News from Donor Hemovigilance: Grading Severity of Blood Donor Adverse Events Tool
Continuing the series of interviews with notable hemovigilance experts, we bring to you an interview with Mary J. Townsend, MD. Townsend serves as the senior medical director, National Office at Vitalant in Scottsdale, Ariz. She spent her career focusing on the care of donors, for whom she has an abiding passion. She was an inaugural member of the Uniform Donor History/HPC Task Force, serving as its second chair. She chaired both America’s Blood Centers’ Scientific, Medical, Technical and Quality Committee and the ABC Donor Adverse Event Committee. She has been a member of the AABB Donor Hemovigilance Working Group since its inception and was involved in one of three centers to pilot the Donor Hemovigilance Analysis and Reporting Tool, or DonorHART. She has been an editor of the Notify Library since 2015, focusing on donor adverse events and infectious events in recipients.
AABB: There was a session during the 2018 AABB Annual Meeting regarding the new donor severity grading tool developed by a sub-group of the AABB Donor Hemovigilance Working Group. Could you explain briefly what this project, Grading Severity of Blood Donor Adverse Events Tool, is all about?
Mary J. Townsend, MD: The AABB Donor Hemovigilance Working Group was very involved in establishing definitions of donor adverse events as a way to start talking about and measuring rates of such adverse events. The establishment of definitions of donor adverse events did not take place in a vacuum; we had international members on the task force, as well, to be sure that our definitions would translate to our global partners. Once the document was approved, it was modified by the International Society for Blood Transfusion (ISBT) and by the International Hemovigilance Network (IHN). Following adoption and publication of the definitions in 2014, many United States and international blood collection agencies began using these definitions to start gathering hemovigilance data. In addition, a validation study was performed to see how consistently these definitions were being used. Thirty test cases were evaluated, and the results of that validation study were recently published in Transfusion. One thing we learned from the validation exercise was that while the use of the adverse event definitions was fairly consistent, the assignment of severity of reactions was not, likely because of the subjective nature of severity. We saw a need to go a step further and develop severity definitions, and, hence, the work of this group began in January of 2018.
What was the impetus for this project?
As I just discussed, it was obvious from our validation study that we needed specific definitions to use in assigning severity to cases. In addition, because the assignment of severity is subjective, we needed a more objective way to make such assignments. Finally, there is a practical consideration that is also a legal issue. Using commonly used terms such as mild, moderate and severe could lead to legal action against a blood collector if a donor had an adverse event that was considered “severe.” Our approach called, instead, on a standard set of severity grading definitions that are used for many medical adverse events, such as reactions to medications, adverse outcomes of surgery and other medical procedures and conditions. A great example is the Common Terminology Criteria for Adverse Events, version 5.0, published by the U.S. Dept of Health and Human Services and the National Institutes of Health’s National Cancer Institute in November 2017.
What was some of the feedback that you have received to date, both during the 2018 AABB Annual Meeting and from international experts?
So far, we have received much positive feedback from our session at the AABB Annual Meeting, where we allowed participants to actually use the Severity Assignment Tool to designate severity in a number of test cases presented in the session. In addition, the Severity Assignment Tool has been sent to members of the international community through presentations at the ISBT and the IHN. In addition to some positive feedback, we have received some great recommendations for how to make the tool more user-friendly.
How are you incorporating all the feedback?
We have taken the feedback and recommendations back to the Working Group to modify some of the definitions and to clarify use of the Tool. As soon as we complete our validation testing phase, we will also incorporate appropriate changes into the tool.
What are your next steps for this project?
More than 30 test cases have been prepared from real world cases of donor adverse events. These were initially tested using our core group at the AABB Donor Hemovigilance Working Group, and modifications were made to the test cases to clarify them. These cases will be posted on the AABB website, and we will be asking any interested AABB members to complete severity assignments to the cases online
. This should be easy for members to do. At the same time, we will publish the link for global members and members of the ISBT and the IHN, asking them to do the same. We are also planning on sending an email invitation to eligible AABB members. The study will be conducted through Feb. 28, 2019.
Who is eligible to participate in the validation study?
Any AABB member will be eligible, but we will be most interested to hear from physicians, nurses and donor care staff of blood collection facilities, who will be using the tool when it is finalized. The same applies to our global partners. We really want a lot of feedback in order to make this the best tool possible.
Is there any message or heads-up that you would like to provide to our readers?
We encourage blood collection facilities to continue their efforts in donor hemovigilance. If you aren’t already gathering data, we encourage you to start, and we hope that the tools developed for your use will assist in that important task.
A sample case for the validation study.
Pre-Meeting Workshop on TACO, TRALI and TAD
Pulmonary transfusion reactions — transfusion-related acute lung injury (TRALI), transfusion-associated circulatory overload (TACO) and transfusion-associated dyspnea (TAD) — are some of the most serious transfusion reactions that can occur. A better understanding of how and why they occur could lead to better recognition, evaluation and differentiation of these reactions, not only for clinical and research purposes but also for hemotherapy surveillance. AABB held a pre-conference symposium on TACO, TRALI and TAD on Friday, Oct. 12, a day before the 2018 AABB Annual Meeting began. The meeting was sponsored by AABB, the ISBT and the IHN. The meeting’s goal was to highlight the current state of the research on these critical issues.
During the day-long symposium, experts reviewed evidence-based research on the etiopathogenesis, early recognition, management/mitigation guidance and hemovigilance practices related to these adverse pulmonary transfusion reactions. In addition, sessions covered the pathophysiological differences between the three reactions for clinical, research and hemovigilance surveillance purposes. There was also a discussion about proposed changes related to the surveillance definitions for TACO and TRALI. Clinical perspectives were provided from a cardiology, pulmonology and anesthesiology viewpoint. Insights from Canadian, United Kingdom and U.S. hemovigilance systems helped explain the current surveillance activities around these pulmonary transfusion reactions. Speakers also acknowledged that research questions around TAD have not yet been fully explored. There was a general agreement among the session attendees that there is a dearth of research activities on pulmonary transfusion reactions among the pediatric population.
AABB Announces Revised Zika Virus Biovigilance Network
The Zika Virus Biovigilance Network, a collaboration between AABB and U.S. blood collection establishments, was initiated in 2016. The Network contains collection and reporting data for donors with suspected Zika virus (ZIKV) infection and maps this data to geographical locations. AABB is pleased to announce the release of a revised version of the AABB Zika Virus Biovigilance Network that reflects the latest recommendations from the Food and Drug Administration’s July 2018 guidance, “Revised Recommendations for Reducing the Risk of Zika Virus Transmission by Blood and Blood Components
.” The guidance supports “…the use of mini-pool nucleic acid testing (MP-NAT) as a strategy to adequately and appropriately detect early infections in an outbreak, while reducing the burden of individual-donor (ID)-NAT testing.” It recommends switching from MP NAT to ID NAT in conjunction with available surveillance data (CDC and state or local health departments) to mitigate the risk of delayed recognition of ZIKV transmission through blood donors. The guidance also recommends that “…blood establishments that collect in the same geographic area develop a standard operating procedure (SOP) to communicate such ZIKV-reactive results with other blood establishments in that same geographic area and public health jurisdictions within 24 hours.”
The revised Zika Virus Biovigilance Network will allow blood centers and test labs that use MP NAT tests to report a reactive case once a reactive MP is resolved using ID NAT to identify the unit(s) that led to the reactivity of the MP sample. Users can report the presence or absence of alternate exposure (travel or sexual contact) for reactive donors and have the capability to update the status once the investigation is complete.
Once the pertinent data is entered into the Network, a Zika Virus Alert is simultaneously emailed to blood centers and testing laboratories in the Network. When a case is updated to indicate the exposure status (no alternative exposure/travel/sexual contact), an email update is sent to Network users. Each case can be identified by a unique AABB case number. This alert system was created to aid in the establishment of uniformed triggering and de-triggering criteria for ZIKV and to reduce the residual risk of ZIKV transmission through blood transfusions. The Zika Virus Biovigilance Network User Guide
and reports from the program have also been updated to assist blood centers utilizing this reporting/notification system to update their SOPs to fulfill the communications recommendations outlined in the FDA Guidance. For more information please visit our website
U.S. Map: ZIKV reactive blood donors by postal code. Nov. 27 - Dec. 27, 2018.
Common Transfusion Reaction Reporting Form, FAQ Resource Now Available
A new version of the Common Transfusion Reaction Reporting Form and a frequently asked questions (FAQs) resource are available for use on the AABB Hemovigilance web page
. The AABB Patient Safety Organization Advisory Committee and the AABB Donor Hemovigilance Working Group developed the form to help hospitals and blood centers communicate information about adverse transfusion reactions to the blood supplier, particularly when there are multiple suppliers. The AABB Hemovigilance web page also provides a feedback survey
link for hospitals and blood centers either already using the form or in the process of adopting it.
A portion of the Common Transfusion Reaction Reporting Form
Hemovigilance Module Updates
The National Healthcare Safety Network’s (NHSN) Hemovigilance Module, as part of the NHSN Release 9.2 on Dec. 8, 2018, has following updates:
- Addition of transitional patient blood types.
- Updates to the Transfusion-Transmitted Infection (TTI) portion of the algorithm that generates designations.
- Removal of error messages that occur at inappropriate times.
- Auto-population of facility characteristics in annual facility survey.
- Removal of annual transfusion summary from the annual facility survey.
A 13-year-old African-American male with sickle cell disease and on chronic red cell exchanges came to the pediatric ward for his monthly exchange on Oct. 1. His blood type was A RhD+, and he had always tested the same way. He received an exchange of six units of cross-match compatible packed red blood cells. He tolerated the procedure without incident. On Oct. 23, samples were sent to the blood bank for a new type and screen. A new anti-D and a positive direct antiglobulin test (DAT) were discovered. He has not received any other transfusions in the interim or been to any other facilities for medical care. He remembers being told something about having a “weak antigen” but does not remember the details. There was no evidence of hemolysis on laboratory workup , and the patient reports that he is in his usual state of health with no complaints. He received his monthly red cell exchange a few days later with RhD-negative cells that were also matched for C-E-K.
Adverse Reaction: Delayed serologic transfusion reaction (DSTR)
Case Definition: Absence of clinical or laboratory signs of hemolysis and demonstration of new, clinically-significant antibodies against red blood cells
Severity: Not Determined — Since this is by definition a reaction with no clinical symptoms, the severity of the reaction cannot be graded.
Imputability: Definite — New alloantibody is identified between 24 hours and 28 days after cessation of transfusion, and transfusion performed by your facility is the only possible cause for seroconversion.
As a follow-up, the patient was genotyped and found to have a weak-partial-D variant. Sickle cell patients often have RHD and RHCE gene variations which may account for as many as a third of allo-anti-D in patients with partial-D who develop antigens against the missing epitopes. RHD and RHCE have an opposite orientation and as much as 95% homology, creating a great deal of heterogeneity in antigen expression. Numerous gene rearrangements have occurred in African populations that result in partial antigens that contribute to the high rate of Rh alloimmunization among patients with sickle cell disease. As many as 10% of individuals with a “weak” D phenotype are actually partial-D when genotyped. Therefore, molecular follow-up should be provided when available, and patients must be treated as RH D negative until the testing is complete.
Case study credit: Sarah Vossoughi, MD, Columbia University Irving Medical Center & New York-Presbyterian Hospital
NHSN DSTR Data Entry Recommendation
- When a patient undergoes seroconversion and shows new clinically-significant antibodies to red blood cells within 28 days of transfusion, NHSN recommends using the date and time of testing to represent the date and time of reaction for DSTR.
- Time of reaction can be selected as “unknown” if the time of testing is unknown.
- If the patient exhibits seroconversion to more than one antibody, NHSN recommends reporting discovery of each new antibody as a separate DSTR.