pancytopenia Flashcards
what is pancytopaenia
a deficiency of blood cells of all lineages (generally excludes lymphocytes)
which cells are most affected in pancytopenia
RBCs
platelets
granulocytes
what cells are present the pathway of the maturation of an RBC
pronormoblast early normoblast intermediate normoblast late normoblast reticulocyte RBC
what cells are present in the pathway of neutrophil maturation
myeloblast promyelocyte myelocyte metamyelocyte band neutrophil segmented neutrophil
what are the average lifespans for RBCs, neutrophils and platelets
RBCs: 120 days
neutrophils: 7-8 hours
platelets: 7-10 days
causes of reduced production of all cell types
inherited syndromes causing bone marrow failure
acquired bone marrow failure (primary or secondary)
what are the clinical features of Fanconi’s anaemia
short stature skin pigment abnormalities hypogenitalia endocrinopathies GI/CV/renal defects haematological symptoms
haematological abnormalities in Fanconi’s anaemia
macrocytosis followed by thrombocytopenia, then neutropenia
bone marrow failure by 20 years
increased leukaemia risk
examples of primary bone marrow failure
idiopathic aplastic anaemia (autoimmune attack of haemopoietic stem cells)
myelodysplastic syndromes
acute leukaemia
which cells are responsible for autoimmune attack in aplastic anaemia
auto-reactive T cells
release IFN-gamma and TNF-alpha
what are features of myelodysplastic syndromes
dysplasia (disordered development)
hypercellular marrow
increased apoptosis of progenitor and mature cells (ineffective haemopoiesis)
myelodysplastic syndromes carry a risk of evolving into…
acute myeloid leukaemia
why can leukaemia cause pancytopenia
proliferation of abnormal cells (blasts) from leukaemia stem cells results in failure to differentiate or mature into normal cells
what can cause secondary bone marrow failure
drug induced (eg chemotherapy, chloramphenicol, alcohol): causes aplasia
B12/folate deficiency: abnormal nuclear maturation
infiltrative (non-haemopoieotic malignant infiltration, lymphoma)
viral/storage diseases
what can cause increased destruction of all cell types
hypersplenism
vascular supply of the spleen
splenic artery (coeliac axis) splenic vein (with SMV forms portal vein)
how does hypersplenism cause pancytopaenia
increased splenic pool results in increased destruction of cells
that exceeds bone marrow capacity for production
what can cause hypersplenism
splenic congestion: portal HTN, congestive cardiac failure
system disease: RA
haematological diseases: splenic lymphoma
clinical features of pancytopaenia
anaemia: fatigue, SOB, CV compromise
neutropenia: infections (severity/duration)
thrombocytopenia: bleeding (purport, petechiae, visceral bleeds)
what investigations should be done following FBC and blood film
depending on results: B12/folate LFTs virology autoantibody tests bone marrow examination
what is bone marrow trephine biopsy
take a little bit of bone away
how does marrow cellularity reflect the cause of pancytopenia
hypocellular: aplastic anaemia
hypercellular: myelodysplastic syndromes (proliferation and apoptosis), B12/folate deficiency, hypersplenism
examples of supportive treatment in pancytopenia
red cell/platelet transfusions
(neutrophil transfusions not routine)
antibiotics prophylaxis/treatment
how should neutropaenic fever be managed
treat promptly with empiric antibiotics without waiting for microbiology results
specific management of primary bone marrow disorders
malignancy: chemo
congenital: bone marrow transplant
idiopathic aplastic anaemia: immunosuppression
specific management of secondary bone marrow disorder
drug reaction: stop drug
viral: treat virus
B12/folate: supplements
specific management of hypersplenism
treat cause if possible
consider splenectomy
