Session 6: Haematology in Systemic Disease Flashcards
Explain how chronic disease or chronic inflammation can lead to anaemia of chronic disease.
A chronic inflammatory condition such as RA, chronic infections such as tuberculosis or malignancy will lead to a chronic release of cytokines such as IL-6. IL-6 is particularly important in this case as it leads to an increased production of hepcidin by the liver.
Increased hepcidin leads to decreased ferroportin expression and promotion of internalisation of ferroportin molecules. This leads to a functional loss of iron. This means that there is still a normal total iron store in the body, but it is not available for utilisation for erythropoiesis in bone marrow.
Decreased iron release from reticuloendothelial system and a decreased iron absorption in the gut.
There is also an inhibition of EPO production by kidney due to IL-6.
What type of anaemia is anaemia of chronic disease?
Microcytic anaemia
Primary treatment of anaemia of chronic disease?
Treat underlying disorder.
Explain how chronic kidney disease can lead to anaemia.
Numerous of causes can lead to anaemia due to chronic kidney disease.
Deficiency in EPO due to the kidney disease will lead to less production of RBCs.
Damaged kidneys can also lead to reduced renal clearance of hepcidin. This can lead to the same mechanism of anaemia of chronic disease where there is a lack of functional iron.
Kidney dysfunction can also lead to ureamia where there is an increased level of urea in blood because it isn’t being filtered properly. The increased urea concentration leads to inhibition of erythropoiesis and reduces the lifepsan of existing RBCs. Also inhibits platelet function.
What kind of anaemia is chronic kidney disease?
Usualy normochromic and normocytic.
How does the severity of anemia relate to the severity of chronic kidney disease?
The lower the GFR (glomerular filtration rate) the worse the anaemia.
Treatment/management of chronic kidney disease anaemia.
Recombinant EPO however it is important the patient has sufficient iron, folate and B12 for the EPO to work.
Side-effects of recombinant EPO treatment.
Hypertension
Seizures
Blood clotting during dialysis
Explain how RA can cause abnormal blood counts.
(Not functional iron deficiency related)
Disregarding functional iron deficiency in this case:
Flares of the disease can cause neutrophilia and thrombocytosis. Some anti-rheumatic drugs can cause thrombocytopenia and/or neutropenia through marrow suppression and immune causes or folate inhibition.
What is Felty’s syndrome?
A triad of RA, splenomegaly and neutropenia.
Explain how alcoholism can lead to anaemia.
Excessive alcohol consumption has a range of adverse effects on marrow, spleen and blood cells. The toxic effect of alcohol leads to suppression of haematopoiesis resulting in production of structurally abnormal blood cells.
Acetaldehyde also produce protein-acetaldehyde adducts on RBCs leading to immune response to the modified proteins and destruction of the RBCs.
Cirrhosis of liver also causes abnormal production of some of the clotting factors and lead to gastrointestinal bleeding contributing to the anaemia.
Portal hypertension can lead to congestive splenomegaly, splenic trapping of red cells, white cells and platelets.
What type of anaemia is alcoholism related anaemia?
Macrocytic.
Label
Post-operative changes reactive changes of blood cells.
Major surgery mild thrombocytosis or neutrophilia can occur.
Anaemia can occur due to blood loss or dilution.
Worsening neutrophilia or thrombocytosis can be due to infective complication following surgery like S. aureus or S. epidermidis.
DIC can also occur.
Immobile patients are more likely to develop DVTs particularly in the context of cancer, dehydration or pelvic/orthopaedic surgery.
What happens to blood cells in splenectomy?
High rebound thrombocytosis and lymphocytosis which can persist. Howell-Jolly bodies will be seen in red cells as well.
