Tag: Immunohematology

Immunohematology testing and processes

Summary of Accomplishments at Hamad Medical Corporation 2011-2020

drzeyd

2011

Established automated component production using Atreus technology, plasma and platelet pathogen inactivation (Mirasol)—made HMC component production Good Manufacturing System GMP compliant

2011

Qatar is the first to adopt non-PCR-based NAT technology (Grifols/Novartis Tigress) and becomes world reference site for this

2011

Based on the above, Qatar can now completely process all whole blood into blood components (red cells, platelets, and plasma) in as little as 5 hours from collection!

2011-2020:

I established policies and procedures for the hospital blood banks/transfusion services, blood donor center, therapeutic apheresis, and laboratory information systems to bring HMC in compliance with the Council of Europe, international AABB, and other standards.  I customized our own standards for our local needs based on them.

2012-2013

Implemented custom build of the multilingual blood bank computer system (Medinfo) for both patient and donor services, including development of interfaces to all production equipment including Atreus and Mirasol (world’s first) and a direct link to Ministry of the Interior to obtain patient demographics in English and Arabic—Qatar became the world’s first site to combine fully-interfaced, automated component production with pathogen inactivation:  Qatar becomes world reference site for this.

2013-2014

Built, validated, and implemented laboratory build of hospital information system, Cerner Millennium

2015

Replaced and updated Atreus with Reveos automated component production to allow faster throughput and capacity with a full bidirectional interface (world’s first), introduced platelet

additive solution PAS with pathogen inactivation (Mirasol)—Medinfo interfaces updated to Reveos for all equipment:  this doubles the capacity to process whole blood into components using the same physical space

2015-2019

Updated dedicated blood bank software Medinfo Hematos IIG by several versions using Division Head, LIS, and internally trained Super Users—at great cost savings to HMC by not using outside consultants (e.g. Dell Consulting)

2019

Established column absorption technology using Terumo Optia therapeutic apheresis machine for treatment of ABO-incompatible renal transplants:  I validated using the Ortho Vision MAX to perform ABO antibody titers for this system and correlated it with the reference method at Karolinska Institutet in Stockholm (manual gel) to bring rapid throughput and labor savings—Qatar being the first-site in the world to do this.  We saved money by using the same apheresis machine to use this column absorption technology (no need for second machine to use the columns)

2020

Expedited setup (two weeks total) of COVID-19 convalescent plasma production, initially manual and then fully integrated into the Medinfo computer system as a customized module with separate quarantine collection, production, and transfusion service functions

Other:

I was awarded two HMC Star of Excellence Awards:

2013—Liver Transplantation Transfusion Support

2019—ABO-Incompatible Renal Transplantation Support

Physicians and RBC Antibodies

drzeyd

During my career, the role of the transfusion medicine physician in handling RBC antibodies has evolved.  Depending on your location, either a specific transfusion medicine physician or a hematologist covering the specialty handled this.  In the United States, most hematologists nowadays do not do this.

During my US residency training in pathology, most trainees did not have an interest in blood banking and often used the rotation to take vacations.  For their board certification in clinical pathology, they crammed for the examination and afterwards did not engage in it.

When I started my career in the United States, hospitals had a hospital blood bank/transfusion service and handled most of their antibody problems themselves.  In Chicago where I practiced, many blood banks had Specialist in Blood Banks SBB graduates or SBB students working, and of course, they had a dedicated blood bank supervisor.

Currently in the United States, the hospital blood banks may be staffed by generalists and there is no one with specific antibody experience.  SBB graduates are expensive and usually work in blood centers or academic hospitals.

If you have a regional blood center with a reference laboratory, you can send your antibody workups there and let the blood center select appropriately antigen-matched units.  The physician covering the blood bank does not have to get very involved.

In the Middle East in the systems that I have run, there have been no reference laboratories and often no regional blood center.  The hospital system or the free-standing blood bank is an independent entity and must rely on itself.  The physician responsible for the blood bank must review the antibody panels and make his own decision how to select RBC components.

In the Middle East, especially in the larger centers with academic hospitals, there is usually a transfusion medicine physician who reviews the antibody workups and makes the final decision of what RBC types to dispense.  He does not have a reference laboratory to rely on.  He is responsible for the choices and has no one to refer cases on a 24/7 basis.

In the Middle East, the transfusion medicine physician must be proactive.  He must also select antigen-matched, fully or partially, and understand the trade-offs in cases with multiple antibodies.  He must know how to deal with nonspecific antibodies and antibodies to high-incidence antigens, especially if he works in a region where the antibody panels are not optimized to the local population or there are many different ethnic groups in the local area.

Thus, training someone to practice in the Middle East requires spending considerable time in technical matters that might not be necessary if he/she practiced in the West.  He may not only have to serve as a physician but he may be the equivalent of the reference laboratory supervisor.  Until such time that reference laboratories are available, this model is essential for safe practice.  Training programs for the region must reflect this and in particular, teach about specific antibodies common to the region.  He must be technically oriented and he must take ultimate responsibility for the interpretation of the antibody workups and selection of the appropriately matched units.

Electronic (Computer) Crossmatch

drzeyd

This is a revised version of a previous post.

As much as 90% of the RBC component allocation can be performed without an actual crossmatch test (AHG or immediate-spin) provided that certain criteria are met.

Enforcing these rules, however, can be cumbersome unless one has blood bank software that verifies that each rule is met.  In the Medinfo patient module, the transfusion history database is checked automatically.  If the rules are met, then Medinfo allows the selection (allocation) of RBC units without performing a crossmatch test.  Otherwise, it will check to see if the AHG crossmatch has been done within the past 3 days.  If not, it will prompt for new crossmatch testing with a new specimen.  If the situation is urgent, one can go to Emergency Mode and release components without the crossmatch.

Principle:

In selected patient categories, no classical crossmatch may be required for release of RBC components.  The criteria are specified here as applicable in my build of the Medinfo Hematos IIG computer system HIIG.

Policy:

  1. An electronic crossmatch without antiglobulin or immediate-spin phase testing may be used for the following patient categories:
    1. The current ABO/D type matches the historical ABO/D type.
    2. The ABO/D type (forward and reverse) is clearly defined without any discrepancies.
    3. Two determination of the ABO/D group must be made:
      1. One from a current specimen (within the past 72 hours)
      2. The second by one of the following methods:
        1. Testing a second current specimen
        2. Comparison with previous records of ABO/D typing
        3. Retesting the same specimen
    4. The current antibody screen is negative
    5. There is no history of RBC antibodies or a non-negative antibody screen.
  2. If the criteria in #1 are not met, the AHG crossmatch is required in non-emergency situations.
  3. General computer system safeguards:
    1. The system contains the donor unit number, component name, confirmed ABO/D typing, two unique recipient identifiers, recipient ABO/D, antibody screen typing, and interpretation of compatibility
    2. A method exists to verify correct entry of data before release of blood or blood components.
    3. The system contains logic to alert the user to discrepancies between donor ABO/D group on the unit label and those determined by blood confirmatory tests and to ABO incompatibility between the recipient and donor unit.
  4. HIIG will enforce the above rules.

References:

  1. HIIG Workflow 1004, Patient Testing, Latest Version
  2. Section 5.16, Standards for Blood Banks and Transfusion Services, Current Edition, AABB, Bethesda, MD, USA
  3. FDA Guidance for Industry:  Computer Crossmatch (Computer Analysis of the Compatibility between the Donor’s Cell Type and the Recipient’s Serum or Plasma Type), April, 2011

DAT and Selection of RBC Units for Transfusion

drzeyd

This is an update of a previous post.

Principle:

In 1984 effective with the 13th Edition AABB Standards, the requirements for performing a direct antiglobulin test and autocontrol for compatibility testing were eliminated.  The DAT is very important to detect delayed hemolytic transfusion reactions, certain autoimmune conditions, and drug-related hemolysis.

Since that time, the immediate-spin crossmatch and now the electronic computer paperless crossmatch may be used for most compatibility testing in place of the classic, antiglobulin-phase (indirect antiglobulin test) crossmatch.

If an antiglobulin phase (IAT) crossmatch is performed, an RBC unit with a positive DAT will cause a false-positive reaction.  Since most crossmatching does not include the IAT, it will not be affected by the DAT status of a donor unit.

Policy:

  1. Donor RBC units will NOT be routinely tested for DAT as part of component processing.
  2. The type of compatibility testing selected for a particular patient should be the technically simplest one (no need to do extra work unless so instructed by the transfusion medicine consultant/designate):
  3. Do a full antiglobulin-phase IAT crossmatch if ANY of the following applies:
    1. There are no two independent ABO/D typings on the patient during the current admission.
    2. The ABO/D type of the current admission does not match the historical information.
    3. The patient has a detectable antibody at 37C
    4. The patient has a history of a clinically significant antibody but no current antibody
    5. Whenever the consultant, transfusion medicine/designate requests it.
    6. Whenever the Medinfo HIIG record so indicates (in comment section)
  4. Do the immediate-spin crossmatch if ALL of the following apply:
    1. Only one determination of the ABO/D type
    2. The historical ABO/D type agrees with the current type.
    3. There are no antibodies reacting at 37C AND there is no history of antibodies at 37C.
  5. Use the computer/electronic crossmatch if ALL of the following apply:
    1. There are two determinations of the ABO/D type and they both agree with each other.
    2. The historical ABO/D type agrees with the current type.
    3. There are no antibodies reacting at 37C AND there is no history of antibodies at 37C.
  6. When to do a DAT on a donor unit:
    1. Patient antibody screen is negative but the full AHG crossmatch is incompatible.
    2. Part of a transfusion reaction workup where the AHG crossmatch of donor cells and patient serum is incompatible.
    3. Whenever the consultant, transfusion medicine/designate requests it.
  7. If a donor unit is found with a positive DAT:
    1. Required testing and review:
    2. Test with polyspecific and monospecific IgG and C3d antisera
    3. Perform an acid-elution.
    4. Send the results to the transfusion medicine consultant/designate for review.
    5. The reviewer will enter his review in HIIG in the Donor Consultation Section both as global donor comment and a result-specific comment against the antibody screen result.
    6. Use of the DAT-positive donor unit:
      1. Most of the time you will not know if the donor RBC unit is DAT-positive since we mainly use the electronic crossmatch.  It will be used if all criteria are met.
      2. Otherwise, select another RBC unit for the AHG crossmatch.
      3. The final decision to use the DAT-positive unit will be made by the Transfusion Medicine consultant/designate.

Important:  Don’t do a classic AHG/IAT phase crossmatch unless you have to do it  (see conditions above.)  A donor unit with a DAT is unlikely to be clinically significant and may be transfused safely to the patient in most situations.  Patients receiving electronic-crossmatch and immediate-spin crossmatch are receiving units with positive DAT without incident.

References:

  1. Standards for Blood Banks and Transfusion Services, Current Edition, AABB, Bethesda, MD, USA
  2. Guidelines to the Preparation, Use, and Quality Assurance of Blood Components, European Committee (Partial Agreement) on Blood Transfusion (CD-P-TS), Current Edition
  3. Technical Manual, Current Edition, AABB, Bethesda, MD, USA, 2012