Stephens, Laura D.

Abstract Background and Objectives Cryoprecipitated antihemophilic factor (cryoprecipitate), fibrinogen concentrate (FC), and pathogen‐reduced cryoprecipitated fibrinogen complex (PR cryoprecipitate) are sources of fibrinogen replacement, and each has advantages and disadvantages in terms of cost, efficacy, safety, and logistics of administration. This study examines the respective utilization frequencies of these different products at institutions in North America and the factors influencing the decision on which one(s) to adopt. Materials and Methods A survey was distributed via email to contacts for Advancement of Blood and Biotherapies (AABB)‐accredited blood banks/transfusion services. Survey questions covered topics including the availability and usage of FC, cryoprecipitate, and PR cryoprecipitate, as well as the perceived advantages of each product. Results A total of 53 responses were received from surveyed institutions (estimated 25% response rate). Over half (31/53, 58.5%) of respondents exclusively used cryoprecipitate, 30.2% (16/53) used two sources of fibrinogen replacement, and 7.5% (4/53) used all three (cryoprecipitate, FC, and PR cryoprecipitate). More than half of the institutions restricted FC to specific indications, primarily for cost containment. The most commonly cited advantages of FC over cryoprecipitate were storage convenience and rapid reconstitution. Conclusion Surveyed institutions in the United States and Canada primarily use cryoprecipitate for fibrinogen replacement, with variable usage of FC and limited usage of PR cryoprecipitate. The perception of FC being more expensive than cryoprecipitate predominated. Further studies comparing available fibrinogen replacement options would be valuable, particularly with consideration of product acquisition cost, wastage, impacts on utilization of other blood products, and patient outcomes.

Abstract Background Anti‐M antibodies were described as rarely eliciting hemolytic disease of the fetus and newborn (HDFN) in pregnancy. More recent literature, primarily from Asia, reports severe HDFN attributed to maternal anti‐M. The objective of this study is to determine if there is a difference in the frequency and/or severity of anti‐M HDFN among subjects who self‐report as Asian compared to non‐Asian. Methods Retrospective data were collected from 18 sites. Fetuses/neonates affected by HDFN were categorized as unaffected, mild, moderate, or severe based on clinical management and outcomes. Results Anti‐M was identified in 557 obstetric patients. Among 332 neonates with complete data for analysis, anti‐M was detected in isolation during the pregnancies of 210 (63.3%) neonates; 198 (94.3%) were unaffected by HDFN. The overall frequency of HDFN was 6.5% (2/31) in Asian patients and 5.6% (10/179) in non‐Asian patients. The frequency of severe HDFN was 6.5% (2/31) among Asian patients and 0.6% (1/179) among non‐Asian patients. Among non‐Asian patients, eight (4.5%) were mild and one (0.6%) was moderate. Of 63 pregnancies with anti‐M and ABO incompatibility, 6 (9.5%) were associated with mild HDFN and 57 (90.5%) were unaffected. Of 49 pregnancies with anti‐M and non‐ABO antibody(s), 6 (12.2%) were associated with mild HDFN and 43 (87.8%) were unaffected. One case (10.0%) of HDFN (mild) occurred in the presence of anti‐M, additional antibody(s), and ABO incompatibility. Conclusion In this study, severe anti‐M HDFN was rare in non‐Asian subjects. There is a signal that Asian patients are at greater risk for severe anti‐M HDFN.

ABSTRACT The American Society for Apheresis (ASFA) Attending Physician Subcommittee of the Physicians' Committee performed an annual review of articles published in 2024 related to apheresis medicine. The 10 seminal apheresis articles selected by the subcommittee members are summarized in this review. PubMed was used to identify manuscripts published in 2024 in four areas of interest: donor apheresis, therapeutic apheresis, apheresis education, and apheresis for cellular therapy. Only full length, peer‐reviewed manuscripts in English with data from human subjects were included. Case reports, review articles, and meta‐analyses were excluded. Articles were considered seminal if they met at least one of the following previously established criteria: novel finding(s), practice‐altering outcomes, international in scope, randomized‐controlled trial, relevant to current clinical practice, and/or provide evidence for category III or IV indications based on the ASFA 9th special issue of the Guidelines on the Use of Therapeutic Apheresis in Clinical Practice‐Evidence‐Based Approach.

Abstract Background Rh immune globulin (RhIG) is used to prevent D alloimmunization and reduce the risk of hemolytic disease of the fetus and newborn (HDFN). Its use has been expanded to include immunoprophylaxis after D‐incompatible transfusions. In the United States, a protracted RhIG shortage began in 2023. The AABB (Association for the Advancement of Blood & Biotherapies) Clinical Hemotherapy Subsection created a survey to assess RhIG usage patterns during this shortage. Methods A survey was developed and electronically distributed to AABB‐accredited institutions. The number of responses was tallied. Frequencies were calculated, and free text comments were categorized. Results A total of 112 responses (13.7%) were received from all regions of the United States. While 6.2% (6/97) of respondents noticed increased RhIG usage, 70.0% (56/80) experienced a shortage of RhIG. The most common indication reported for RhIG use was D‐negative pregnant patients carrying a D‐unknown or D‐positive fetus/neonate. Some respondents also permitted RhIG use in D‐negative adult males and females outside of childbearing age following D‐incompatible transfusion. The most common institutional responses to the shortage were to: formally monitor RhIG inventory ( n = 37), add ( n = 34)/switch ( n = 24) manufacturers, and redistribute RhIG between facilities ( n = 22). Few respondents ( n = 7) limited or discontinued RhIG use in non‐obstetric patients. Conclusions While the majority of survey respondents were affected by the RhIG shortage, transfusion services still allowed RhIG to be issued outside of obstetric care. Given that RhIG is a limited resource and its intended goal is to reduce anti‐D HDFN, more effective management of RhIG utilization is needed.

ABSTRACTImmune thrombotic thrombocytopenic purpura (iTTP) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and microvascular occlusion secondary to acquired ADAMTS13 deficiency. Contemporary data regarding iTTP treatment practices in the US, including the use of caplacizumab, are lacking. We aimed to characterize the demographics and therapies, including medications and apheresis practices, in patients with iTTP in the US. We retrospectively analyzed iTTP cases at 15 sites in the US that provide comprehensive care for patients with iTTP. The time‐period assessed was from January 1, 2017 to December 31, 2021. Our primary objective was to analyze data by iTTP episode, inclusive of initial episodes and relapses. A total of 390 iTTP episodes were reported for 280 unique individuals (187 females, 93 males). Thirty‐day mortality was 3.7% (14/374), and 6‐month mortality was 7.4% (27/367). TPE details were reported for 343 episodes, among which 261 underwent at least one procedure (median 6, IQR 3–11). Among the 261 episodes with at least one therapeutic plasma exchange (TPE) performed, 82.0% (214/261) used only plasma. Caplacizumab was used either alone or in combination with other agents in 43 (11.0%) episodes. Management strategies for iTTP remain varied across centers in the US, with a variety of combinations for TPE replacement fluids and therapeutic agents, as well as limited use of caplacizumab. Further research and standardization of treatment regimens may further reduce mortality in this condition.

ABSTRACTIn this first annual review article, the American Society for Apheresis (ASFA) Attending Physician Subcommittee (APSc) of the Physicians' Committee (PC) curated key apheresis literature in 2023 and presented their choices for the 10 most seminal apheresis articles. PubMed and OVID search engines were used to identify manuscripts from four topic areas: donor apheresis, therapeutic apheresis, education, and cellular therapy. To further identify seminal criteria, they had to present at least one of the following: novel findings, practice‐altering outcomes, international scope, randomized controlled trial, relevant to current clinical practice, and/or provide evidence for category III or IV indications based on the ASFA ninth special issue of the Guidelines on the Use of Therapeutic Apheresis in Clinical Practice‐Evidence‐Based Approach. Inclusion criteria included: full‐length, peer‐reviewed, English language, and human subjects. Case reports, review articles, and meta‐analyses were excluded.

AbstractBackgroundHemolytic disease of the fetus and newborn (HDFN) is caused by maternal alloantibody‐mediated destruction of fetal/neonatal red blood cells (RBCs). While the pathophysiology has been well‐characterized, the clinical and laboratory monitoring practices are inconsistent.MethodsWe surveyed 103 US institutions to characterize laboratory testing practices for individuals with fetuses at risk of HDFN. Questions included antibody testing and titration methodologies, the use of critical titers, paternal and cell‐free fetal DNA testing, and result reporting and documentation practices.ResultsThe response rate was 44% (45/103). Most respondents (96%, 43/45) assess maternal antibody titers, primarily using conventional tube‐based methods only (79%, 34/43). Among respondents, 51% (23/45) rescreen all individuals for antibodies in the third trimester, and 60% (27/45) perform paternal RBC antigen testing. A minority (27%, 12/45) utilize cell‐free fetal DNA (cffDNA) testing to predict fetal antigen status. Maternal antibody titers are performed even when the fetus is not considered to be at risk of HDFN based on cffDNA or paternal RBC antigen testing at 23% (10/43) of sites that assess titers.DiscussionThere is heterogeneity across US institutions regarding the testing, monitoring, and reporting practices for pregnant individuals with fetuses at risk of HDFN, including the use of antibody titers in screening and monitoring programs, the use of paternal RBC antigen testing and cffDNA, and documentation of fetal antigen results. Standardization of laboratory testing protocols and closer collaboration between the blood bank and transfusion medicine service and the obstetric/maternal‐fetal medicine service are needed.

AbstractPrior studies have suggested that immune thrombotic thrombocytopenic purpura (iTTP) may display seasonal variation; however, methodologic limitations and sample sizes have diminished the ability to perform a rigorous assessment. This 5‐year retrospective study assessed the epidemiology of iTTP and determined whether it displays a seasonal pattern. Patients with both initial and relapsed iTTP (defined as a disintegrin and metalloprotease with thrombospondin type motifs 13 activity <10%) from 24 tertiary centers in Australia, Canada, France, Greece, Italy, Spain, and the US were included. Seasons were defined as: Northern Hemisphere—winter (December–February); spring (March–May); summer (June–August); autumn (September–November) and Southern Hemisphere—winter (June–August); spring (September–November); summer (December–February); autumn (March–May). Additional outcomes included the mean temperature in months with and without an iTTP episode at each site. A total of 583 patients experienced 719 iTTP episodes. The observed proportion of iTTP episodes during the winter was significantly greater than expected if equally distributed across seasons (28.5%, 205/719, 25.3%–31.9%; p = .03). Distance from the equator and mean temperature deviation both positively correlated with the proportion of iTTP episodes during winter. Acute iTTP episodes were associated with the winter season and colder temperatures, with a second peak during summer. Occurrence during winter was most pronounced at sites further from the equator and/or with greater annual temperature deviations. Understanding the etiologies underlying seasonal patterns of disease may assist in discovery and development of future preventative therapies and inform models for resource utilization.

AbstractIntroductionApheresis practices in the United States (US) have not been comprehensively characterized to date. This study aimed to address this gap by evaluating apheresis therapy through a national survey.MethodsA multi‐institutional survey was conducted between April and July 2023. The survey, comprising 54 questions, focused on institutional demographics, procedures, equipment, staffing, training, and impacts of the Coronavirus Disease 2019 (COVID‐19) pandemic. Responses from 22 institutions, primarily academic medical centers, were analyzed.ResultsTherapeutic plasma exchange (TPE) was the most common procedure, followed by hematopoietic progenitor cell collection (HPC‐A) and red blood cell exchange (RCE). CAR‐T cell collections were widespread, with some institutions supporting over 30 protocols concurrently. Most sites used the Spectra Optia Apheresis System, were managed by a transfusion medicine service, and employed internal apheresis providers. Insufficient staffing levels, exacerbated by the COVID‐19 pandemic, were common and most often addressed using overtime.DiscussionThe survey highlighted the ubiquity of TPE, expanding cellular collections and staffing challenges. The role of apheresis in supporting cellular therapy, particularly in newly developing cell and gene therapies and clinical trials, was evident. Staffing issues during the pandemic emphasized the need for innovative recruitment strategies.ConclusionThis nationwide survey provides the most comprehensive analysis to date of apheresis practices in large US academic centers.