MMSC 420 Exam 3 Questions with Correct Answers Graded A+
Anti-M - Answers -usually not significant
-pregnant females if reacting at 37C- then may be significant
Anti-N - Answers -not clinically significant
-more rare than anti-M
-renal patients with dialysis on machines cleaned with formaldehyde may exhibit anti-N
Anti-S, and Anti-s (little) - Answers -not clinically significant
-can be IgM, but mostly IgG
-enhanced by decreased temp
-transfusion reactions no to rare
-HDFN no to severe
Anti-P1 - Answers -usually not clinically significant
-primarily IgM
-enzymes enhanced highly
-transfusion reactions (no to moderate/delayed but rare)
-HDFN- NO
Antibodies in the MNSs and P1 (and Lewis) - Answers Pre warm technique
-use when a cold reactive antibody is present- use with care
-great for removing cold autoantibodies in lieu of an adsorption
-not recommended for patients who have been transfused in the past 3 months (you may miss
newly forming IgM antibodies)
Run prewarmed AB screen/panel - Answers -weak reactions mixed with stronger reactions
-no obvious specificity
-need to evaluate/eliminate weak cold AB
Prewarmed Procedure - Answers -everything warmed to 37C initially
-label all tubes
, -using 2 drops of prewarmed serum, place 1 drop of prewarmed RBCs
-check with SOP to determine if/which enhancement media (warmed) to use and determine
incubation time, usually NO enhancement and 30-60 min incubation
-after incubation, wash 3 to 4 times with WARM saline
-add AHG reagent, centrifuge and read
-check all negative reactions with check cells
I/i blood group - Answers -at birth I ag is low and i ag is high
-at >18 months I ag is high and i ag is low
Auto anti-I - Answers -adult RBCs (++)
-cord blood cells (-/little)
-4C incubation (++)
-enzyme treated cells (++)
-M. pneumonia infection increased auto-anti-I
Auto anti-i (little) - Answers -adult RBCs (-/little)
-cord blood cells (++)
-4C incubation (++)
-enzyme treated cells (++)
-very rare- infectious mononucleosis
Remember I/i blood group - Answers -history: no previous transfusion or no transfusion within
past 3 months
-DAT is usually positive with polyspecific AHG and anti-C3bC3d reagents (negative with Anti-IgG)
-causes? may be mycoplasma pneumonia infection, infectious mononucleosis, cold agglutinin
disease
I/i may have forward/reverse group issues- reactivity that is unexpected - Answers -EX. forward
types as AB, reverse types as O (everything is pos)
-may need to wash cell suspension with warm saline, prewarm cells before addition of reagents
-may need to prewarm reverse group cells and plasma, then add together and spin/read quickly
Anti-M - Answers -usually not significant
-pregnant females if reacting at 37C- then may be significant
Anti-N - Answers -not clinically significant
-more rare than anti-M
-renal patients with dialysis on machines cleaned with formaldehyde may exhibit anti-N
Anti-S, and Anti-s (little) - Answers -not clinically significant
-can be IgM, but mostly IgG
-enhanced by decreased temp
-transfusion reactions no to rare
-HDFN no to severe
Anti-P1 - Answers -usually not clinically significant
-primarily IgM
-enzymes enhanced highly
-transfusion reactions (no to moderate/delayed but rare)
-HDFN- NO
Antibodies in the MNSs and P1 (and Lewis) - Answers Pre warm technique
-use when a cold reactive antibody is present- use with care
-great for removing cold autoantibodies in lieu of an adsorption
-not recommended for patients who have been transfused in the past 3 months (you may miss
newly forming IgM antibodies)
Run prewarmed AB screen/panel - Answers -weak reactions mixed with stronger reactions
-no obvious specificity
-need to evaluate/eliminate weak cold AB
Prewarmed Procedure - Answers -everything warmed to 37C initially
-label all tubes
, -using 2 drops of prewarmed serum, place 1 drop of prewarmed RBCs
-check with SOP to determine if/which enhancement media (warmed) to use and determine
incubation time, usually NO enhancement and 30-60 min incubation
-after incubation, wash 3 to 4 times with WARM saline
-add AHG reagent, centrifuge and read
-check all negative reactions with check cells
I/i blood group - Answers -at birth I ag is low and i ag is high
-at >18 months I ag is high and i ag is low
Auto anti-I - Answers -adult RBCs (++)
-cord blood cells (-/little)
-4C incubation (++)
-enzyme treated cells (++)
-M. pneumonia infection increased auto-anti-I
Auto anti-i (little) - Answers -adult RBCs (-/little)
-cord blood cells (++)
-4C incubation (++)
-enzyme treated cells (++)
-very rare- infectious mononucleosis
Remember I/i blood group - Answers -history: no previous transfusion or no transfusion within
past 3 months
-DAT is usually positive with polyspecific AHG and anti-C3bC3d reagents (negative with Anti-IgG)
-causes? may be mycoplasma pneumonia infection, infectious mononucleosis, cold agglutinin
disease
I/i may have forward/reverse group issues- reactivity that is unexpected - Answers -EX. forward
types as AB, reverse types as O (everything is pos)
-may need to wash cell suspension with warm saline, prewarm cells before addition of reagents
-may need to prewarm reverse group cells and plasma, then add together and spin/read quickly
