Haem 7: Myelodysplastic syndromes + aplastic anaemia

Question 1

What are myelodysplastic syndromes?

Answer 1

Acquired haematopoietic stem cell disorders

Dyplastic changes w/ 1+ myeloid lines (erythroid, megakaryote or granulocyte)

Question 2

What are the presentations of myelodysplastic syndromes?

Answer 2

Usually asymptomatic, but risk of progression to AML

Present with incidental cytopenia

Question 3

What are myelodysplastic syndromes classifed by?

Answer 3

Classification is based on:
Number of dysplastic lineages
Percentage of blasts
Cytogenetics
% ringed sideroblasts
Number of cytopaenias

Multilineage + higher amounts of blasts = worse prognosis

(>20% blasts - definition of AML)

Question 4

Prognosis of MDS?

Answer 4

Rule of thirds:
1/3 die from infection
1/3 die from bleeding
1/3 die from leukaemic transformation (acute leukaemia)

Risk is assessed using IPSS score

Question 5

Mx of MDS?

Answer 5

Survival:
Allogenic stem cell transplant
Intensive chemo

Supportive:
Bloods, antimicrobials + growth factors (EPO, F-CSF)

Biological modifiers:
Immunosupressive + azactuadine, decitabine, lenzalidomide

Question 6

What is aplastic anaemia?

Answer 6

Damage to pluripotent haematopoietic stem cells impairs production of all peripheral blood cells – RARE

Question 7

Cause of aplastic anaemia?

Answer 7

Most Aplastic Anaemia is idiopathic (possibly due to immune attack on the stem cells), and has a bimodal incidence (15-24 years and 60+ years)

Damage to more differentiated stem cells can cause select cytopaenias.

Question 8

How can aplastic anaemia present? Ix?

Answer 8

TRIAD of Anaemai, Infection and Bleeding / bruising

ix involves BM biospy

Question 9

In aplastic anaemia what is associated with a worse prognosis?

Answer 9

A low reticulocyte count is associated with severe disease with a worse prognosis - Reticulocytosis often indicates a high turnover of red blood cells, perhaps due to destruction of or decreased life span of peripheral erythrocytes (as in haemolytic anaemia), but low reticulocytes indicate that the bone marrow has stopped functioning to the point that it cannot even produce very immature forms of RBC (reticulocytes).