When ABO antigens membrane bound?
RBCs
Platelets
VASCULAR ENDOTHELIUM (all vessels including organs)
Epithelial surfaces
What is the most common presenting symptom of transfusion reaction?
FEVER!
Also see: chills, hives, respiratory distress
What is the most antigenic blood group antigen next to ABO? Why?
Rh antigen (D antigen)
Because there are fewer IgG antibodies in ABO (less cross the placenta)
What blood group antigens are well known for causing amnestic response? and intravascular hemolysis?
Kidd Blood Group
Antigens: Jka, Jkb, and Jk3
One of few IgG antibodies that can cause intravascular hemolysis
Antibodies can disappear, not be detected at time of testing
What is the number one cause of transfusion related fatality?
Transfusion related acute lung injury (TRALI)
Risk of transfusion transmitted HIV?
1 in 2,135,000
Most common infectious complication of a transfusion?
Bacterial contamination
Causes of respiratory distress associated with transfusion?
- Transfusion associated circulatory overload (TACO)
- Transfusion related acute lung injury (TRALI)
- Hemolytic Transfusion reaction
- Transfusion associated sepsis
- Anaphylactic/Anaphylactoid reactions
- Coincidental underlying condition
Difference between primary and secondary erythrocytosis/polycythemia?
Primary = independent of EPO (malignancy)
Secondary = due to high EPO (anything causing decreased O2 to tissues will increase EPO
Smoking increases EPO without causing hypoxia
What can cause a discrepancy between Hgb and HCT?
Hbg x 3 should = HCT
If Hbg x 3 - HCT > +2 then…
free Hgb
Interference/Artifact
Red cells are sticking together
**Artifact can be caused by opacified plasma, high bilirubin, high triglycerides
*NOTE: RBC count is not affected by this
Low MCHC usually means?
Hypochromic = decreased Hgb in RBCs = decreased production of Hbg or heme
(Often due to iron deficiency)
Which of the following patient lab profiles IS NOT consistent with ANEMIA?
A. Increased RBC; decreased Hgb; decreased MCV; normal HCT
B. Normal RBC; decreased Hgb; decreased MCV; normal HCT
C. Increased RBC; normal Hgb; decreased MCV; normal HCT
D. Decreased RBC; normal Hgb; increased MCV; decreased HCT
E. Decreased RBC; increased Hgb; normal MCV; decreased HCT
Answer = C
Which of the following IS NOT associated with bone marrow erythroid hypoplasia (decreased red cell precursors in bone marrow)? A. Fanconi anemia B. Diamond-Blackfan syndrome C. Vitamin B12 deficiency D. Radiation toxicity E. Viral infection
C. Vit B12 deficiency (considered ineffective bone marrow production of mature RBCs)
What is the difference between Thalassemia and Hemoglobinopathy?
Thalassemia =inherited disorder where there is impaired or absent transcription of one or more globin
Hemoglobinopathy = A mutation in a globin gene that results in production of mutant globin protein which can form an abnormal tetramer (example= mutant bs gene transcribes mutant S-globin which forms tetramers to create sickle hemoglobin)
Low RBC Low MCV Low MCHC High RDW Low ferritin High transferrin Low Fe Sat
Iron deficiency anemia
High Ferritin
Decreased transferrin
Normal Fe Sat
Anemia of chronic disease (normal iron sat cuz transferrin is also decreased)
would have high hepcidin assay
What does a VERY low transferrin level indicate?
Chronic inflammatory state- likely has some component of ACD
What is sideroblastic anemia?
Enzymatic defect in heme biosynthesis - accumulation of iron around nucleus
Very high ferritin Normal transferrin Normal Iron Sat Normal Sat Normal hepcidin
Sideroblastic Anemia
What are hemoglobin bars?
An unstable tetramer made up of 4 gamma globins; seen at birth when there are any (1, 2, 3 or 4) alpha globin genes deleted
What are hemoglobin H?
An unstable tetramer made up of four beta globins, present in very small amounts in people with Hemoglobin H disease (3 alpha genes deleted)
Barts on newborn screen
Normal Hb ELP
Normal CBC
Alpha Thal Trait (1 alpha gene missing)
Barts on newborn screen
Normal Hb ELP
Low MCV w/out anemia
Alpha Thal Minor (2 alpha genes missing)
Barts on newborn screen
Trace Hgb H detectable on Hgb ELP
Lifelong microcytic hemolytic anemia
Hemoglobin H (unstable B tetramers)
3 alpha globin genes missing
High HgA2 would indicate what?
Beta Thalassemia
Would see increase in A2 at 6 months of age
No Hgb A (2 alpha, 2 beta) detected on Newborn screen! All Hgb F (2 alpha, 2 gamma)
How long should you wait after a transfusion to interpret Hgb electrophoresis?
3 months!
What do things can lead to excess unesterified cholesterol in circulation causing “too much membrane” and macrocytosis (with target cells)?
Liver disease
Hypothyroidism
What is a megaloblastic process?
Any situation where you can synthesize protein (cells can grow) but can’t synthesize DNA (thus cells can’t divide)
Can be caused by ETOH!
Major cause of thrombcytosis?
Asplenia (or functional asplenia)
Can see thrombocytopenia in spleen sequestration! (will have large spleen!)
LOW haptoglobin
High LDH
High bilirubin
Intravascular Hemolysis!
Your 22 year old female patient has a low haptoglobin level, an elevated LDH and elevated total bilirubin level which, when fractionated, is almost entirely indirect bilirubin. What further test(s) might you order first that could help you to distinguish between hemolysis and a megaloblastic anemia (such as vitamin B12 or folate deficiency)?
A. A bone marrow biopsy
B. A reticulocyte count and a blood smear for morphology
C. A urine pregnancy test
D. A fractionated LDH
E. An ethics consult.
Answer = B
Question on exam!
What 3 things can causes monocytopenia?
Aplastic Anemia
B-cell leukemia
Glucocorticoids
Test question!
Which of the following IS NOT associated with NEUTROPHILIA?
A.Acute bacterial infections.
B.Aplastic anemia due to total body irradiation.
C.Cigarette smoking
D.Lithium therapy
E.Steroid therapy
Answer B