Aneamia Flashcards
What is aneamia? What are the main causes?
Reduced amount of Haemoglobin based on the reference range.
Low Hb usually also comes with lower RBC and Hct
Mostly caused by decrease of absolute Hb, not increased plasma volume
What are the 4 mechanisms leading to Aneamia?
Reduced production of RBC, Loss of blood from body, Reduced survival of RBC, Pooling of red cells in the spleen
These mechanisms also usually have causes
What is the cause of Reduced RBC production?
Either caused by issue of globin production, or Haem production (like caused by low iron)
How does cell size help suggest causes of Aneamia?
Microcytic (usually also hypochromic), normocytic (normochromic) and macrocytic (normochromic)
What are the common causes of Microcytic Aneamia?
Defects in haem synthesis-Iron deficiency, aneamia of chronic disease (like TB, or other-iron blocked in macrophages)
Defects of globin-thalassemia-alpha or beta thalassemia (can be gamma in neonates)
What are the common causes of Macrocytic aneamia?
Usually result from abnomral haemotopoesis-Red cell preudsor continues to synthesis heam, or divide properly
Can be: Megaloblastic-delayed in maturation of the nucleus-large+has nucleus ->should marrow examination
(can usually just masure B12/Folic and work)-
Can be: premature release of cells (reticulocytes are 20% larger-if increased, MCV up-Recent blood loss, heaolytic aneamia
usually caused by B12, folic acid and some drugs (like some that interact by DNA), Liver disease, ethanol toxciciy, Recent blood loss,
What are mechanisms of Normocytic aneamia?
Recent and large blood loss, failure of production of RBC, Pooling of RBC in the spleen (liver cirrosis, splenic damage from Sicklecell)
What are the main causes of normocytic aneamia?
Ulcers, varices, Trauma,
FAilure of prod of RBC (early stages of Fe def, renal failure, Bone marrow failure/supression, bone marrow infiltration-cancer)
Hypersplenism (portal cirrhosis)
What is heamolytic aneamia?
Aneamia Resulting from shortened RBC survival
Can be intrinsic to the RBC (Inherited-abnormalities in memebrane, heam, enzymes, (like SC)) or exrinsic factors acting of RBC (Acquired usually-infection, drugs, etc)
The extrinsic factors can precipitate lesser intrisic defaults
What is intra/extra vascular haemolytic aneamia?
Describes if its happening in the veins (something very wrong with RBC) or being removed by macrophages outside of veins
When should you suspect heamoloytic aneamia?
Unexplained aneamia-normacytic/Macrocytic
Evidence of morphalogically RBC
Evidence of increased RBC breakdown (jaundice, bilirubin. gallstones in youngs)
Evidence of increased Bone marrow activity
What is hereditary Spherocytosis? How can you detect and treat it?
heamoloytic abnormalities that cause it.
Start of as normal, but as they mature lose some membrane-less flexible and removed early
usually extravascular, as they get trapped by the spleen with their weird shape
usually increase synthesis in exchange-polychormia and stuff
Heamolysis can cause jaundice
Only treatment is spleenectomy-but has its own risks (immune issues) -also need to measure folic acid lvls/take supplements
What is Glucose 6 phosphate deficiency for RBC?
more common in some ethnic groups (mediteraniean and african)
Important enzyme in pentose phosphate Shunt-essensital for RBC protection from oxidation damage, drugs, foods
Enzyme can be damaged by some stuff (like naphtalene)
On the X chr, so usually affects males,
Usually causes SEVERE Intravascular heamolysis (but still need oxidant to trigger. rare constant)
Will lead to Heinz bodies in the blood, detectable (look like ICC)-condensed heam all on one side
treat with transfusion, then prevent oxidations risks
What is Autoimmune heamolytic aneamia?
AID to RBC-Ab to RBC, then macrophages either “bite” or destroy the cell
usually happens in spleen/liver
Spherocytes, reiculcytes, measure ABs
Treated with corticosteroids -splenosectomy for severe cases.
What is microangiopathic aneamia?
Many causes, treatment depends
Microangiopathic hemolytic anemia (MAHA) is a microangiopathic subgroup of hemolytic anemia (loss of red blood cells through destruction) caused by factors in the small blood vessels.
usually: remove the cause (hypertension, or causative drug)
Can be AB in plasma leading to fibrim deposition (damaged RBC, platelets, Thrombosys)
