myelodysplasia

Question 1

definition of myelodysplasia

Answer 1

A series of haematologic conditions characterized by chronic cytopaenia (anaemia, neutropaenia, thrombocytopaenia) and abnormal cellular maturation.

ineffective haematopoiesis

with risk of life threatening infarction and bleeding

30% transform to acute leukaemia

Question 2

subgroups of myelodysplasia and percentage of blasts in the marrow

Answer 2

refractory anaemia (RA) <5%

RA with ringed sideroblasts (RARS) <5% (>15% RS)

RA with excess blasts (RAEB) 5-20%

chronic myelomonocytic leukaemia (CMML) - up to 20% plus peripheral blood monocyte count >1x10(9)/L

RAEB in transformation (RAEB-t) 21-30%

Question 3

aetiology of myelodysplasia

Answer 3

primary, or people had chemo or radiotherapy

may have chromosomal abnormalities –deletions (e.g. partial or total loss of chromosomes 5, 7, 20 or Y), monosomy 7, trisomy 8 or complex karyotypes with multiple abnormalities.

Question 4

RF for myelodysplasia

Answer 4

chemo

radio

occupational exposure to toxic chemicals

Question 5

epidemiology of myelodysplasia

Answer 5

65-75yrs

more common in males

twice as common as AML

Question 6

Sx of myelodysplasia

Answer 6

50% asymptomatic and diagnosed on blood count

symptoms of BM failure:

• anaemia (fatigue, dizziness)
• neutropenia - recurrent infections
• thrombocytopenia - easy bruising, epistaxis

RF

Question 7

signs of myelodysplasia

Answer 7

signs of BM failure

• anaemia - pallor, cardiac flow murmur
• neutropenia - infections
• thrombocytopenia - purpura or ecchymoses
• gum hypertrophy and lymphadenopathy
• spleen NOT enlarged - except in CMML

Question 8

Ix for myelodysplasia

Answer 8

blood - FBC = pancytopenia, low reticulocytes

blood film

bone marrow aspirate/biopsy

Question 9

blood film for myelodysplasia

Answer 9

normocytic or macrocytic red cells

ovalomacrocytosis

variable microcytic red cells in RARS,

reduced granulocytes

granulocytes have reduced or absent granulation and bilobed ‘Pelgeroid’ nucleus

increased monocytes (CMML)

myeloblasts

Question 10

bone marrow aspirate/biopsy for myelodysplasia

Answer 10

hypercellularity because of ineffective haematopoiesis

ringed sideroblasts - (haemosiderin deposits in the mitochondria of erythroid precursors form an apparent ring around the nucleus) with dyserythropoietic features, abnormal granulocyte precursors and mega-karyocytes.

10 % show marrow fibrosis.

Question 11

Answer 11

ringed sideroblasts

found in sideroblastic anaemia (ie myelodysplasia)