Down Syndrome with Myelodysplasia of Megakaryoblastic Lineage

Ric Henderson; Libby Spence

doi:10.29074/ascls.19.3.161

This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.

Ric Henderson, BS CLS(NCA)
Libby Spence, PhD CLS(NCA)⇑

are of the Department of Clinical Laboratory Sciences, School of Health Related Professions, University of Mississippi Medical Center, Jackson MS

Address for correspondence: Libby Spence PhD CLS(NCA), Professor, Department of Clinical Laboratory Sciences, School of Health Related Professions, University of Mississippi Medical Center, 2500 North State Street, Jackson MS 39216. (610) 984-6329, (601) 815-1717 (fax). Lspence{at}shrp.umsmed.edu

Extract

The association between Down syndrome and acute myelogenous leukemia (AML) has been well documented.^1,2,3 AML in Down syndrome is usually a specific type of megakaryoblastic leukemia (M7, AMKL).¹ A myelodysplastic syndrome generally precedes this malignancy. Down syndrome patients with AMKL have a much better prognosis than other children with AML.⁵

A case study of a 22-month-old female with Down syndrome and myelodysplastic syndrome of a megakaryoblastic lineage is presented here. Upon admission to a pediatric hematology/oncology clinic, flow cytometry results reported a distinct population of phenotypically abnormal myeloblasts expressing myeloid antigens and the immature cell markers.

The patient was placed on a national research group study and began chemotherapy treatment. To date she has received two courses of cytarabine (ara-c) and daunorubicin therapy, which were tolerated well, and is awaiting her third course. Her blood counts stabilize for a while after treatments and her prognosis is good.

The association between Down syndrome and AML has been well documented for nearly 70 years.^1,2,3 Children with Down syndrome have a tenfold to 20-fold increased risk of developing AML over those who do not carry the extra chromosome 21.² It is estimated that about two percent of children presenting with pediatric leukemia have Down syndrome.⁴ AML in Down syndrome is usually a specific type of acute megakaryoblastic leukemia (M7, AMKL).¹ AMKL is very rare in the general population. A myelodysplastic syndrome generally precedes this malignancy. Myelodysplastic syndrome is a disease in which the bone marrow does not function normally and is sometimes referred…

ABBREVATIONS: AMKL = acute megakaryoblastic leukemia; AML = acute myelogenous leukemia; BMT= bone marrow transplant; CBC = complete blood count; CMV = cytomegalovirus; RSV = respiratory syncytial virus; TAM = transient abnormal myelopoiesis.