orbits. RESULTS: Bone marrow biopsy and immunophenotyping established the diagnosis of acute megakaryoblastic leukemia (FAB-MT). The leukemia was treated succ essfully with chemotherapy, with resolution of proptosis. The patient remai ned in remission more than 1 year after cessation of treatment. CONCLUSIONS: Bilateral proptosis can be a presenting sign of acute megakary oblastic leukemia, a malignancy associated with Down syndrome. (C) 2000 by Elsevier Science Inc. All rights reserved.