Pancytopenia Flashcards
what is pancytopenia
a deficiency of blood cells of ALL lineages (however generally excluded lymphocytes)
what is the lifespan of red cells, neutrophils and platelets
red cells - 120 days
neutrophils 7-8 hours
platelets 7-10 days
causes of pancytopenia
reduced production (bone marrow problems)
increased destruction
causes of reduced production pancytopenia
Bone marrow failure
- inherited
- acquired (primary or secondary)
characteristics of inherited marrow failure syndromes
v rare
Fanconi’s Anaemia
- short stature
- skeletal abnormalities
- skin pigment abnormalities
- radial ray abnormalities
- hypogenetalia
- endocrinopathies
- GI defects
- cardiovascular defects
- renal defects
- haematological defects
what haematological abnormalities are seen in Fanconi’s Anaemia
unable to correct DNA damage
Macrocytosis followed by thrombocytopenia then neutropenia
84% risk of bone marrow failure by age 20
leukaemia risk 52% by age 40
median age 7 years
Types of acquired bone marrow failure
Primary - an intrinsic marrow problem
Secondary
Causes of primary acquired bone marrow failure
Idiopathic aplastic anaemia
-autoimmune attack against haemopoietic stem cells
Myelodysplastic syndromes
Acute leukaemia
-white cell count can be variable
what happens in idiopathic aplastic anaemia
auto-reactive T cells target haemopoeitic stem cells and myeloid progenitors
stops the production of myeloid cells
- erythroblasts
- platelets
- granulocytes
what are myelodysplastic syndromes
Hypercellular marrow with disordered development
increased apoptosis of progenitor and mature cells (ineffective haemopoiesis)
can become acute myeloid leukaemia
how can acute leukaemia cause pancytopenia
proliferation of abnormal blast cells from leukaemic stem cells
failure to differentiate into mature of normal cells
therefore there is a lack of normal mature cells but lots of abnormal blasts
causes of secondary bone marrow failure
drug induced (chemotherapy, chloramphenicol, alcohol)
B12/folate deficiency (nuclear maturation can affect all lineages)
non-haemopoieotic malignant infiltration
miscellaneous (viral, storage disease)
Causes of increased destruction pancytopenia
hypersplenism
- increased splenic pool
- increased destruction that exceeds bone marrow capacity, usually associated with significantly enlarged spleen
what is the splenic pool of a normal spleen
red cell mass 5%
red cell transit fast
splenic platelet pool 20-40%
what is the splenic pool in hypersplenism
red cell mass 40%
red cell transit slow
splenic platelet pool 90%
what causes hyperspenism
any cause of splenomegaly can potentially cause it
splenic size however does not always correlated with hypersplenism
-splenic congestion
(portal hypertension, congestive cardiac failure)
- systemic diseases (rheumatoid arthritis)
- haematological disease (splenic lymphoma)
clinical features of pancytopenia
lack of circulating red blood cells
the cause of the pancytopenia
what is marrow cellularity in aplastic anaemia
hypo cellular
what is marrow cellularity hyper cellular in pancytopenia
myelodysplastic syndromes
B12/folate deficiency
hypersplenism
treatment for pancytopenia
supportive
- red cell transfusion
- platelet transfusion
- neutrophil transfusions not routine
antibiotics/prophylaxis - treat neutropenic fever with empirical antibiotics before lab results back
specific (depends on cause)
treatment for primary bone marrow disorders
malignancy - chemo
congenital - transplant
idiopathic aplastic anaemia - immunosuppression
treatment for secondary bone marrow disorders
drug reaction - stop drug
viral - treat
B12/folate deficiency - replace
treatment for hypersplenism
treat cause if possible
consider splenectomy if not
