Haematology 13 - Myelodysplastic syndromes and aplastic anaemias

Question 1

What are the possible causes of death in myelodysplastic syndromes?

Answer 1

1/3 die of bleeding
1/3 die of infection
1/3 die of AML

Question 2

What are the 2 possible curative treatments for myelodysplastic syndromes, and what is the biggest issue with them?

Answer 2

1. Allogenic stem cell transplant
2. Intensive chemotherapy
   Sadly, most patients can’t benefit from either for one reason or another

Question 3

In myelodysplastic syndrome patients who are not suitable for curative treatment, how should disease be managed?

Answer 3

Supportive treatments include: 
- Blood products
- Antibiotics
- GF
Can add biological modifiers: 
- Immunosuppressive therapy
- Azacytidine

Question 4

How does azacytidine work in the treatment of myelodysplastic syndromes?

Answer 4

Hypomethylating agent

Causes blood count to rise

Question 5

Recall 3 drugs that can cause bone marrow failure

Answer 5

1. Cytotoxic drugs (eg chemo)
2. Antibiotics (particularly chloramphenicol)
3. Thiazide diuretics

Question 6

What is the age distribution of aplastic anaemia?

Answer 6

Bimodal
Peak 1: 15-24 years
Peak 2: >60 years

Question 7

What are the possible causes of aplastic anaemia

Answer 7

Idiopathic in 75%
Inherited causes: 
- Fanconi's anaemia
- Dyskeratosis anaemia
- Schwachman-Diamond syndrome
Acquired causes: 
- Herpes viruses
- SLE

Question 8

What are the 2 classifications of aplastic anaemia, and how is classification decided?

Answer 8

Severe or non-severe
Decided by Camitta criteria:
- Aplastic anaemia is severe if 2 or more of the following peripheral blood features are present:
- Reticulocytes <1%
- Neutrophils <0.5
- Platelets <20
PLUS: Bone marrow cellularity must be <25%

Question 9

How should idiopathic aplastic anaemia be treated?

Answer 9

For all patients: androgens (oxymethalone)
For older patients: immunosuppression
- anti-lymphocyte globulin
- ciclosporin
For younger patients: stem cell transplant

Question 10

Recall some symtoms of Fanconi’s anaemia

Answer 10

Short stature, hypogonadism, thumb abnormality, cafe au lait spots

Question 11

What is the triad of clinical features of dyskeratosis congenita?

Answer 11

1. Skin pigmentation
2. Nail dystrophy
3. Oral leukoplakia
   “SNOB” = the above triad + BM failure - useful mnemonic

Question 12

What is the genetic basis of dyskeratosis congenita?

Answer 12

Telomere shortening

Question 13

What is the pseudo-pelger-huet anomaly?

Answer 13

Hyposegmented neutrophils seen in myelodysplastic syndromes

Question 14

Recall the options for treatment in essential thrombocytosis

Answer 14

1. Aspirin (to reduce thrombus formation)
2. Anagrelide (reduced formation of platelets from megakaryocytes)
3. Hydroxycarbamide