LEUKEMIA MEGAKARIOBLASTIK AKUT PADA SEORANG ANAK

Abstract

Acute Megakaryoblastic Leukemia (FAB AML M7) occurs in all age groups with two peaks in distribution. The one is in adults and the
other in children 1 to 3 years of age especially in those with Down's syndrome. The diagnosis of AML M7 requires more than 30% of the
nucleated bone marrow cells being megakaryoblasts. The AML M7 was under diagnosed before the availability of monoclonal antibodies.
The more common types of AML MO-M6 have to be excluded by morphological and cytochemical analysis whereas immunology is needed
to exclude ALL. The megakaryocytic nature of the leukemia has to be proven by ultrastructural demonstration of platelet peroxidase or by
immunological demonstration of CD61, CD42, CD41 on the surface of the leukemic blasts. Megakaryocytic/megakaryoblastic leukemias
show a wide morphologic spectrum. Cytoplasmic blebs and protrusions are the most prominent feature of many cases. The nuclei of
these cells are round with more finely reticulated chromatin and with prominent nucleoli. The megakaryoblastic nature of these cells can
be suggested by morphology. Cytochemistry is of limited diagnostic value in megakaryoblastic leukemias. Usually it is used to exclude
the more common types of leukemia. An eighteen months girl was admitted to hospital with anemia and hepatosplenomegaly. There is
dismorphic - hypertelorism face and enlargement of neck lymph nodes. The laboratory examination found anemia, hyperleukocytosis with
75 % blast cells. Morphologically the blast cells show prominent blebs and cytoplasmic budding resemble features of budding platelets.
The cytochemistry staining for granulocyte and erythrocyte lineages were negative. The expressions of lymphoid and myeloid lineages
markers by immunoflowcytometry method were also negative. Cytogenetic examination was followed. The physical and laboratory
examination result conclude a child with Acute Megakaryoblastic Leukemia. Cytogenetic examination was followed