Using the World Apheresis Association Registry Helps to Improve the Treatment Quality of Therapeutic Apheresis

Trends in category and grade for therapeutic plasma exchange in the latest guideline on therapeutic apheresis by the American Society for Apheresis: Hurdles in pursuing evidence-based medicine

BACKGROUND AND OBJECTIVES

The Writing Committee of American Society for Apheresis released the ninth edition of guidelines for therapeutic apheresis in 2023. Categories have been a part of the guidelines since the first edition, and the grading system was introduced in the fifth edition, with updates in every new edition. In this study, we investigated the category and grade change trends through the latest five editions, focusing on therapeutic plasma exchange, to suggest future directions as part of evidence-based medicine.

MATERIALS AND METHODS

Categories and grades for therapeutic plasma exchange (TPE) were collected and analysed from the fifth through ninth editions. We aligned classification changes to the ninth edition's clinical context and compared its categories and grades with those introduced in the guideline.

RESULTS

Among 166 total indications in the ninth edition, 118 included TPE procedure, either as a sole treatment or as one of the therapeutic apheresis techniques. The total number of indications changed, but Category III remained predominant throughout the editions. Similarly, Grade 2C consistently emerged as the most prevalent grade. Notably, 24 cases had grade changes. Of the 16 cases with evidence quality changes, the quality weakened in six and improved in 10. Evidence levels were not improved throughout the study period for 102 clinical conditions.

CONCLUSION

To address gaps in evidence quality, international collaboration is imperative to establish comprehensive large-scale studies or randomized controlled trials. This will refine the use of therapeutic apheresis, including TPE, to foster evidence-based advancements in clinical practice.

Therapeutic plasma exchange is feasible and tolerable in severely injured patients with trauma-induced coagulopathy

Objectives

Trauma-induced coagulopathy (TIC) occurs in a subset of severely injured trauma patients. Despite having achieved surgical hemostasis, these individuals can have persistent bleeding, clotting, or both in conjunction with deranged coagulation parameters and typically require transfusion support with plasma, platelets, and/or cryoprecipitate. Due to the multifactorial nature of TIC, targeted interventions usually do not have significant clinical benefits. Therapeutic plasma exchange (TPE) is a non-specific modality of removing and replacing a patient's plasma in a euvolemic manner that can temporarily normalize coagulation parameters and remove deleterious substances, and may be beneficial in such patients with TIC.

Methods

In a prospective case series, TPE was performed in severely injured trauma patients diagnosed with TIC and transfusion requirement. These individuals all underwent a series of at least 3 TPE procedures performed once daily with plasma as the exclusive replacement fluid. Demographic, injury, laboratory, TPE, and outcome data were collected and analyzed.

Results

In total, 7 patients received 23 TPE procedures. All patients had marked improvements in routine coagulation parameters, platelet counts, a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activities, inflammatory markers including interleukin-6 concentrations, and organ system injuries after completion of their TPE treatments. All-cause mortality rates at 1 day, 7 days, and 30 days were 0%, 0%, and 43%, respectively, and all patients for whom TPE was initiated within 24 hours after injury survived to the 30-day timepoint. Surgical, critical care, and apheresis nursing personnel who were surveyed were universally positive about the utilization of TPE in this patient population. These procedures were tolerated well with the most common adverse event being laboratory-diagnosed hypocalcemia.

Conclusion

TPE is feasible and tolerable in severely injured trauma patients with TIC. However, many questions remain regarding the application of TPE for these critically ill patients including identification of the optimal injured population, ideal time of treatment initiation, appropriate treatment intensity, and concurrent use of adjunctive treatments.

Level of evidence

Level V.

The world apheresis association registry, 2023 update

The WAA apheresis registry contains data on more than 140,000 apheresis procedures conducted in 12 different countries. The aim is to give an update of indications, type and number of procedures and adverse events (AEs). MATERIAL AND METHODS: The WAA-registry is used for registration of apheresis procedures and is free of charge. The responsible person for a center can apply at the site www.waa-registry.org RESULTS: Data includes reported AEs from 2012 and various procedures and diagnoses during the years 2018-2022; the latter in total from 27 centers registered a total of 9500 patients (41% women) that began therapeutic apheresis (TA) during the period. A total of 58,355 apheresis procedures were performed. The mean age was 50 years (range 0-94). The most common apheresis procedure was stem cell collection for which multiple myeloma was the most frequent diagnosis (51%). Donor cell collection was done in 14% and plasma exchange (PEX) in 28% of patients; In relation to all performed procedures PEX, using a centrifuge (35%) and LDL-apheresis (20%) were the most common. The main indication for PEX was TTP (17%). Peripheral veins were used in 56% as the vascular access. The preferred anticoagulant was ACD. AEs occurred in 2.7% of all procedures and were mostly mild (1%) and moderate 1.5% (needed supportive medication) and, only rarely, severe (0.15%). CONCLUSION: The data showed a wide range of indications and variability in apheresis procedures with low AE frequency.

Plasma Exchange for Severe Immune-Related Adverse Events from Checkpoint Inhibitors: An Early Window of Opportunity?

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several advanced malignancies leading to durable remission in a subset of patients. Their rapidly expanding use has led to an increased frequency of immune-related adverse events (irAEs). The pathogenesis of irAEs is poorly understood but may involve aberrant activation of T cells leading to inflammatory cytokine release or production of pathogenic antibodies leading to organ damage. Severe irAEs can be extremely debilitating and, in some cases, life threatening. IrAEs may not always be corticosteroid responsive or may require excessively high, often toxic, corticosteroid doses. Therapeutic plasma exchange (PLEX) is a treatment modality that has shown promising results for the management of certain severe irAEs, including irAEs that are not mentioned in current treatment guidelines. PLEX may attenuate ongoing irAEs and prevent delayed irAEs by accelerating clearance of the ICI, or by acutely removing pathogenic antibodies, cytokines, and chemokines. Here, we summarize examples from the literature in which PLEX was successfully used for the treatment of irAEs. We posit that timing may be a critical factor and that earlier utilization of PLEX for life-threatening irAEs may result in more favorable outcomes. In individuals at high risk for irAEs, the availability of PLEX as a potential therapeutic mitigation strategy may encourage life-saving ICI use or rechallenge. Future research will be critical to better define which indications are most amenable to PLEX, particularly to establish the optimal place in the sequence of irAE therapies and to assess the ramifications of ICI removal on cancer outcomes.

Taking therapeutic apheresis services to patients in South Africa: An eight year review of SANBS mobile therapeutic apheresis service, 2013-2020

INTRODUCTION

A 20 year review of health and health care presents the multiple challenges faced by South Africans. Health and poverty is highlighted with 45% of population living on approximately US$ 2 per day and 10 million living on less than US$ 1 per day. Widening disparities in health care provision between public and private sector hospital services exist. The South African population includes the largest number of people living with HIV infection/AIDS of any country in the world, with a 70% estimate of 7.5 million people living with HIV on antiretroviral therapy. The South African National Blood Service provides a mixed model therapeutic apheresis service including mobile service and fixed-site therapeutic apheresis and an apheresis collection of hematopoietic stem cell (HPC-A) service. Therapeutic apheresis modalities offered by SANBS include plasmapheresis, red cell exchange, leukocyte and platelet reduction. In addition, collection of plasma, thrombocytes, mononuclear cells including CD34+ cells (HPCs) and granulocytes by apheresis for plasma and cellular therapies, and customised apheresis products for research purposes is offered. An operational database for the period 2013 to 2020 was reviewed to characterise the SANBS's mixed therapeutic apheresis service and HPC-A service from 2013 to 2020 in terms of patient numbers, patient demographics, patient procedures, therapeutic apheresis indication or diagnosis, therapeutic apheresis modality, hospital service type, and the American Society for Apheresis (ASFA) category of diagnosis.

METHODS

A retrospective review of therapeutic apheresis patients referred to SANBS characterising patient numbers, patient demographics, patient procedures, therapeutic apheresis indication or diagnosis, therapeutic apheresis modality (Linz, 2017), hospital service type, and the ASFA category of diagnosis (Padmanabhan et al., 2019) for the period 01 January 2013 to 31 December 2020 was completed. Data is obtained from a SANBS operational routinely utilised to record patient procedure data. Patient procedure data is manually recorded by apheresis nurses and indexed on to the operational database, with both processes audited. The review period is a convenience sample. Storage of the database and access of the operational database is in compliance with the Protection of Personal Information Act (Government Gazette, 2013). Therapeutic apheresis modalities analysed include Plasmapheresis, Red Cell Exchange, Leukopheresis, Thrombocytapheresis, Lymphocyte collection, Granulocyte collection, Haematopoietic stem cell collection by apheresis and customised apheresis products for research purposes. Customised apheresis products for research purposes is excluded from this review. Descriptive statistics is used.

RESULTS

For the review period, 2,485 unique patients with 120 unique indications as recorded by referring clinicians received 13,518 procedures involving 7 therapeutic apheresis modalities at 78 hospitals (21 public sector and 57 private sector) and at 3 SANBS blood donor centres in 7 provinces of South Africa. The age range of patients serviced is 4 months to 90 years (median = 39.5 years) (figure 1), 91% by procedure count was for patients 21 years of age or older, 62% were female, with 10,783 (79.6%) procedures performed in public sector hospitals. In all patients, the most common indications was plasmapheresis for thrombotic thromobocytopaenic purpura (52.5% of cumulative procedures), HPC-A for multiple myeloma (7.86%) and Antibody-mediated kidney transplant rejection (4.90%). Plasmapheresis was the most common therapeutic apheresis modality used (82.5% of cumulative procedures) followed by HPC-A (13.7%) and leukoreduction (3.39%). A range of indications for plasmapheresis (n = 65) and HPC-A (n = 41) were observed. Red cell exchange procedures was performed for patients with severe malaria and sickle cell disease indications. For leukoreduction indications, all patients were adults managed in public sector facilities and all were symptomatic. The most common indications were Chronic Myelogenous Leukemia, Chronic Lymphocytic Leukaemia and Multiple Myeloma. A pooled, total white cell count average of 457 × 10⁹/L (range 141-689 × 10⁹/L) prior to first procedure. Despite complex challenges for a national mixed model service, successful patient outcomes in emergent indications such as TTP (Louw et al., 2018; Swart et al., 2019) and engraftment post HPC-A in HSCT in multiple centres (Glatt, personal communication) are reported.

CONCLUSION

The review confirms that apheresis medicine is increasingly used in South Africa in patients in both public and private sector, with the most common modalities being plasmapheresis, HPC-A and leukoreduction. Patients with HIV-associated TTP is the most commonly referred patient in both paediatric and adult patients and this is anticipated to continue. A growing HSCT transplant network capacity in South Africa is augmented through the mixed model mobile and fixed-site therapeutic apheresis services, including a mobile HPC-A service. The increasing number of HPC-A is a trend towards increasing numbers of patients support to HSCT for both adults and paediatric patients in private and public sector hospitals.