Flashcards in Week 3 HRM Deck (54)
What would the MCV value be in microcytic anemias?
What would the MCV value be in macrocytic anemias?
What would the MCV value be in normocytic anemias?
Name the 4 microcytic anemias
Iron deficiency, thalassemia, anemia of chronic disease and sideroblastic anemia
What is TIBC
Total iron binding capacity
What laboratory tests would be done for IDA?
Serum iron levels, TIBC, bone marrow iron stain, serum ferritin levels, RDW
What laboratory tests would be done for megaloblastic anemia?
Vitamin B12 and folate levels, liver and thyroid function test, bone a,row biopsy
What laboratory tests would be done for Hemolytic anemias?
Morphology, reticulocyte count, Coombs test( direct and indirect) Hb electrophoresis
What is the most common anemia?
Iron deficiency anemia
Name some common(aetiology) causes of IDA?
Bleeding, nutritional problems,worms, cancers, pregnancy, childhood
Discuss the pathogens is of IDA
Low Hb because of low iron, normal DNA with increased divisions due to hypoxia stimulating EPO. Iron is needed for cytochrome enzymes so epithelium is affected also. Smaller because there is less Hb
Describe the morphology of IDA
Microcytic, hypochromic, decreased central pallor, pencil cells, Anisocytosis and poikilocytosis
List some causes (aetiology) of megaloblastic anemia
Vitamin B12/ folate deficiency, gastritis, gastric atrophy(no intrinsic factor), cancer, old age, alcoholism, liver disease, hypothyroidism
Describe the pathogenesis of megaloblastic anemia
Abnormal DNA synthesis therefore there are decreased cell divisions
Affects WBCs and RBCs
List some clinical features of IDA?
Anemia, koilonychias(brittle spoon nails), esophagitis, glossitis (smooth shiny tongue), stomatitis, pale skin
List some clinical features of megaloblastic anemia
Stomatitis, anemia, jaundice, glossitis, chelates, neurological symptoms
Describe the morphology of megaloblastic anemia
Hypersegmented neutrophils, oval macrocytes, anisopoikilocytosis, polychromatophils, pancytopenia
Why do hyper segmented neutrophils disappear after only 14 days of treatment for megaloblastic anemia?
Because WBCs have a short lifespan and are replaced regularly
What is anemia of chronic diseas?
Anemia where iron is blocked from being stored in RBC precursors. The body has enough iron but it is unable to be accessed by the developing erythrocytes
What is the role of hepcidin in iron homeostasis?
It is a polypeptide produced by the liver that inhibits the release of iron from macrophages and intestinal epithelial cells via its interaction with the transmembrane iron transporter ferroportin
Why does inflammatory stimuli cause anemia in anemia of chronic disease?
Inflammatory stimuli activates monocytes and T cells, the T cells the Increase hepatic (liver) synthesis of hepcidin and decrease erythropoietin release . As this occurs, hepcidin inhibits iron release and erythropoiesis is also decreased.
Name some inflammatory mediators
IFN, TNF, IL-6
Describe some causes of anemia of chronic disease?
Rheumatoid arthritis, diabetes, Ct diseases, chronic infections, renal failure, inflammation, renal cell carcinoma
Describe clinical features of anemia of chronic disease?
Mild anemia, does not respond to nutritional supplements
Describe morphology of anemia of chronic disease?
Normal to microcytic cells, hypochromic
What are some lab roster indicators of anemia of chronic disease?
Having a chronic disease, low iron saturation and TIBC , reduced EPO and reticulocytes, increased ferritin
What is aplastic anemia?
Substantial reduction in number of haematopoietic stem cells and a fault in the remaining stem cells, that makes them unable to divide and differentiate sufficiently to populate the bone marrow. Replacement of marrow is by fatty yellow marrow
List some causes of aplastic snemia
Half cases are idiopathic, chemotherapy, toxic chemicals, radiation, viral infections, drugs
Clinical features of aplastic anemia?
Anemia, infections of throat and mouth, bleeding gums, bruising
Morphology of aplastic anemia?
Pancytopenia, norpmochromic, normocytic, low reticulocyte count
What antibody is responsible for warm type autoimmune Hemolytic anemia?
What are some causes for warm type autoimmune Hemolytic anemia?
Idiopathic , drugs, viral infections, autoimmune disorders
What is the pathogenesis for warm autoimmune Hemolytic anemia?
IgG antibody coasts the RBC with receptors and the resident macrophages gradually remove it's membrane . It is destroyed prematurely predominantly in the spleen (extravascular)
Why is it called warm autoimmune Hemolytic anemia?
Because he antibodies can function in warm and cooler temperatures
Why is it called cold autoimmune Hemolytic anemia?
Because the IgM antibody can only function in regions of cooler blood such as finger tips and earlobes. Best functions at 4 degrees
Clinical features for warm autoimmune Hemolytic anemia?
Spleenomegaly, any age, any gender, anemia
Morphology for warm autoimmune Hemolytic anemia?
Spherocytes (no central pallor), increased reticulocytes with bluish tinge in blood film,
What antibody is responsible for cold type autoimmune Hemolytic anemia?
Causes for cold type autoimmune Hemolytic anemia?
Idiopathic, infections (pneumonia, mononucleosis), lymphoma, autoimmune disorders
Pathogenesis of cold type autoimmune Hemolytic anemia?
Anemia, mild jaundice, spleenomegaly, acroyanosis (purplish skin discolouration)
Morphology of cold type autoimmune Hemolytic anemia?
Clumping of RBCs , hazy blood film
Morphology of glucose 6phosphate deficiency
Heinz bodies and blister cells
Morphology of Thalassemia
Microcytic, hypochromic, target cells with central dark stain
Which thalassemia anemia is more severe? Minor or major?
Clinical features of thalassemia major
Severe anemia, spleenomegaly and liver Englarement, expansion of bones
What is sickle crisis
A sudden Severe attack of vascular occlusion, Hemolytic or marrow failure
What are folate and vitamin B12 required for
Synthesis for DTMP which is essential for DNA synthesis of thymine
Compare iron deficiency lab results to anemia of chronic disease
IDA has low ferris, ACD has high ferritin. Iron deficency has high TIBC , ACD has low TIBC
What are thalassemias?
Defects of globin destruction - alpha or beta
What happens in G6PD?
Hemolysis of RBC because of oxidative stress. This occurs because without G6P, NADH moron the Pentose phosphate pathway is decreased
And glutathione can no longer be produced. Glutathione assists with alleviating. oxidative stress
Causes of G6PD?
Infection, fava beans, anti malarial drugs
Clinical features of G6PD
Jaundice, dark urine, SOB, rapid HR
How does the direct Coombs test work
Detect antibodies Bound directly to RBC