Haem Flashcards
Contents of cryoprecipitate
Factor 8 Factor 13 Fibrinogen Fibronectin Von wilebrand factor
Haemochromatosis mutations
H63D
C282Y
Both mutations in the HFE gene (human haemochromatosis gene), gene product is HH protein which regulates hepcidin production.
Homozygous c282y most common clinical haemochromatosis
Heterozygous compound c282y/h63d mild, homozygous H63D
Heterosexual h63d rarely clinically seen
Most sensitive test for diagnosing haemochromatosis
Transferrin saturation- more than 50% in women and 60% in men
How do you tell the difference between haemophilia a and b on lab testing
You cannot- lab wise indistinguishable
Clinically haemophilia B (factor 9 def) can present in adulthood, not really for haem A. Mixing study will correct prolonged ATPP in congenital but only partially in acquired factor 8 deficiency
Factor 5 def get long PT and APTT
Factor twelve def gives long APTT but normal PT as well but no actual bleeding manifestations
Causes of isolated long APTT
Low 8,9,12, 11
Acquired clotting factor inhibitors against factor 8
Lupus anticoagulant
Plus minus also prolonged PT- UFH, anti phospholipid Ab
Inherited thrombophilias
More potent: protein c, protein s, anti thrombin deficiencies
Less potent more common: prothrombin G20210A gene mutation, factor v Leiden
Percentage of JAK 2 in PRV, IMF, ET
95% for PRV
50-60% for others
Name of effect where taking spleen out attenuated the disease process
Abscopal effect
Hyper viscosity clinical triad
Visual changes, mucosal bleeding, mental state changes
To diagnose waldenstroms macroglobulinaemia need 2 things…
Greater than ten percent lymphoplasmocytic bone marrow cellularity and IgM M protein
What is the use of serum transferrin receptor
Derived from BM erythroid precursors, hence increase with increasing erythropoesis. Inversely proportional to iron levels eg low iron gives high level
Not as specific as low ferritin
What is free transferrin receptor/log ferritin ratio use?
Better than serum free transferrin receptor at differentiating ACD from iron def anaemia.
Less than one - ACD
more than two - iron def
More than 2 could also mean both
Causes of B12 def
Pernicious anaemia, bariatric surgery, gastritis, autoimmune metaplastic strophic gastritis
Malabsorption syndrome, Crohn’s disease, blind intestinal loops, ileal resection or bypass, fish tapeworm infection
Pancreatic insuff
Strict vegan or pregnant plus veg
Agents that block absorption - biguanides, h2 receptor antag, ppis, N2o anaesthesia, neomycin
Inherited transcobalmin II def
Role of methylmalonic acid and homocysteine levels in suspected B12 and folate def
Folate def–> sensitive high levels homocysteine
B12 def–> sensitive high levels both MMA and homocysteine
These are metabolites waiting around to be processed but no B12 or folate to help
Useful when borderline levels of tests
Ab testing in pernicious ansemia
Intrinsic factor Ab not sensitive (50-70%) but specificity approaching 100%
Anti parietal cell ab more sensitive but less specific
Increase in serum gastrin, decreased pepsinogen 1 and decreased pepsinogen 1:2 highly sensitive but not specific
Cold agglutinin causes
Cold IgM ab AIHA lymphoproliferative disorders Mycoplasma Mononucleosis EBV HIV Drugs Idiopathic
Immune DAT + causes
Post transfusion Drugs SLE CLL idiopathic