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Interesting Case Studies from The Mayo Clinic Reference Laboratory

Interesting Case Studies from The Mayo Clinic Reference Laboratory . Georgette Benidt, MT(ASCP). Case 1. 81 year old with B-cell lymphoproliferative disorder Clinician ordered the Donath Landsteiner Test. DONATH-LANDSTEINER (DL). Case 1 – objectives. Significance of the test

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Interesting Case Studies from The Mayo Clinic Reference Laboratory

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  1. Interesting Case Studies from The Mayo Clinic Reference Laboratory Georgette Benidt, MT(ASCP)

  2. Case 1 • 81 year old with B-cell lymphoproliferative disorder • Clinician ordered the Donath Landsteiner Test

  3. DONATH-LANDSTEINER (DL)

  4. Case 1 – objectives • Significance of the test • Incidence of positive tests • Testing challenges

  5. DL Significance • Paroxysymal Cold Hemoglobinuria is an ideopathic disorder occurring in <1% of hemolytic anemias • IgG biphasic autoantibody (usually anti-P) • Fixes complement at 4 C • Activates complement at 37 C • Patient needs to avoid cold exposures (MN winters, air conditioners)

  6. Donath-LandsteinerTesting Challenges • Need to maintain the specimens and controls at 37°C. • Length of time from start to finish is minimum of 2 ½ hours • Need fresh donor samples for complement and RBC’s

  7. Case 2 • 68 Y.O. male • O Rh negative • Myelodyplasia Syndrome • Transfusion Dependent • Previous Anti-K, Anti-E, Warm Autoantibody • Presents now with the following results:

  8. Case 2: Initial Panel

  9. Case 2 • Do you see a pattern? • Is there varying reactivity? • We know that the patient has a warm autoantibody, what next? • At Mayo, we absorb onto 3 different cells: R1R1, R2R2, and rr

  10. Case 2: R1R1 Absorbate

  11. Case 2: R2R2 Absorbate

  12. Case 2: rr Absorbate

  13. Case 2 • What antibodies were identified: • Anti-G, Anti-C, Anti-E, Anti-K, Anti-Mur, Anti-V, and Warm Auto • Why do we care about underlying antibodies: • Possible DHTR • Difficulty of finding antigen negative blood

  14. Case 2 • What is significant about Anti-G? • Belongs to the Rh family • G antigen is present on all D+ and or C+ RBCs • IgG and does not fix complement • Stimulus from the transfusion of C+ RBCs following trauma

  15. Case 2 • More on anti-G • For Transfusion: • Provide D-, C- crossmatch compatible RBCs • For OB Patients • Adsorption/elution studies may be necessary to determine if anti-D is also present • RhIG administration??

  16. Case 2 • Antigen Incidence • Blacks • 92% • Caucasians • 84% • Asians • 100%

  17. Case 2: Conclusion • Anti-G has been shown to be present years after the exposure of D+ or C+ RBC’s • Why did we care in this case? • The patient had a previous Anti-C • The patient has only received Rh negative blood that we know of • Do we have a rr, G+ donor?

  18. Case 3 • 20 YO female • A Rh negative • 38 week gestation in 2nd pregnancy • No other information available • Initial panel results are:

  19. Case 3: Initial Panel

  20. Case 3 • Do you see a pattern? • What should be done next? • Why?

  21. Case 3 • Possible antibody to high incidence antigen • Perform phenotype • Test serum against phenotypically similar cell • If negative, look for multiple common antibodies • If positive, consider high incidence

  22. Case 3 • Our results • Phenotypically similar cell reacted 1+ with patient serum • Antibody was titered to determine if it exhibited HTLA characteristics • Antibody did not have a high titer • Now what?

  23. Case 3 • DTT and papain treated cells were tested • The antibody did not react with the treated cells. Antigen is assumed to be sensitive to treatments • A list of high incidence antigens was compiled

  24. Case 3 • Based on the sensitivity of papain and DTT, a Yt(a-) cell was thawed and tested • This cell was negative at AHG, and 2 more Yt(a-) cells were thawed and tested • We now have our 3 negative cells to confirm the presence of an Anti-Yta • The patient’s antigen status was Yta-

  25. Case 3 • In most populations, Yta has an antigen incidence of >99.8% • Yta can bind complement • Yta has been shown to cause anywhere from no transfusion reactions to moderate/delayed reactions • Yta has not been shown to cause HDN

  26. Case 4 • 26 Y.O. female • A Rh negative • Presented during pregnancy • No known antibody history • Patient presents now with the following results:

  27. Case 4: Initial Panel

  28. Case 4 • Possible Suspects • Multiple allo-antibodies • High-Titer-Low-Avidity • High Incidence

  29. Case 4 • Phenotype was performed • Phenotypically similar cell was tested against serum and reacted 1+ AHG. • Ruled out the common multiple alloantibodies. • What would you do next? • HTLA titers were done x2 with possible HTLA identified

  30. Case 4 • I was not convinced of the HTLA • HTLA negative cells (Ch,Rg,Kn,Mc) were run with similar results • We papain and DTT treated the same panel cell to see if we could rule out antigens • Papain cell still reacted • DTT cell did not react, and upon repeating, reacted at micro positive.

  31. Case 4 • Based on the Papain and DTT results, high incidence negative cells were tested • Lu(a-b-); Sc:-1,2; K null; Yt(a-); Ge:-2,-3; Lu:-8; Lu:-6 cells were all W+ • At this point, we decided to send it to New York Blood Centers to see if they could identify the antibody

  32. Case 4 • NYBC identified an Anti-Jra • We picked ourselves up, dusted off and confirmed these results with our own reagents.

  33. Case 4 • A little about anti-Jra (Junior) • Anti-Jra can bind complement • Can cause transfusion reactions but no cases of HDN have been identified • This antigen has an incidence of >99% in most of the population

  34. Case 4 • What went wrong? • Weforgot that antibodies do not read textbooks! • Jra antigen should be resistant to DTT • Anti-Jra antibodies shouldn’t look like HTLAs • Our patient wasn’t Japanese

  35. Case 4 • Outcome of patient: • Patient was urged to donate units while she was still pregnant in case she needed them • Baby was antigen positive, but there were no complications • Patient remains an allogeneic blood donor

  36. Conclusions • HTLA’s and High Incidence antibodies can mimic each other • High Incidence antibodies can titer out to HTLA levels • It is important to differentiate between HTLA and High Incidence antibodies • Certain patient populations will continue to form antibodies

  37. Conclusions • It is helpful to perform phenotypes, especially on patients you expect to have multiple transfusions • Tests that seem like a waste of time can sometimes surprise you! • Remember to take a picture of a positive DL…you may never see another one.

  38. References • The Blood Group Antigen Facts Book, M.E. Reid, C.L. Francis • Applied Blood Group Serology, P.D. Issitt, D.J. Anstee • Technical Manual, 15th edition • Mayo Clinic Transfusion Medicine SOP’s

  39. Thanks • Craig Tauscher for helping me prepare this presentation • Sheila Muenster for reviewing my presentation • The MT students who had to sit through my rough draft • Bob Stowers for having the DL • The rest of my coworkers for their help

  40. Any Questions??

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