Stored platelet hemostatic phenotype and function is not altered when donors are on testosterone replacement therapy.

BACKGROUND: Critical shortages in the national blood supply have led to a re-evaluation of previously overlooked donor sources for blood products. As a part of that effort, red blood cells collected from therapeutic phlebotomy of donors on testosterone replacement therapy (TRT) have been conditionally approved for transfusion. However, platelets from TRT donors are not currently approved for use due to limited data on effects of supraphysiologic testosterone on recipient safety and platelet function. The objective of this study was to provide a comprehensive profile of phenotype and function in platelets from TRT and control donors. STUDY DESIGN AND METHODS: Platelets in plasma were collected from TRT and control donors (N = 10 per group; age- and sex-matched) and stored at room temperature for 7 days. On storage Day 1 (D1) and Day 7 (D7), platelet products were analyzed for platelet count, metabolic parameters (i.e., glucose, lactate, mitochondrial function), surface receptor expression, aggregation, thrombin generation, and thrombus formation under physiological flow conditions. RESULTS: TRT donor platelets were not significantly different than control donor platelets in terms of count, surface phenotype, metabolic function, ability to aggregate, thrombin generation, or ability to form occlusive thrombus under arterial flow regimes. Both groups were similar to each other by D7, but had significantly lost hemostatic function compared to D1. DISCUSSION: Platelets derived from donors undergoing TRT have similar phenotypic and functional profiles compared to those derived from control donors. This suggests that therapeutic phlebotomy of TRT donors may provide a useful source for platelet products.

Effective peripheral blood stem cell collection in a 4.6-kg child.

BACKGROUND: Due to unique technical challenges, effective peripheral blood stem cell collections (PBSCs) have not been consistently reported in patients weighing less than 5 kg. We describe three PBSCs performed in a 4.6-kg child undergoing myeloablative chemotherapy for high-grade glioma. STUDY DESIGN AND METHODS: A multidisciplinary group representing the clinical and apheresis teams adapted a PBSC protocol to accommodate the patient's size and collection targets. Special considerations included timing of the collection relative to chemotherapy, vascular access, strategies for monitoring adverse events during collection, and contingencies. RESULTS AND DISCUSSION: The patient underwent three PBSC procedures over 2 days due to suboptimal collection after the first two procedures. For procedure 1, a conservative inlet: anticoagulant (AC) ratio and AC infusion rate of 15 and 0.6 mL/min/L total blood volume (TBV) resulted in premature discontinuation due to clotting. A ratio of 8 and AC infusion rate of 1.5-1.7 mL/min/L TBV with subsequent titration to higher levels were adopted for the second and third procedures. These changes resulted in greater acid-citrate-dextrose exposure, that was managed by continuous calcium chloride infusion. There was no hypocalcemia, hypotension, or distress during any procedure. A total of 15 × 106 CD34+ cells/kg were collected. This retrospective review illustrates that PBSC can be safely undertaken in children weighing less than 5 kg.

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.

The Italian registry of therapeutic apheresis in SISTRA: Year of activity 2022.

Therapeutic apheresis refers to a group of extracorporeal blood processing procedures used in the treatment of a variety of systemic diseases. These complex procedures are burdened by adverse reactions related to both procedures and underlying medical conditions. Given the importance of centralizing the collection and the analysis of information on therapeutic apheresis, the Italian National Blood Center (NBC), at the request of the Italian Scientific Society of Hemapheresis and Cell Manipulation (SIdEM), implemented the Italian Registry of Therapeutic Apheresis (IRTA) including it in the Information System of Transfusion Services (SISTRA), coordinated by the NBC. In 2022, a total of 34,702 therapeutic apheresis procedures was carried out in 8,781 patients, including paediatric patients, with an average of 3.9 procedures per patient. The 2022 IRTA data indicate that the patient with hematological and/or neurological disorders mainly turns to the apheresis centers. These results confirm the IRTA data from years 2020 and 2021. In the hematological field, the apheresis centers supply hematopoietic stem cells collection for autologous transplantation as well as mononuclear cell collection for extracorporeal photopheresis. With regard to the neurological field, myasthenia, chronic inflammatory demyelinating polyneuropathy and Guillain-Barré syndrome along with other neurological pathologies related to immune disorders are the most treated. In conclusion, this manuscript presents 2022 activity data of IRTA providing institutions and scientific societies with a wide range of information including type and number of therapeutic procedures, adverse events and patients' outcome.

Treatment with plasma exchange of a pregnant woman with anti-PP1Pk alloimmunization: A case report.

The histo-blood group antigens P, P1 and Pk are a closely related set of glycosphingolipid structures expressed by red blood cells and other tissues. None of these three characters is expressed on p cells, a null phenotype that arises in the context of homozygous mutation of the A4GALT gene. Subjects with p phenotype spontaneously develop a natural alloantibody named anti-PP1Pk, which is a mixture of IgG and IgM against P1, P and Pk. While anti-P1 is a weak cold antibody with poor clinical significance, anti-P and anti-Pk antibodies are potent haemolysins responsible for severe hemolytic transfusion reactions. The rare anti-PP1Pk alloantibodies are associated with recurrent spontaneous abortion in the first trimester of gestation. P and Pk antigens are expressed at high levels on the placenta and antibodies directed against both these structures are deleterious to placental trophoblasts. Here we describe the use of plasma exchange (PEX) in a nulliparous 39-year-old woman with anti-PP1Pk antibodies and a history of repeated spontaneous early abortions and hypofertility. The patient underwent apheresis starting from the third week throughout the pregnancy and a healthy child was delivered by cesarean section at 35 WG. The newborn required only phototherapy within a few days of life. We can state that an early treatment with the only PEX has proven to be effective and safe in the management of a fetomaternal P-incompatibility caused by a high anti-PP1Pk titer (256).

Interest of therapeutic plasmapheresis in a chronic hemodialysis patient with severe bullous pemphigoid.

Bullous pemphigoid is the most common autoimmune blistering disease induced by autoantibodies against basement membrane anchoring proteins (anti-BP-180 and anti-BP-230). The disease generally appears after the age of 70 and is associated with a 23.5% 1-year mortality, especially in diabetics, or in the presence of ischemic heart disease and high anti-BP-180. Treatment starts with topical steroids but some patients may require oral steroids and systemic immunosuppression. We, hereby, discuss a diabetic patient on chronic hemodialysis, with severely relapsed bullous pemphigoid under biotherapy with omalizumab, who was successfully treated with five sessions of double filtration plasmapheresis, thus avoiding the need for systemic steroids.

Apheresis practice variation during the COVID-19 pandemic: Results of a survey.

BACKGROUND: The COVID-19 pandemic affected healthcare delivery across all specialties including apheresis. To describe the changes in apheresis service practices that occurred during the pandemic, the American Society for Apheresis (ASFA) Apheresis Medicine Attending Physician Subcommittee conducted a survey study. STUDY DESIGN AND METHODS: A 32-question survey was designed and distributed to 400 ASFA physician members on September 7, 2022. Attending physicians responded to questions about whether and how apheresis service practices changed during the COVID-19 pandemic compared with the time period prior to the pandemic in terms of: (1) procedure types and volumes, (2) patient consultation workflow, and (3) the use of telemedicine. Descriptive analyses were reported as number and frequency of responses. RESULTS: The survey response rate was 13.8% (55/400). Of these respondents, 96.4% (53/55) were attending physicians. The majority of respondents (42/53, 79.2%) indicated that the types of procedures performed during COVID-19 compared to pre-pandemic did not change. Most frequently for apheresis procedure volume, respondents reported: no change in their monthly inpatient volume (21/47, 44.7%) and a decrease in their monthly outpatient volume (28/46, 60.9%). Prior to COVID-19, 75.0% (30/40) of respondents performed consultations at bedside for inpatients and 67.4% (29/43) performed consultations at bedside for outpatients. Bedside consultations decreased in both settings during the pandemic but were still most frequently performed by attending physicians. At the same time, the use of telemedicine increased for 15.4% of survey respondents during COVID-19. CONCLUSION: Some, but not all, respondents observed or made changes to their apheresis service during the COVID-19 pandemic. A subset of changes, such as increased utilization of telemedicine, may persist.

Therapeutic apheresis in kidney transplantation: Emerging trends.

INTRODUCTION: The use of therapeutic apheresis (TA) either as stand-alone or adjunctive treatment in kidney transplantation has increased over the years to become a leading indication. This study shows recent trends in indications for TA related to kidney transplantation, adverse events, and patient outcome in this cohort. METHODS: This is a retrospective cohort review of adults who received TA for kidney transplant-related indications from January 1, 2017, to December 31, 2022, at the University of Virginia Medical Centre, Charlottesville, VA, USA. Data extracted include basic demographics, indication for apheresis, number of procedures, procedure characteristics, procedure-related adverse events (complications), and serum ionized calcium and serum creatinine. Data were analyzed using statistical package for social sciences (SPSS 2022 IBM Inc). RESULTS: Data from a total of 131 patients who received 860 TA procedures were analyzed. Indications for TA were antibody-mediated rejection (65.5%), recurrent focal segmental glomerulosclerosis (15%), thrombotic microangiopathy (5%), desensitization for ABO incompatibility (4.5%) and for HLA-incompatibility (4.5%), and recurrent IgA nephropathy (1%). Some adverse events were encountered in 16.7% of the procedures and include hypocalcemia (7%), vascular access malfunction (0.7%), hypotension (1.2%), arrhythmia (0.6%), and depletion coagulopathy (0.6%). The overall case mortality rate was 8.4% over the 6-year period. There was one death recorded on machine during TA resulting in a procedure-mortality rate of 0.12%. CONCLUSION: Antibody-mediated rejection was the most common indication for TA related to kidney transplantation. Adverse events were minor and patient survival over the time was within usual limits.

Plasma exchange-A useful adjunct therapy to red cell exchange in patients with sickle cell disease and multiorgan dysfunction.

BACKGROUND: Urgent red cell exchange (RBCx) is indicated for many complications of sickle cell disease (SCD), including acute chest syndrome, stroke, and hepatic/splenic sequestration. Many who receive RBCx remain hospitalized and develop further complications, including multiple organ dysfunction syndrome (MODS), a leading cause of death in intensive care units. Therapeutic plasma exchange (TPE) has been advocated as an effective treatment of MODS, but its role in SCD compared with RBCx alone is not well studied. METHODS: We identified all ICU encounters from 2013 to 2019 involving RBCx procedures for MODS or SCD crisis that progressed to MODS, a total of 12 encounters. Data regarding hospital length of stay (LOS), survival, number of TPE procedures following RBCx, and procedure characteristics were collected. Surrogate laboratory markers of end-organ damage and disease severity scores were recorded at the time of admission, post-RBCx, post-TPE, and at discharge. RESULTS: Eight encounters involved RBCx followed by TPE (TPE group) while four involved RBCx alone (RBCx group). The TPE group had a higher SOFA score at ICU admission (9.5 vs. 7.0), greater predicted mortality, and a statistical trend toward higher disease severity scores following RBCx relative to the RBCx group (p = 0.10). The TPE group showed a significantly greater decrease in SOFA score between RBCx and discharge (p = 0.04). No significant difference in mortality or hospital LOS was observed between the groups. CONCLUSION: The findings suggest TPE may be considered as an adjunct treatment for patients with acute complications of SCD that progress to MODS, especially in cases where there is no significant improvement following RBCx.

Durable remission of thrombotic thrombocytopenic purpura in the setting of pembrolizumab therapy.

BACKGROUND: There is a small but growing number of thrombotic thrombocytopenic purpura (TTP) cases attributed to immune checkpoint inhibitor therapy, with nivolumab and ipilimumab therapy being the most frequently described in the literature. STUDY DESIGN AND METHODS: This report evaluates the course of a patient with a history of metastatic adenocarcinoma of the lung who developed TTP following treatment with the PD-1 inhibitor Pembrolizumab. The patient was treated with six sessions of therapeutic plasma exchange and appeared to be in remission. Exacerbation occurred 4 days later, and seven more sessions of plasma exchange were performed along with four total doses of Rituximab, and a steroid taper with monitoring of platelet counts and ADAMTS13 activity. RESULTS: His platelet count recovered to a peak of 318,000 UL with an ADAMTS13 activity of 77% at the time of discharge. The patient has been following up regularly for outpatient testing with no TTP relapse as of the completion of this report. DISCUSSION: This is one of a few cases of Pembrolizumab-associated TTP reported in the literature with successful complete remission following treatment. Plasma exchange in this setting may be an especially beneficial therapeutic intervention because of the removal of both the anti-ADAMTS13 antibody as well as the immune system upregulating anti-PDL1 monoclonal antibody with replacement of ADAMTS13 from donor plasma. Longer duration of plasma exchange and monitoring for normalization of ADAMTS13 levels in addition to platelet count before cessation of treatment may improve durable remission rates in this entity.

Complications of red cell exchange for anemia management in patients with transfusion-dependent thalassemia.

BACKGROUND: In the Rare Blood Disorders clinic at the University of Alberta in Edmonton, red cell exchange (RCE) was utilized in transfusion-dependent thalassemia (TDT) patients with severe iron overload despite oral chelation and no access to iron infusion pumps for parenteral chelation. It was hypothesized that RCE would be less iron loading compared to simple transfusion. The purpose of this study is to document observations of the potential risks and benefits of RCE in TDT patients. STUDY DESIGN AND METHODS: TDT patients treated with RCE were identified and consented for enrolment according to local research ethics standards. Seven patients were enrolled in the study. Charts were retrospectively reviewed from the time of initiation of RCE to the time of the most recent RCE or clinic follow-up. Outcomes were documented and analyzed by descriptive analysis. RESULTS: The average age was 30 years. 85.7% were male. 100% were on oral chelation therapy and had hyperferritinemia at baseline. Outcomes included hepatic iron overload (5 of 7), cardiac dysfunction (3 of 7), worsening splenomegaly or extramedullary hematopoiesis (5 of 7), syncopal events during RCE (2 of 7), and new antibodies (1 of 7). Iron overload improved after escalated oral chelation, not in relation to RCE initiation. DISCUSSION: We hypothesize complications were higher than expected due to inadequate hematocrit increment and lack of suppression of ineffective erythropoiesis. With no observed benefit in iron status, and high complication rates, we did not find evidence to recommend RCE in patients with TDT. This case series is a hypothesis-generating study on transfusion techniques in TDT.

Hyperbaric treatment of platelets is comparable to cold storage alone over 14 days.

BACKGROUND: Platelets stored at room temperature (22-24°C) for transfusion purposes have a shelf life of 5-7 days, or 72 h when stored refrigerated (1-6°C). The limited shelf life of platelet products severely compromises platelet inventory. We hypothesized that cold storage of platelets in 100% plasma using xenon gas under high pressure would extend shelf life to 14 days. STUDY DESIGN AND METHODS: Double apheresis platelet units were collected and split equally between two bags. One unit was placed in a hyperbaric chamber, pressurized to 4 bars with a xenon/oxygen gas mixture, and placed in a refrigerator for 14 days (Xe). The remaining unit was aliquoted into mini-bags (10 ml) for storage at room temperature (RTP) or in cold (CSP). Samples were assayed on days 5 (RTP) or 14 (Xe and CSP) for count, metabolism, clot strength, platelet aggregation, and activation markers. RESULTS: The platelet count in Xe samples was lower than that of RTP but significantly higher than CSP. Despite similar levels of glucose and lactate, the pH of Xe samples was significantly lower than CSP. Glycoprotein expression was better preserved by Xe storage compared to CSP, but no differences in activation were observed. Thromboelastography and aggregometry results were comparable between all groups. DISCUSSION: Cold storage of platelets in plasma with hyperbaric xenon provides no significant improvement in platelet function over cold storage alone. The use of a hyperbaric chamber and the slow off-gassing of Xe-stored units complicate platelet storage and delivery logistics.

How do I initiate and maintain a mobile apheresis service in the era of cellular therapy.

BACKGROUND: Mobile delivery of apheresis services is an increasingly important component of health care equity, as patients should not have to transfer care providers or travel far distances to receive critical therapeutic apheresis procedures or cell therapy-based treatments. Therefore, the availability of such services should be expanded. STUDY DESIGN AND METHODS: In this "How Do I" article, we provide a detailed overview of the elements necessary to initiate and maintain a successful mobile apheresis service, including challenges and potential solutions. RESULTS: Safe and efficient operation of a mobile apheresis service must consider acquisition of physical assets, such as apheresis sites, personnel, equipment and supplies, communication devices, and transportation vehicles, and optimize organizational aspects, such as staff responsibilities, service partnerships, logistics management, case scheduling and triage, and billing. In the era of cellular therapy, additional critical considerations include regulatory compliance and facility accreditation. DISCUSSION: To our knowledge, no previous publication provides the extensive details described herein to set up and maintain a successful mobile apheresis service, and thus will be very helpful to those facilities wishing to initiate or expand mobile apheresis services.

Evaluating the efficiency and safety of large-volume leukapheresis using the Spectra Optia continuous mononuclear cell collection protocol for peripheral blood stem cell collection from healthy donors: A retrospective study.

BACKGROUND: Large-volume leukapheresis (LVL) refers to processing of more than three volumes of blood in a single session for peripheral blood stem cell collection. Recently, continuous mononuclear cell collection (cMNC) protocol has been developed using the Spectra Optia system, which is a widely used apheresis device. LVL using the novel protocol has been investigated in patients. However, the efficiency and safety of LVL in healthy donors using this protocol has not been characterized. Therefore, this study aimed to evaluate the efficiency and tolerability of CD34+ collection of LVL with the cMNC protocol in healthy donors. STUDY DESIGN AND METHODS: We retrospectively collected data on LVL (>3 total blood volume) and normal-volume leukapheresis (NVL) performed in healthy donors between October 2019 and December 2021. All procedures were performed using the cMNC protocol. RESULTS: Although pre-apheresis CD34+ cell count was lesser in LVL (23.5 vs. 58.0/µL, p < .001), CD34+ collection efficiency was comparable between LVL and NVL (61.2% vs. 61.4%, p = .966). Platelet loss was significantly higher in LVL compared to NVL (38.0% vs. 29.4%, p < .001), with no correlation between attrition of platelet and processing blood volume. Moreover, the incidence of citrate toxicity during procedures was comparable between the two groups (31.6% vs. 21.4%, p = .322). All LVL procedures could be completed without any adverse events. CONCLUSION: Allogeneic LVL procedure using Spectra Optia cMNC protocol was well tolerated by the donors and resulted in efficient collection of CD34+ cells, which was comparable to that of NVL.

Efficient granulocyte collection method using high concentrations of medium molecular weight hydroxyethyl starch.

BACKGROUND: Granulocyte transfusion therapy is a rational therapeutic option for patients with prolonged, severe neutropenia. Although high molecular weight hydroxyethyl starch (hHES) facilitates the separation of red blood cells during granulocyte collection, renal dysfunction has been noted as a potential side effect. HES130/0.4 (Voluven®) is a medium molecular weight HES (mHES) with superior safety profiles compared to hHES. Although HES130/0.4 is reportedly effective in the collection of granulocytes, we lack studies comparing the efficiency of granulocyte collection using HES130/0.4 and hHES. STUDY DESIGN AND METHODS: We retrospectively collected the data from 60 consecutive apheresis procedures performed on 40 healthy donors at the Okayama University Hospital between July 2013 and December 2021. All procedures were performed using the Spectra Optia system. Based on the HES130/0.4 concentration in the separation chamber, granulocyte collection methods using HES130/0.4 were classified into m0.46, m0.44, m0.37, and m0.8 groups. We used HES130/0.4 and hHES groups to compare the various sample collection methods. RESULTS: The median granulocyte collection efficiency (CE) was approximately 24.0% and 28.1% in the m0.8 and hHES groups, respectively, which were significantly higher than those in the m0.46, m0.44, and m0.37 groups. One month following granulocyte collection with HES130/0.4, no significant changes were observed in serum creatinine levels compared to those before the donation. CONCLUSION: Therefore, we propose a granulocyte collection approach employing HES130/0.4, which is comparable to the use of hHES in terms of the granulocyte CE. A high concentration of HES130/0.4 in the separation chamber was considered crucial for granulocyte collection.

How do we operate a large monthly red blood cell exchange program.

BACKGROUND: Red blood cell (RBC) exchange for sickle cell disease presents unique difficulties due to RBC phenotyping, complex antibody work-ups, large number of RBC units required, and vascular access considerations, any of which can delay the procedure. Multidisciplinary coordination and systemic processes ensure that monthly appointments remain on schedule. STUDY DESIGN AND METHODS: A high-volume chronic RBC exchange program is described, highlighting the importance of multidisciplinary coordination and process improvement strategies involving initial referral, vascular access, order sets, and allocation of antigen-negative or phenotypically matched RBCs. RESULTS: Approximately 50 outpatient RBC exchanges are performed each month with an 82% kept-appointment rate. Specific factors for program success include open communication across services and improvements to referrals and standardized order sets. CONCLUSION: A combination of multidisciplinary coordination and process improvement can ensure the success of a high volume RBC exchange program. Frequent communication of upcoming appointments between the referring hematologists, the hemapheresis clinic, transfusion service, and interventional radiology is critical. Advance notice to the immunohematology reference lab of upcoming appointments is needed to allow enough time for allocating antigen-negative RBCs. Order sets can be leveraged to standardize and streamline RBC exchanges. Lastly, numerous mechanisms help patients compensate for the cognitive sequelae of stroke.

An update on lipid apheresis for familial hypercholesterolemia.

Familial hypercholesterolemia (FH) is an inherited metabolic defect leading to increased total cholesterol and low-density cholesterol (LDL) from birth onwards. Homozygous FH, presenting with clear clinical features, has a prevalence of ~ 1 per million. Prevalence of heterozygous FH is 1/500 European population. Atherosclerotic burden depends on the degree and duration of high LDL exposure. In severe cases, early detection is critical, and aggressive lipid-lowering therapies should begin in early childhood to reduce coronary heart disease risk. Pediatric therapeutic concepts correspond to adults and are orientated at LDL plasma concentration. Mean LDL plasma target value during treatment is < 135 mg/dL. Medication in childhood consists of ezetemibe, statins, resins, and PCSK-9 inhibitors, with consideration for age restrictions. Only a minority achieve the treatment target with drug therapy alone. Therapeutic apheresis for the treatment of hypercholesterolemia selectively removes lipoproteins from blood (lipid apheresis (LA)). LA has a long tradition in adult medicine and is also safely used in children by a variety of methods, if customized to special pediatric needs. LA reduces cholesterol levels independently of residual LDL-receptor function and not only achieves reduction or disappearance of xanthomas but also inhibits progression of or mitigates aortic valve stenosis and supravalvular aortic stenosis as well as coronary artery and other atherosclerotic lesions. Cardiovascular prognosis of patients with otherwise untreatable FH depends largely on timely use of LA. Taking into account LA as a lifelong treatment, starting early in childhood, it is important to accommodate therapy modalities, such as treatment frequency and point of time, into the life of the individual.

Survey on the usage of therapeutic erythrocytapheresis in transfusion services in Italy for the treatment of polycythemia vera, secondary erythrocytosis and hemochromatosis.

INTRODUCTION: Erythrocytapheresis, an apheresis treatment which selectively removes red blood cells, is an alternative to therapeutic phlebotomy, over which it has several advantages. Actually there is a high degree of variability in the use of this treatment. This prompted SIdEM (Italian Society of Hemapheresis and Cell Manipulation) to conduct a survey on the use of erythrocytapheresis in the Italian Transfusion Services. The purpose is to monitor this activity in the treatment of Polycythemia Vera (pv), secondary erythrocytosis and hemochromatosis. MATERIALS AND METHODS: A data collection file was sent to the SIdEM regional delegates who, in turn, involved the Transfusion Centers in the areas they cover. The data collected were processed on a Microsoft Excel spreadsheet. RESULTS: 75 centers from 14 Italian regions responded to the Survey: 36 centers (48 %) use erythrocytapheresis (35 centers perform therapeutic apheresis and 1 center only donor apheresis), 39 centers (52 %) do not (15 centers perform therapeutic apheresis, 18 centers only donor apheresis and 6 centers do not perform either therapeutic apheresis or donor apheresis). Although most centers have a substantially uniform attitude concerning the indications for which erythrocytapheresis is used, the survey shows that there are still differences more evident in the treatment of secondary erythrocytosis than in the treatment of pv or hemochromatosis. CONCLUSIONS: This survey has been useful to document the current Italian reality and to raise awareness about the need for improvement in optimizing and standardizing the use of a therapy with a great potential to exploit properly.

Basic principles of therapeutic plasma exchange.

Therapeutic plasma exchange is a method of treatment for clinical conditions that represent diverse fields of medicine. The rationale for this mode of therapy is based on sound mathematical modeling of the synthesis and removal of large molecules, usually proteins, from the circulation. The basic assumptions underlying therapeutic plasma exchange are that a clinical illness is caused by, or related to, a pathogenic substance in the plasma, and that removing that substance from the plasma will alleviate the patient's illness. This approach has proven applicable to a wide variety of clinical conditions. Therapeutic plasma exchange is largely a safe procedure in experienced hands. The principal adverse effect, the hypocalcemic reaction, is readily ameliorated or prevented.

The Italian registry of therapeutic apheresis: year of activity 2021.

In 2019, the Italian National Blood Center (NBC), at the request of the Italian Scientific Society of Haemapheresis and Cell Manipulation (SIdEM), included the Italian Registry of Therapeutic Apheresis (IRTA) in the Information System of Transfusion Services (SISTRA), whose activity is coordinated by the NBC. The IRTA provides institutions and scientific societies with a wide range of information including therapeutic procedures and outcomes of treated patients. The Italian National Health Service offers therapeutic apheresis for patients with various conditions, but it is mainly the patient with haematological and/or neurological disorders who turns to the apheresis centres as evidenced by the activity data of 2021. In the haematological field, the apheresis centres mainly supply haematopoietic stem cells for autologous or allogeneic transplantation as well as mononuclear cell collection for extracorporeal photopheresis (ECP), a therapeutic approach of II line in post-transplant Graft versus Host Disease. The activity of 2021 in the neurological field confirms the data of 2019, the pre-pandemic year, and indicates that myasthenia, chronic inflammatory demyelinating polyneuropathy and Guillain-Barré syndrome along with other neurological pathologies related to immune disorders are the diseases in which apheresis procedures are most used. In conclusion, the IRTA is a valuable tool for monitoring the activity of apheresis centres carried out at a national level and above all for providing an overall picture of how the use of this therapeutic tool evolves and changes over time.