Bone Marrow Failure

Question 1

What occurs in bone marrow? Where does this occur?

Answer 1

Haematopoiesis

Central skeleton : vertebrae, sterum, ribs, skull) and proximal long bones

Question 2

Why does organomegaly occur?

Answer 2

Extramedullary haematopoiesis - in liver and spleen when increased demand in some anaemias

Question 3

What is pancytopenia?

Answer 3

Reduction in:
Red cells
Whites cells
Platelets

Question 4

What are causes of pancytopenia?

Answer 4

Reduced marrow production:
- Aplastic anaemia
- Infiltration: 
Acute leukaemia
Myelodysplasia
Myeloma
Lymphoma
Solid tumours
Myelofibrosis

Increased peripheral destruction:
Hypersplenism

Question 5

What is agranulocytosis?

Answer 5

Granulocytes (WBCs with neutrophil, basophil or eosinophil granules) have stopped being made

This leaves pateint at risk fo infection

Question 6

What drugs can cause agranulocytosis?

Answer 6

Carbimazole
Procainamide
Sulfonamdes
Clozapine

Question 7

What should you warn patients on agranulocytosis causing drugs?

Answer 7

Report any fever
Neutropenia may be sore throat
Stop drug and commence neutropenic regimen and consider GCSF

Question 8

What are early problems in pancytopenia? Why?

Answer 8

Neutropenia (neurotrophils survive 1-2d)
Thrombocytopenia (platelets survive 8d)

Later, anaemia (RBC 120d)

Question 9

What is management for pancytopenia?

Answer 9

Red cell transfusion - 1U should raise Hb by 10-15g/L

Platelets - stored at room temperature
Transufse if:
Platelets <10
Haemorrhage
Before invasive procedures (Biopsy, LP)

Neutropenia:
Use neutropenic regimen when <0.5
Full barrier nursing
Look for infection
Take swabs
FBC, platelets, INR, U&amp;E, LFT, LDH, CRP
Cultures - 3 peirpehrally, Hickmann line
Urine
Sputul
Stool
CXR
Fluconazole for candida prophylaxis

Piperacillin/tazobactam (+vancomycin for gram +ve)
Co-trimoxazole for pneumocystis pneumonia
Consider TB

Question 10

Where are bone marrow biopsies taken? What is each for?

Answer 10

Aspirate and trephine from posterior iliac crest

Aspirate provides film for microscopy

Trephine is a core of bone which allows assessment fo cellularity, architecture and infiltration of disease

Question 11

What is aplastic anaemia? Causes?

Answer 11

Stem cell disorder in which bone marrow stops making cells
This leads to pancytopenia

Autoimmune
Triggered by drugs, viruses, irradiation
May be inherited - Fanconi anaemia

Question 12

How does aplastic aneamia present?

Answer 12

Anaemia - tiredness, lethargy, pallor
Infection
Bleeding

Question 13

What is mx for aplastic anaemia?

Answer 13

Supportive

Transfuse product if required
Initiate neutropenic regimen if count < 0.5

Allogenic bone marrow transplant from HLA matched sibling

Immunosuppression with ciclosporin

Question 14

What is neutropenia regimen?

Answer 14

Full barrier nursing
Look for infection
Take swabs
FBC, platelets, INR, U&E, LFT, LDH, CRP
Cultures - 3 peirpehrally, Hickmann line - line infection
Urine culture
Sputum culture
Stool culture
CXR
Fluconazole for candida prophylaxis

Piperacillin/tazobactam (+vancomycin for gram +ve)
Co-trimoxazole for pneumocystis pneumonia
Consider TB

Psuedomonas in vase containing flowers