Pancytopenia Flashcards
what is pancytopenia
generalised deficiency of blood cells of all lineages (generally excludes lymphcocytes)
what cells are affected most in pancytopneia
erythrocytes
platelets
granulocytes
is pancytopenia a diagnosis
no
does pancytopenia always mean marrow failure
no
how long is a RBCs lifespan
~120 days
how long is a neutrophils lifespan
~7-8 hours
how long is a platelets lifespan
7-10 days
what are the two mechanisms behind pancytopenia
reduced production (marrow failure) or increased destruction (hypersplensim)
what are the categories of marrow failure
inherited syndromes
acquired: primary and secondary
what causes inherited marrow failure syndromes
defects in DNA repair/ ribosomes creates triad of cancer pre-disposition, impaired haemopoeisis and congenital anomalies
what is fanconis anaemia
inherited marrow failure syndrome:
- short stature and skeletal abnormalities
- skin pigment (cafe au lait spots) abnormalities
- hypogenitalia
- GI defects
- endocrineopathies
- cardio/ renal/ haem problems
what haem abnormalities occur in inherited marrow failure syndrome
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
what causes a primary acquired bone marrow failure
an intrinsic marrow problem (usually stem cell defect)
- idiopathic aplastic anaemia (AI attack against stem cells)
- myelodysplastic syndromes
- acute leukaemia
what cells are reduced in aplastic anaemia
erythrocytes
platelets
granulocytes
what are the features of myelodysplastic syndromes
dysplasia
hypercellular marrow
increases apoptosis of progenitor and mature cells (ineffective haemopoiesis)
PROPENSITY FOR EVOLUTION INTO AML