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Flashcards in Pancytopenia Deck (30)
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1
Q

what is pancytopenia

A

generalised deficiency of blood cells of all lineages (generally excludes lymphcocytes)

2
Q

what cells are affected most in pancytopneia

A

erythrocytes
platelets
granulocytes

3
Q

is pancytopenia a diagnosis

A

no

4
Q

does pancytopenia always mean marrow failure

A

no

5
Q

how long is a RBCs lifespan

A

~120 days

6
Q

how long is a neutrophils lifespan

A

~7-8 hours

7
Q

how long is a platelets lifespan

A

7-10 days

8
Q

what are the two mechanisms behind pancytopenia

A
reduced production (marrow failure) 
or
increased destruction (hypersplensim)
9
Q

what are the categories of marrow failure

A

inherited syndromes

acquired: primary and secondary

10
Q

what causes inherited marrow failure syndromes

A

defects in DNA repair/ ribosomes creates triad of cancer pre-disposition, impaired haemopoeisis and congenital anomalies

11
Q

what is fanconis anaemia

A

inherited marrow failure syndrome:

  • short stature and skeletal abnormalities
  • skin pigment (cafe au lait spots) abnormalities
  • hypogenitalia
  • GI defects
  • endocrineopathies
  • cardio/ renal/ haem problems
12
Q

what haem abnormalities occur in inherited marrow failure syndrome

A

usually occur by ~7
UNABLE TO CORRECT INTER-STRAND CROSS LINKS (DNA damage)

get macrocytosis -> thrombocytopenia -> neutropenia

84% bone marrow failure (aplasia) by 20
52% leukaemia by 40

13
Q

what causes a primary acquired bone marrow failure

A

an intrinsic marrow problem (usually stem cell defect)

  • idiopathic aplastic anaemia (AI attack against stem cells)
  • myelodysplastic syndromes
  • acute leukaemia
14
Q

what cells are reduced in aplastic anaemia

A

erythrocytes
platelets
granulocytes

15
Q

what are the features of myelodysplastic syndromes

A

dysplasia
hypercellular marrow
increases apoptosis of progenitor and mature cells (ineffective haemopoiesis)
PROPENSITY FOR EVOLUTION INTO AML

16
Q

how can acute leukaemia cause pancytopenia

A

proliferation of abnormal ‘blast’ cells

failure to differentiate/ mature into normal cells

17
Q

what can cause secondary bone marrow failure

A

drug induced: chemotherapy, chloramphenicol, alcohol (all cause aplasia)
B12/folate deficiency (nuclear maturation can affect all lineages- will be hypercellular)
infiltrative: non haemopoietic malignant infiltration, lymphoma
viral (e.g. HIV)
storage diseases

18
Q

what type of lymphoid tissue is the spleen

A

secondary lymphoid organ

19
Q

what is the blood supply to the spleen

A

splenic artery (branch on coeliac) drained by splenic vein (with SMV forms portal vein)

20
Q

hows does hyperplenism cause pancytopenia

A

increased splenic pool (trapping of platelets in spleen)
increased transit time through spleen for cells
increased destruction exceeds bone marrow capacity

21
Q

what can cause hypersplenism

A
splenic congestion (portal hypertension, congestive cardiac failure) 
systemic diseases (RA)

haematological diseases (splenic lymphoma)

22
Q

what clinical problems make up pancytopenia

A

anaemia
neutropenia
thrombocytopenia

23
Q

what are the clinical features of pancytopenia

A

anaemia: fatigue, SOB, cardiovascular compromise
neutropenia: infections
thrombocytopenia: bleeding (purpura, petechiae, ‘wet bleeds’ e.g. visceral bleeds)

features of the cause of the pancytopenia

24
Q

how can you find the cause of pancytopenia

A
Hx 
FHx
clinical findings
FBC, blood film
B12/ folate, LFTs, virology, autoantibody 
bone marrow examination 
cytogenetics  (e.g. fanconis syndrome)
25
Q

what is marrow cellularity like in aplastic anaemia IMPORTANT

A

hypocellular

26
Q

what causes marrow hypercellularity in pancytopenia IMPORTANT

A
myelodysplastic syndromes (porliferation and apoptosis) 
B12/folate deficiency  late maturation failure, early proliferation + apoptosis)
hypersplenism
27
Q

what is the treatment for pancytopenia

A

supportive : red cell and platelet transfusions (platelets transfusions not routine), antibiotic and antifungal prophylaxis (treat neutropenic fever ASAP)
specific- dependent on cause (e.g. B12/ folate deficiency)

28
Q

what are the treatments for primary bone marrow disorders

A

malignancy- chemo
congenital- bone marrow transplantation
idiopathic aplastic anaemia- immunosuppression

29
Q

what are the treatments for secondary bone marrow disorders

A

drug reactions- STOP
viral- treat
replace B12/folate

30
Q

what is the treatment for hypersplenism

A

treat cause if possible

consider splenectomy