Lewis Blood Group System: tangled web of Le, Se, H and ABO. First of all, remember that Type 1 precursor is found only in secretions. There is no type 1 on RBC surface, only Type 2.
Diego negative might be HE and HS (Band 3 deficiency)
Dialysis = anti-N.
Hard to remember shelf-lives. 1. Washed, thawed/deglycerolized RBC = 24 hours. 2. Thawed FFP = 24 hours (if not used after 24 hours, relabel as plasma). 3. Thawed plasma = 5 days. 4. Pooled platelets = 4 hours. 5. Thawed cryo, unpooled = 6 hours. 6. Thawed cryo, pooled = 4 hours.
INTRAvascular hemolysis = ABO, Kidd and P (PCH).
Antigens destroyed by enzymes: Duffy and MNS (Lu and Chido, too)
4 most common in HDN = anti-D, anti-AB, anti-Kell and anti-c.
Take Home Point 2. DOSAGE = Kidds and Duffy the Rh (CcEe, not D) Monkey eat lots of M&N.
Take home points 1. NATURALLY OCCURING ANTIBODIES = Lu, Le, M, N, O (AB), P (and I,i). These are also IgM (except for AB that cause HDN) and antibodies react at room temp.
Iron overload can be an issue. Each unit has 200 mg iron. When whole body iron burden exceeds 500mg/Kg, it can be a problem. Can chelate with desferroxamine.
Hypothermia is a risk with massive transfusion, so can pre-warm the products but cannot exceed 42C according to AABB.
Babesiosis = Ixodes tick (same as Lyme and erlichiosis) = risk is HIGH 1:1000! Screen with history.
Malaria (Anopheles mosquito). 1 in 4 million! Screened by history. I kind of thought you couldn't get disease via transfusion since you need to be bit by the mosquito= ask Tom.
RPR test is non-treponemal screen using latex agglutination (?). Screen in blood but confirmatory in CSF! Anyway, if you have syphilis, you have a VERY BRIEF period of bacteremia, which is really hard to catch with RPR since it only becomes positive later on. Also, most RPRs are false positives. SO, point is, this is used as a surrogate to test for high risk behavior.
HIV is 1:400,000 all the way up to 1:2,400,000. All screened by serology and nucleic acid testing.
Hepatitis C is lower risk: 1:800,000 to 1:700,000.
Infection Risk: Hep B is HIGHEST RISK at 1:100,000!
Platelet refractoriness. Multiple transfusions during chemo, usually occurs in 25% of AML patients. Have to rule out sepsis, DIC, drugs (amp), splenomegaly. Factors that increase risk multiple pregnancies, male gender, heparin, fever, bleeding, big spleen. HLA CLASS I (A and B) that are present on platelet surfaces. Most with true refractoriness show NO increase in platelet count. Platelet count increment (CI) = Posttransfusion platelet count - pretransfusion platelet count x BSA all divide...
PTP. Due to recipient being PLA1 negative, mounting a response to PLA1 positive platelets. 2% of population is negative, 98% has the antigen. This usually occurs in multiparous women and occurs 2-14 days after transfusion. WEIRD part is that the patient's own platelets are also destroyed even though they are antigen negative!! Treat with roids, plasma exchange to remove antibodies and IVIG.