Clujul Medical - Iuliu Haţieganu

Cazuri clinice
ACUTE MEGAKARYOCYTIC LEUKEMIA AND
MYELOFIBROSIS. CONSIDERATIONS BASED ON A
CASE REPORT
ALIZ HORÁK 1 , R. BUIGA 2 , OLGA ŞORIŢĂU 2 , ŞTEFANIA NEAMŢU 2 ,
M. CUCUIANU 1
1 Synevo Laboratories
2 Oncological Institute „I. Chiricuţă” Cluj-Napoca
Summary
The case of a girl aged 2.4 years with pulmonary stenosis and atrial septal
defect who developed an acute megakaryocytic leukemia associated with myelofibrosis,
ocular complications related to thrombo- haemorrhagic phenomena. and lethal
outcome is presented. The pathogenesis of myelofibrosis and the role played by cellular
factor XIII subunit A are discussed.
Key words: megakaryoblastic leukemia, myelofibrosis, thrombohemorrhagic
phenomena
Patients with pancytopenia, low percentage of blast cells and intense
myelofibrosis were reported in 1963 by Lewis and Szur, this pathologic condition being
designated as malignant myelofibrosis (1). Later on, a megakaryocytic phenotype was
detected in the bone marrow cells of many such patients, and it was considered that
myelofibrosis would occur secondarily to an acute megakaryocytic (or
megakaryoblastic) leukemia (2). As myelofibrosis was found to occur in other cases of
acute leukemia, especially myelomonocytic or myelomonoblastic forms, it was stated
that probably megakaryocytic leukemia does not exist, this name being only used to
describe the participation of megakaryocytes in a leukemic process (3). It was only 1985
that acute megakaryocytic leukemia was admitted as a nosologic entity, being included
in the FAB classification as AML M7 (4).
This malignant condition is rather seldom diagnosed, as the megakaryoblasts
and promegakaryocytes can hardly be identified by light microscopy and polychrome
staining, being easily confused with ALL. Suspicion can be engendered by peroxidase
negative blasts with budding cytoplasm, especially if marrow is aspirated with difficulty
because of intense myelofibrosis (4).
Our laboratory has recently detected such a case with ocular complications in
the context of thrombo-haemorrhagic phenomena and lethal outcome.
The girl OE aged 2.4 years had been sent by Pediatric Clinic N o I with the
diagnosis of acute leukemia at onset. She was admitted at the Department of Pediatric
Oncology on March 28, 2006. The child also displayed a congenital heart disease,
namely pulmonary stenosis and atrioseptal defect. She was underweight and presented a
dysmorphic dentition. On admission she was in poor condition with fever 38.8 o C,
pallor, weakness, bruising and pharingoamygdalian congestion. A distended abdomen
displaying collateral circulation, hepatosplenomegally (confirmed by ultrasound) as
well as a generalized lymphadenopathy were detected. Precordial systolic murmur
grade III.
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