Category: Patient

Includes compatibility testing (AHG, electronic, immediate-spin), antigen typing, antibody screening and identification, direct antiglobulin testing, elution, transfusion reaction and drug reaction workups, component typing tests upon receipt in hospital blood bank, release and return of components

Ortho D Typing Reagents for Patients

drzeyd

Policy:  Ortho Rh1 D Typing Reagents for Patients

Zeyd Merenkov, MD, FCAP, FASCP

Independent Consultant in Transfusion Medicine and Blood Bank IT

Revision Date:  21/3/18

Principle:

We must select D-negative RBC units for transfusion if the patient is truly D-negative or if he/she is a partial D since transfusion of a partial D positive unit may induce antibodies against any part of the D molecule.  Thus, for patients, we will consider patients with partial D as D-negative.  Note that this is NOT the usual practice in the USA;  however, AABB Standards do allow that we do NOT test patients for weak D and give D-negative RBCs instead.

Background:

Ortho Diagnostics Reagents use two different monoclonal antibody cocktails that react variably with the antigen D (Rh1)—these are found on the card:  Anti-A/B/A,B/D/D/Ctrl:

Anti-D/Anti-RH1—IgM monoclonal antibody clone D7B8 can detect most examples of weak and partial D including weak D types 1, 2, 3, 4.0, and D categories II, III, IV, V, VII, DBT, and R0Har.  It does NOT detect category VI.  Retest positive reactions of 2+ or less by an alternate method.

Anti-D/Anti-RH1—IgM monoclonal antibody RUM1 can detect most examples of weak and partial D including weak D types 1, 2, 3, 4.0, and D categories II, III, IV, V, VII, DBT, and R0Har.  It does NOT detect category VI.  Retest positive reactions of 2+ or less by an alternate method.

Policy:

  1. Follow the manufacturer’s instruction for storage, handling, and usage of all reagents.
  2. If the D-control is positive, the reactions are indeterminate, repeat by another method.
  3. Run both anti-D reagents listed—do not use the donor typing algorithm or reagents.
  4. Use the following table for interpretation and further actions if needed:
Pattern #Anti-D/D7B8Anti-D RUM1D-Interpretation
1PositivePositiveD-positive
2PositiveNegativeDo additional testing
3NegativePositiveDo additional testing
4NegativeNegativeD-negative  

If the reaction is 2+ or less with either the Ortho anti-D/D7B8 reagent or anti-D/RUM1 or if the patterns 2 or 3 above, repeat by another manufacturer’s reagents.  In the meantime, consider the patient as D-negative.

Medinfo-Ortho interface settings for Patient Testing in Hematos Medinfo IIG:

Anti-D/D7B8Anti-D RUM1D-Interpretation
3, 43, 4D-positive
3, 40~
03, 4~
00D-negative
~~~

Note all of the following:

  1. If the result is D-indeterminate, use D-negative RBCs.
  2. No reagents may be able to detect all D variants.
  3. ~ means any other value for that reagent (1+, 2+, mf, hemolyzed)
  4. Note that this new algorithm makes a 2+ reactivity as indeterminate with Anti-D/D7B8 or Anti-D/RUM1.

References:

  1. Publication e631300291, Product Insert, Anti-A/B/A,B/D/CDE/Control Card, 2010, Ortho Clinical Diagnostics, High Wycombe, Buckinghamshire/UK
  2. Standards for Blood Banks and Transfusion Services, Current Edition, AABB, Bethesda, MD, USA