Therapeutic apheresis: a review of complications and recommendations for prevention and management

Therapeutic apheresis treatment in rheumatic diseases: Insights from a single-center experience

INTRODUCTION

We aimed to evaluate the characteristics of the patients with a rheumatologic disease who underwent TPE.

METHOD

A single-center, retrospective study was conducted between January 2016 and June 2023.

RESULTS

Twenty patients with a median age of 51 years received a median of 6 TPE sessions. Concurrently, immunosuppressive therapy was administered to 18 (90%) of them. During the follow-up period, 9 patients (45%) died. Creatinine (p = 0.001), C-reactive protein (p = 0.001), sedimentation rate (p = 0.002), leukocyte (p = 0.003), thrombocyte (p = 0.003), and neutrophil (p = 0.003) counts was decreased after TPE. Similarly, in the ROC analysis of post TPE laboratory parameters, urea, creatinine, CRP, hemoglobin, platelets, and lymphocytes predicted mortality with areas under the curve values ranging from 0.747 to 0.869. In the Cox regression analysis for mortality, creatinine was predictive for mortality (p = 0.030), HR 1.59 (95% CI: 1.05-2.41).

CONCLUSION

In rheumatologic conditions, TPE is beneficial to fill the gap until the effects of immunosuppressants become apparent.

Selective red blood cell depletion by apheresis in sheep causes severe normovolemic anemia

BACKGROUND

The setting of normovolemic anemia is required for a variety of research applications, such as testing of novel medication for anemia treatment. Unfortunately, large animal models using full blood draw and replenishment with balanced electrolyte solution (BES) lead to bleeding complications, as coagulation factors and platelets are also drawn. We therefore aimed to establish a model of selective red blood cell (RBC) depletion to the main endpoint of hemoglobin (Hgb) levels of 4-6 g dL-1 using apheresis in sheep.

METHODS

In vitro experiments were performed first to establish the apheresis protocol. In vivo, anesthetized ewes underwent a sham protocol without apheresis (n = 5) or apheresis (n = 4). Both groups were observed for the following six hours at a defined starting point (BE0) to compare Hgb, hematocrit (Hct), coagulation and clinical parameters. For statistical analysis, unpaired t-test with Welch`s correction was used.

RESULTS

Hgb levels were effectively decreased by 51 % to mean Hgb of 4.4 g dL-1 in the apheresis group compared to 9.1 g dL-1 in sham (*p < 0.0001). Hct (11.2% vs 25.1 %, *p = 0.01) and RBCs (3.7 vs 8.2 × 106/µl, *p = 0.003) also decreased. The relative number of platelets compared to baseline was different (55.6 ± 10.6% vs. 100 ± 0 %, *p = 0.004), but no hemorrhage was observed. White blood cells (WBCs), lactate, prothrombin ratio and activated partial thromboplastin time (aPTT) remained within similar ranges.

CONCLUSIONS

Critical normovolemic anemia without bleeding complications was successfully reached by selective RBC depletion in sheep. Investigations of physiological adaptations to severe anemia and pharmaceutical testing can be performed in large animals with depleted RBCs.

Complications of therapeutic plasma exchange: A retrospective, single-center study of 2505 procedures performed in 338 patients over 15 years

INTRODUCTION

Therapeutic plasma exchange (TPE) may involve complications. We aimed to review the demographic data, indications, technical information, and complications.

METHODS

Data for TPE procedures (TPEPs) performed between 2004 and 2018 were retrospectively.

RESULTS

This study covered 2505 TPEPs performed on 338 patients; 55% of them were female (n = 186), and the median age was 36 years (range, 11-93 years). Most TPEPs were administered for hematological (40.6%) indications. The incidence of complications on the first procedure was 3.2% (n = 80); only 16 procedures (0.6%) were failed. The complication incidence was 19.8% (n = 497), with 789 total complications. Most of the complications were patient-related (90.4%), and the most of them were urticaria (29.1%), occlusion (3.2%), and faulty systems (1.01%), respectively. The use of only fresh frozen plasma as replacement fluid caused a higher complication rate (22.1%, p < 0.01).

CONCLUSION

The number of TPEPs is increasing every day. Hematologic indications for TPE and the use of fresh frozen plasma may increase the risk of complications.

Risk assessment for hypocalcemia in therapeutic apheresis for kidney transplantation

INTRODUCTION

The increase in the number of kidney transplants performed in the United States has been paralleled with an increase in the utilization of therapeutic apheresis (TA) for kidney transplant indications. Hypocalcemia remains a significant contributor to the adverse event in TA. The magnitude of hypocalcemia and its risk factors are scarcely discussed in literature.

METHODS

This is a retrospective cohort review of adults from 18 years and above who received TA for kidney transplant-related indications from January 1, 2017 to December 31, 2022. Data extracted included basic demographics, indication for apheresis, procedure characteristics, serum ionized calcium at the mid and end of procedure and serum creatinine at the beginning of apheresis, and so forth.

RESULTS

Data from 131 patients and 860 sessions of TA were analyzed. Antibody-mediated rejection (69%) and recurrent FSGS (15%) were the leading indications for TA. There were 60 (7%) TA sessions complicated by hypocalcemia. Of these, 53 (88%) occurred in the first session, 5 (8%) occurred in second session while 2 (4%) occurred in the third and subsequent sessions. Female sex, elevated serum creatinine and use of fresh frozen plasma- are the risk factors for hypocalcemia with odd's ratio of 2.34, 7.42, and 5.01, respectively. Binary logistic regression showed that elevated serum creatinine at the commencement of therapy is an independent predictor of hypocalcemia (adjusted odd's ratio = 3.31, p = 0.001).

CONCLUSION

Hypocalcemia is prevalent in this study. Clinical vigilance and tailored procedure will avert adverse consequences.

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.

Establishment of an adverse effect prevention protocol on plasma exchange using fresh frozen plasma prior to ABO-incompatible living donor kidney transplantation at our hospital

INTRODUCTION

Simple plasma exchange (PE) with fresh-frozen plasma replacement allows antibody removal for ABO-incompatible living donor kidney transplantation, but is associated with a high incidence of allergic reactions. We developed, implemented, and evaluated a protocol for safe preoperative PE.

METHODS

The protocol comprised pretreatment (125 mg methylprednisolone infusion, 400 mg acetaminophen and 30 mg diphenhydramine orally) with a replacement fluid rate < 20 mL/min. Allergic reaction incidence was investigated in controls who underwent ABO-incompatible living donor kidney transplantation between 2016 and March 2020 (group C) and patients who underwent the protocol and procedure between April 2020 and February 2023 (group N).

RESULTS

Ten (group C) and 19 (group N) patients performed 11 and 30 sessions of PE, respectively. Allergic reactions occurred in 81.8% and 36.7% (p = 0.014), respectively, with an odds ratio of the protocol was 0.056 (95% CI 0.0059-0.5380, P = 0.013).

CONCLUSION

Our protocol resulted in a significantly lower incidence of allergic reactions.

Red Blood Cell Exchange as a Valid Therapeutic Approach for Pregnancy Management in Sickle Cell Disease: Three Explicative Cases and Systematic Review of Literature

Pregnancy in women with sickle cell disease (SCD) is a high-risk situation, especially during the third trimester of gestation and in the post-partum period, due to chronic hypoxia and vaso-occlusive phenomena occurring in the maternal-fetal microcirculation: as a result, unfavorable outcomes, such as intra-uterine growth restriction, prematurity or fetal loss are more frequent in SCD pregnancies. Therefore, there is a consensus on the need for a strict and multidisciplinary follow-up within specialized structures. Transfusion support remains the mainstay of treatment of SCD pregnancies, whereas more targeted modalities are still controversial: the benefit of prophylactic management, either by simple transfusions or by automated red blood cell exchange (aRBCX), is not unanimously recognized. We illustrate the cases of three SCD pregnant patients who underwent aRBCX procedures at our institution in different clinical scenarios. Moreover, we carried out a careful literature revision to investigate the management of pregnancy in SCD, with a particular focus on the viability of aRBCX. Our experience and the current literature support the use of aRBCX in pregnancy as a feasible and safe procedure, provided that specialized equipment and an experienced apheresis team is available. However, further research in this high-risk population, with appropriately powered prospective trials, is desirable to refine the indications and timing of aRBCX and to confirm the advantages of this approach on other transfusion modalities.

Long noncoding RNA SNHG16 regulates TLR4-mediated autophagy and NETosis formation in alveolar hemorrhage associated with systemic lupus erythematosus

BACKGROUND

Dysregulated long noncoding RNA (lncRNA) expression with increased apoptosis has been demonstrated in systemic lupus erythematosus (SLE) patients with alveolar hemorrhage (AH). SNHG16, a lncRNA, can enhance pulmonary inflammation by sponging microRNAs, and upregulate toll-like receptor 4 (TLR4) expression via stabilizing its mRNAs. TRAF6, a TLR4 downstream signal transducer, can induce autophagy and NETosis formation. In this study, we investigated whether SNHG16 could regulate TLR4-mediated autophagy and NETosis formation in SLE-associated AH.

METHODS

Expression of SNHG16, TLR4 and TRAF6 and cell death processes were examined in lung tissues and peripheral blood (PB) leukocytes from AH patients associated with SLE and other autoimmune diseases, and in the lungs and spleen from a pristane-induced C57BL/6 mouse AH model. SNHG16-overexpressed or -silenced alveolar and myelocytic cells were stimulated with lipopolysaccharide (LPS), a TLR4 agonist, for analyzing autophagy and NETosis, respectively. Pristane-injected mice received the intra-pulmonary delivery of lentivirus (LV)-SNHG16 for overexpression and prophylactic/therapeutic infusion of short hairpin RNA (shRNA) targeting SNHG16 to evaluate the effects on AH. Renal SNHG16 expression was also examined in lupus nephritis (LN) patients and a pristane-induced BALB/c mouse LN model.

RESULTS

Up-regulated SNHG16, TLR4 and TRAF6 expression with increased autophagy and NETosis was demonstrated in the SLE-AH lungs. In such patients, up-regulated SNHG16, TLR4 and TRAF6 expression was found in PB mononuclear cells with increased autophagy and in PB neutrophils with increased NETosis. There were up-regulated TLR4 expression and increased LPS-induced autophagy and NETosis in SNHG16-overexpressed cells, while down-regulated TLR4 expression and decreased LPS-induced autophagy and NETosis in SNHG16-silenced cells. Pristane-injected lung tissues had up-regulated SNHG16, TLR4/TRAF6 levels and increased in situ autophagy and NETosis formation. Intra-pulmonary LV-SNHG16 delivery enhanced AH through up-regulating TLR4/TRAF6 expression with increased cell death processes, while intra-pulmonary prophylactic and early therapeutic sh-SNHG16 delivery suppressed AH by down-regulating TLR4/TRAF6 expression with reduced such processes. In addition, there was decreased renal SNHG16 expression in LN patients and mice.

CONCLUSIONS

Our results demonstrate that lncRNA SNHG16 regulates TLR4-mediated autophagy and NETosis formation in the human and mouse AH lungs, and provide a therapeutic potential of intra-pulmonary delivery of shRNA targeting SNHG16 in this SLE-related lethal manifestation.

Therapeutic plasma exchange in anti-N-methyl-D-aspartate receptor encephalitis

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most commonly identified cause of autoimmune encephalitis. Therapeutic plasma exchange has been increasingly employed to treat this disease. This expansion is a consequence of improved techniques and apheresis instruments, as well as the recognition of its applicability in neurological diseases. However, several aspects of treatment remain incompletely clarified, and treatment strategies are still heterogeneous, especially with regard to therapeutic plasma exchange in anti-NMDAR encephalitis. This review provides an overview of the use of therapeutic plasma exchange including the principle and mechanisms, the evidence, initial time, efficiency and complications in anti-NMDAR encephalitis.

Comparison of outcomes and costs of extracorporeal blood purification therapies in critically ill COVID-19 patients

INTRODUCTION

Plasmapheresis and hemoperfusion are used against cytokine release syndrome in COVID-19. This study aims to compare their outcomes, costs, and side-effects.

METHODS

Survival, costs and side-effects were compared in intensive care unit (ICU) patients receiving plasmapheresis (n = 49), hemoperfusion (n = 20), or none (n = 107), followed until death or discharge.

RESULTS

Plasmapheresis survival time was higher than hemoperfusion or controls (HR = 0.764, p = 0.397 and HR = 0.483, p = 0.002, respectively), although the latter diminished after controlling for age and disease severity (p = 0.979). There was no significant difference in ICU costs for plasmapheresis and hemoperfusion (p = 0.738) while both costed more than controls (both p < 0.001). Hypocalcemia and thrombocytopenia incidence did not differ between two groups (p = 0.124 and p = 0.389, respectively) while being higher than controls in plasmapheresis (both p < 0.001) and hemoperfusion (p < 0.001 and p = 0.056, respectively).

CONCLUSION

Plasmapheresis and hemoperfusion do not differ significantly in patient survival, ICU costs and side-effects with a higher incidence of hypocalcemia and thrombocytopenia compared witcontrols.

Autoantibodies as Biomarker and Therapeutic Target in Systemic Sclerosis

Systemic sclerosis (SSc) is a rare connective tissue disorder characterized by immune dysregulation evoking the pathophysiological triad of inflammation, fibrosis and vasculopathy. In SSc, several alterations in the B-cell compartment have been described, leading to polyclonal B-cell hyperreactivity, hypergammaglobulinemia and autoantibody production. Autoreactive B cells and autoantibodies promote and maintain pathologic mechanisms. In addition, autoantibodies in SSc are important biomarkers for predicting clinical phenotype and disease progression. Autoreactive B cells and autoantibodies represent potentially promising targets for therapeutic approaches including B-cell-targeting therapies, as well as strategies for unselective and selective removal of autoantibodies. In this review, we present mechanisms of the innate immune system leading to the generation of autoantibodies, alterations of the B-cell compartment in SSc, autoantibodies as biomarkers and autoantibody-mediated pathologies in SSc as well as potential therapeutic approaches to target these.

COVID-19 and Therapeutic Apheresis

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is an unprecedented challenge for the global community. The pathogenesis of COVID-19, its complications and long term sequelae (so called Long/Post-COVID) include, in addition to the direct virus-induced tissues injury, multiple secondary processes, such as autoimmune response, impairment of microcirculation, and hyperinflammation. Similar pathological processes, but in the settings of neurological, cardiovascular, rheumatological, nephrological, and dermatological diseases can be successfully treated by powerful methods of Therapeutic Apheresis (TA). We describe here the rationale and the initial attempts of TA treatment in severe cases of acute COVID-19. We next review the evidence for the role of autoimmunity, microcirculatory changes and inflammation in pathogenesis of Long/Post COVID and the rationale for targeting those pathogenic processes by different methods of TA. Finally, we discuss the impact of COVID-19 pandemic on patients, who undergo regular TA treatments due to their underlying chronic conditions, with the specific focus on the patients with inherited lipid diseases being treated at the Dresden University Apheresis Center.

Role of therapeutic apheresis in the treatment of pediatric kidney diseases

Therapeutic apheresis utilizes apheresis procedures in the treatment of a variety of conditions including kidney disease. Therapeutic plasma exchange (TPE) is the most common modality employed with the rationale of rapid reduction of a pathogenic substance distributed primarily in the intravascular compartment; however other techniques which adsorb such pathogenic substances or alter the immune profile have been utilized in diseases affecting native and transplanted kidneys. This article discusses the modalities and technical details of therapeutic apheresis and summarizes its role in individual diseases affecting the kidney. Complications related to pediatric apheresis procedures and specifically related to apheresis in kidney disease are also discussed. Though therapeutic apheresis modalities are employed frequently in children with kidney disease, most experiences are extrapolated from adult studies. International and national registries need to be established to elucidate the role of apheresis modalities in children with kidney disease.

Efficacy of peripheral arterial access for peripheral blood stem cells collection

BACKGROUND

Transplantation of peripheral blood stem cells (PBSCs) mobilized by cytokines is increasingly applied to treat patients with hematologic diseases, such as lymphoma, multiple myeloma, leukemia, etc. Successful hematopoietic stem cell transplantation (HSCT) increasingly depends on the collection of hematopoietic stem cells (HSCs) from peripheral blood. Peripheral vein (PV) is the most common type of blood access. When the blood vessels are not well filled and the blood flow is insufficient, the machine will appear repeated low pressure alarm or pipeline coagulation, which seriously affects the collection efficiency. A peripheral artery (PA) is utilized for drawing blood, while a peripheral vein is used for blood return, that is a way to perform apheresis. The advantages of PA are that it ensures adequate extracorporeal circulation blood flow, stable blood flow rate, simple operation, and relatively low price. However, there are very few studies on the efficacy of peripheral arterial access for HSCs collection. Therefore, this retrospective study was conducted to assess the effectiveness of PA and PV access for PBSCs collection.

METHODS

We performed a retrospective analysis of 150 apheresis procedures on 26 patients and 95 healthy donors collected by PV or PA access from March 1, 2020 to March 1, 2021. We compared the CD34+ cell count, collection efficiency (CE), duration of processing a single blood volume, number of low-pressure alarms, average blood flow rate and number of punctures between the two groups. Also, we analyzed adverse events.

RESULTS

There was no significant difference in the quality of apheresis blood components between the PA group and the PV group. The CD34+ cells collected was 274.16 ± 216.31 × 10⁶ in the PV group and 246.63 ± 127.94 × 10⁶ in the PA group. The CE in the PA group was 49.50 ± 9.88%, higher than 42.39 ± 14.62% in the PV group. The duration of processing a single blood volume was 90.67 ± 15.35 min in the PV group and 79.68 ± 10.28 min in the PA group. The number of low-pressure alarms in the PA group was 0.38 ± 0.98, <2.42 ± 1.76 in the PV group, and the average blood flow rate in the PA group was 59.27 ± 2.18, higher than 54.21 ± 3.41 in the PV group. The difference was statistically significant (P < .05). The Number of punctures was 1.35 ± 0.75 in the PA group and 1.41 ± 1.01 in the PV group. There was no statistically significant difference.

CONCLUSION

Peripheral artery is a safe, reliable, economical, convenient, and fast vascular access, which opens a new way to the establishment of vascular access for PBSCs collection.

Therapeutic plasma exchange in liver failure

The multi-organ failure syndrome associated with acute and acute-on-chronic liver failure (ACLF) is thought to be mediated by overwhelming systemic inflammation triggered by both microbial and non-microbial factors. Therapeutic plasma exchange (TPE) has been proven to be an efficacious therapy in autoimmune conditions and altered immunity, with more recent data supporting its use in the management of liver failure. Few therapies have been shown to improve survival in critically ill patients with liver failure who are not expected to survive until liver transplantation (LT), who are ineligible for LT or who have no access to LT. TPE has been shown to reduce the levels of inflammatory cytokines, modulate adaptive immunity with the potential to lessen the susceptibility to infections, and reduce the levels of albumin-bound and water-bound toxins in liver failure. In patients with acute liver failure, high volume TPE has been shown to reduce the vasopressor requirement and improve survival, particularly in patients not eligible for LT. Standard volume TPE has also been shown to reduce mortality in certain sub-populations of patients with ACLF. TPE may be most favorably employed as a bridge to LT in patients with ACLF. In this review, we discuss the efficacy and technical considerations of TPE in both acute and acute-on-chronic liver failure.

The Rise of SARS-CoV-2 Variants and the Role of Convalescent Plasma Therapy for Management of Infections

Novel therapies for the treatment of COVID-19 are continuing to emerge as the SARS-Cov-2 pandemic progresses. PCR remains the standard benchmark for initial diagnosis of COVID-19 infection, while advances in immunological profiling are guiding clinical treatment. The SARS-Cov-2 virus has undergone multiple mutations since its emergence in 2019, resulting in changes in virulence that have impacted on disease severity globally. The emergence of more virulent variants of SARS-Cov-2 remains challenging for effective disease control during this pandemic. Major variants identified to date include B.1.1.7, B.1.351; P.1; B.1.617.2; B.1.427; P.2; P.3; B.1.525; and C.37. Globally, large unvaccinated populations increase the risk of more and more variants arising. With successive waves of COVID-19 emerging, strategies that mitigate against community transmission need to be implemented, including increased vaccination coverage. For treatment, convalescent plasma therapy, successfully deployed during recent Ebola outbreaks and for H1N1 influenza, can increase survival rates and improve host responses to viral challenge. Convalescent plasma is rich with cytokines (IL-1β, IL-2, IL-6, IL-17, and IL-8), CCL2, and TNFα, neutralizing antibodies, and clotting factors essential for the management of SARS-CoV-2 infection. Clinical trials can inform and guide treatment policy, leading to mainstream adoption of convalescent therapy. This review examines the limited number of clinical trials published, to date that have deployed this therapy and explores clinical trials in progress for the treatment of COVID-19.

Targeting Intra-Pulmonary P53-Dependent Long Non-Coding RNA Expression as a Therapeutic Intervention for Systemic Lupus Erythematosus-Associated Diffuse Alveolar Hemorrhage

Diffuse alveolar hemorrhage (DAH) in systemic lupus erythematosus (SLE) is associated with significant mortality, requiring a thorough understanding of its complex mechanisms to develop novel therapeutics for disease control. Activated p53-dependent apoptosis with dysregulated long non-coding RNA (lncRNA) expression is involved in the SLE pathogenesis and correlated with clinical activity. We examined the expression of apoptosis-related p53-dependent lncRNA, including H19, HOTAIR and lincRNA-p21 in SLE-associated DAH patients. Increased lincRNA-p21 levels were detected in circulating mononuclear cells, mainly in CD4+ and CD14+ cells. Higher expression of p53, lincRNA-p21 and cell apoptosis was identified in lung tissues. Lentivirus-based short hairpin RNA (shRNA)-transduced stable transfectants were created for examining the targeting efficacy in lncRNA. Under pristane stimulation, alveolar epithelial cells had increased p53, lincRNA-p21 and downstream Bax levels with elevated apoptotic ratios. After pristane injection, C57/BL6 mice developed DAH with increased pulmonary expression of p53, lincRNA-p21 and cell apoptosis. Intra-pulmonary delivery of shRNA targeting lincRNA-p21 reduced hemorrhage frequencies and improved anemia status through decreasing Bax expression and cell apoptosis. Our findings demonstrate increased p53-dependent lncRNA expression with accelerated cell apoptosis in the lungs of SLE-associated DAH patients, and show the therapeutic potential of targeting intra-pulmonary lncRNA expression in a pristane-induced model of DAH.

Therapeutic plasma exchange in pregnancy: A literature review

Therapeutic plasma exchange (TPE) is indicated as a treatment for a wide array of diseases, extensively addressed in the Guidelines of the American Society for Apheresis. In pregnancy, TPE is an uncommon event and application is largely based on extrapolation of efficacy and safety in a non-pregnant population. This review intends to describe the currently available experience of TPE in pregnancy to help clinicians recognise indications during pregnancy and to support current guideline recommendations with literature-based experiences. In order to identify the clinical indications for which TPE is applied in pregnant women, we performed a literature search including studies till November 2019, without a start date restriction. Data extraction included medical indication for TPE and safety of TPE in pregnant women. 279 studies were included for analysis. Nowadays, TPE is predominantly applied for thrombotic microangiopathies, lipid disorders and a variety of autoimmune diseases. The application of TPE during pregnancy remains largely empiric and relies on individual case reports in the absence of high-quality studies and definitive evidence-based guidelines. Safety profile of TPE during pregnancy appears to be comparable to application of TPE in non-pregnant patients. In conclusion, based on the limited evidence that we found in literature with a high risk of publication bias, TPE procedures can be used safely during pregnancy with the appropriate preparation and experience of a multidisciplinary team.

Use of therapeutic plasma exchange in heparin-induced thrombocytopenia: A population-based study

BACKGROUND

Heparin-induced thrombocytopenia (HIT) is characterized by anti-heparin/platelet factor 4 immune complexes, which are removed by therapeutic plasma exchange (TPE). Our main objective was to study TPE outcomes in HIT using a large administrative claims database.

STUDY DESIGN AND METHODS

We used the National Inpatient Sample (NIS) to identify hospital discharges of adult patients (≥18) with a primary or secondary diagnosis of HIT. Cases were classified into two groups based on TPE use. The primary outcome was in-hospital mortality. Secondary outcomes were thrombotic events, major bleeding, hospital length of stay (LOS), and charges. Multivariable regression analysis, controlling for age and medical comorbidities, was used to examine the association of TPE with study outcomes.

RESULTS

A HIT diagnosis was made in 22 165 discharges, of which 90 (0.4%) received TPE. Corresponding national estimates are 106 435 and 439, respectively. TPE was not associated with decreased in-hospital mortality (OR = 1.72; 95%CI: 0.93-3.17, P = .085). However, TPE was associated with a higher likelihood of major bleeding (OR = 2.35; 95%CI: 1.40-3.68, P = .0009), primarily driven by gastrointestinal bleeding (OR = 2.21; 95%CI: 1.17-4.17, P = .015). TPE was also associated with higher hospital LOS (20.5 vs 10 day, P < .0001) and charges (USD 211181 vs USD 81654, P < .0001).

CONCLUSION

TPE's association with increased bleeding and a prolonged hospital course indicates that it is being used in HIT cases with a severe clinical phenotype. Future studies are needed to better characterize the HIT phenotype that will most benefit from TPE.

Therapeutic plasma exchange an emerging treatment modality: A 3-year retrospective analysis of patients admitted in a multispecialty hospital of North India

BACKGROUND AND AIMS

Therapeutic plasma exchange (TPE) is increasingly used throughout the medical field. We aimed to analyze the various aspects of TPE practices at our hospital in terms of clinical indications, technical feasibility, safety, outcome as well as complications associated with the procedures.

MATERIALS AND METHODS

The data included demographic profiles, clinical parameters, and technical characteristics of each TPE procedure. All the information was noted in data spread sheet (Microsoft Excel 2013) for further analysis.

RESULTS

This is a 3-year retrospective study of total 266 TPE procedures carried out on 92 patients with different clinical conditions. Out of them, 55 (59.8%) were male and 37 (40.2%) were female patients. There were six major categories such as (1) neurological, (2) hematological, (3) gastrological, (4) renal, (5) rheumatic, and (6) others. The TPE treatment was highest in neurology group (60.2%), followed by gastrology group (24.4%). Most of the procedures (82.6%) were according to the American society of apheresis 2016 I or II categories (76/92 patients).

CONCLUSION

TPE is beneficial and used as primary or secondary adjunctive therapy for a wide spectrum of various diseases and syndromes. TPE is considered as safe, cost-effective, and life-saving treatment modality in various diseases.

Therapeutic leukapheresis and thrombapheresis in medical emergencies

The management of hyperleukocytosis or thrombocytosis by therapeutic cytapheresis in the early 21 st century is far from codified (universal). Therapeutic cytapheresis have been proposed to achieve more rapid cytoreduction in peripheral blood than old universal support in order to quickly prevent potential complications. But, there are no randomized studies demonstrating the superiority of cytapheresis over other treatments alone. In this short review, based on our own experience (since 1980), we will give the indications and the role of cytapheresis procedures and we will try to answer the questions: when is therapeutic cytapheresis appropriate and do they still have a place in 2020, especially as a medical emergency?

Potential of therapeutic plasmapheresis in treatment of COVID-19 patients: Immunopathogenesis and coagulopathy

Therapeutic plasmapheresis (TP) is the process of the separation and removal of plasma from other blood components and is considered as an adjunctive treatment strategy to the discarded abnormal agent in the management of respiratory viral pandemics. This article reviews the mechanisms of immunopathogenesis and coagulopathy induced by SARS-CoV-2 and the potential benefits of TP as adjunctive treatment in critically COVID-19 patients.

Membrane-Based Therapeutic Plasma Exchange in Intensive Care

The principles and use of plasmapheresis are often little understood by intensivists. We propose to review the principles, the main indications, and the methods of using this technique.

Vascular access for optimal hematopoietic stem cell collection

BACKGROUND

Autologous and allogeneic hematopoietic stem cell transplantation of cytokine-mobilized peripheral blood stem cells (PBSCs) is increasingly used to treat patients with hematologic disorders. Different types of vascular access have been exploited for the apheresis procedure, including peripheral veins (PV) and central venous catheter (CVC). In some cases, PV access is unavailable. There are few published data on the efficiency and quality of harvesting with different types of vascular access. This study brings out complications and morbidity of this procedure linked to these different access.

METHODS

We performed a comparative, retrospective, single-center study of hematopoietic stem cell collection using these two types of vascular access. We compared the efficiency and complication rate for 617 adults apheresis sessions in 401 patients and healthy donors, for PBSC collection via PV or CVC between 2010 and 2016. The quality of the HSC product was evaluated in terms of the total CD34 + count and neutrophil contamination.

RESULTS

The PV and CVC groups did not differ significantly in terms of the quality of the apheresis product, mean ± SD CD34 + cells collected in PV group was 383.1 ± 402.7 × 10e6 and 298.8 ± 372.7 × 10e6 and the level of neutrophil contamination was 21.0 ± 17.8% in the PV group and 20.6 ± 18.4% in the CVC group. The complication rate did not differ between the two groups.

CONCLUSION

The type of vascular access for apheresis hematopoietic stem cell harvesting must be determined by trained staff. Successful harvesting can be performed via PV then CVC is not needed or not available.

Peripheral vascular access for therapeutic plasma exchange: A practical approach to increased utilization and selecting the most appropriate vascular access

BACKGROUND

Therapeutic plasma exchange (TPE) is used in the treatment of many diseases. At present, peripheral vascular access (PVA) is an underutilized method of vascular access in TPE. It should be considered more frequently due its relatively low risk for adverse events, particularly infections.

METHODS

The Advancing Vascular Access in Apheresis Working Group met in December 2017 for an extensive review and discussion of vascular access for TPE and developed a "road map" providing detailed information regarding clinical situations in which PVA-based TPE would and would not be appropriate.

RESULTS

The road map is consistent with current recommendations that PVA should be used in combination with TPE whenever possible. PVA should be considered for patients who do not have existing central lines and who are stable. The patient should have peripheral veins that will allow for adequate treatment and must be able to comply with the process of achieving and maintaining peripheral access. There should be expert clinical assessment of veins, and this evaluation may include ultrasound and/or near infrared evaluation. Conditions that would prompt a switch from PVA to an alternate method of venous access include loss of venous access, patient preference, or development of a requirement for very frequent treatment over a long period of time.

CONCLUSIONS

While PVA is not suitable for all patients requiring TPE, it has significant safety advantages over other approaches and should be employed whenever possible.

Therapeutic plasma exchange (TPE) for semi-critical neurology presentations in a non-acute neurology set-up: clinical practice and challenges

Introduction

Therapeutic plasma exchange (TPE) for semi-critical neurological manifestations can be managed in non-acute setting instead of critical care unit. In 2014, we established a non-acute neurology TPE unit for semi-critical haemodynamically stable patients. In this study, we aimed to evaluate the technical and safety parameters from the first 3 years of service.

Materials and methods

We analysed prospectively collected TPE data for patients treated with centrifugation TPE at our non-acute neurology TPE unit in Kuala Lumpur Hospital between May 2015 and June 2018.

Results

A total of 245 TPE procedures were performed in 55 patients for nine neurological indications, predominantly the central nervous system (79%). Twenty four per cent (n=13) had category I and 73% (n=40) had category II indication (American Society for Apheresis (ASFA) 2019). Others (4%) were not in ASFA indications. Neuromyelitis optica spectrum disorders accounted for half (51%) of the total patients. Twenty-three (41.8%) patients experienced adverse events, with hypotensive episodes being the the most common (n=12/55, 21.8%). Five (9.1%) patients had catheter-related blood stream infection, correlating with higher exchange plasma volume (p=0.023). Symptomatic hypocalcaemia was less common (n=5/55, 9.1%) and allergic reaction to human albumin was rare (n=1/55, 1.8%). Four technical errors detected. Three involved centrifugation sets manufacturing defects and one involved error in centrifugation set installation. Seven (2.9%) procedures were terminated: 5 for adverse effects and 2 for technical errors.

Conclusion

Performing TPE among semi-critical patients with neurology manifestations in basic non-acute set-up proved safe, with predictable complications. This set-up reduced the reliance on critical care services for TPE procedures.

Complications of therapeutic plasma exchange: A retrospective study of 1201 procedures in 435 children

Therapeutic plasma exchange (TPE) is now widely used in therapy of multiple diseases in children, by removing the plasma with pathogenic agents from patients. However, adverse reactions may limit its application.A retrospective cohort study of 435 hospitalized children treated with 1201 plasma exchange procedures between January 2013 and July 2018 were enrolled.Complications occurred in 152 procedures (12.7%); 90 procedures (7.5%) had ≥2 complications. No death occurred. The most common complications were pruritus and urticaria (7%), followed by hypertension (1.92%) and hypotension (1.17%). One child had an outbreak of disseminated cryptococcosis neoformans infection, another child developed anaphylactic shock, and 3 children presented toxic epidermal necrolysis after TPE. The incidence of pruritus and urticaria was higher in children of the 6∼15 year group (P < .05) compared with other age groups. There was no significant difference in the incidence of hypertension and hypotension in children at different ages and weights (P > .05). Compared with other diseases, anti-N-methyl-D-aspartate (anti-NMDA) receptor encephalitis led to a higher incidence of complications in children (P < .05).The results suggest that TPE is a relatively safe procedure for children, and most of the complications are mild. The most common complication is pruritus and urticaria. However, serious complications such as toxic epidermal necrolysis and infection should still be taken seriously.

Early Differentiation of Shiga Toxin-Associated Hemolytic Uremic Syndrome in Critically Ill Adults With Thrombotic Microangiopathy Syndromes

OBJECTIVES

Thrombotic microangiopathy syndromes are a heterogeneous group of severe diseases that often require ICU admission. Prompt initiation of targeted therapies is required for atypical hemolytic uremic syndrome and thrombotic thrombocytopenic purpura, whereas there is no specific consensus therapy for Shiga toxin-associated hemolytic uremic syndrome. We sought to compare the characteristics of Shiga toxin-associated hemolytic uremic syndrome, atypical hemolytic uremic syndrome, and thrombotic thrombocytopenic purpura patients at admission in the ICU to allow early differentiation of Shiga toxin-associated hemolytic uremic syndrome from other thrombotic microangiopathy syndromes and help to tailor initial treatment.

DESIGN

Retrospective cohort study.

SETTING

Two ICUs part of the French reference center for thrombotic microangiopathy syndromes.

PATIENTS

Adult patients presenting with features of thrombotic microangiopathy syndromes. Other causes than Shiga toxin-associated hemolytic uremic syndrome, atypical hemolytic uremic syndrome, and thrombotic thrombocytopenic purpura were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

From September 2003 to January 2017, 236 thrombotic microangiopathy syndrome patients were admitted, including 12 Shiga toxin-associated hemolytic uremic syndrome, 21 atypical hemolytic uremic syndrome, and 91 thrombotic thrombocytopenic purpura. Shiga toxin-associated hemolytic uremic syndrome patients were older than other thrombotic microangiopathy syndromes patients (64 yr [interquartile range, 50-72 yr] vs 42 yr [31-54 yr]; p = 0.007) and presented with more frequent digestive symptoms (92% vs 42%; p < 0.001), especially nonbloody diarrhea and vomiting. Biologically, Shiga toxin-associated hemolytic uremic syndrome patients displayed higher fibrinogen (490 mg/dL [460-540 mg/dL] vs 320 mg/dL [240-410 mg/dL]; p = 0.003) and creatinine levels (2.59 mg/dL [2.12-3.42 mg/dL] vs 1.26 mg/dL [0.61-1.90 mg/dL]; p < 0.001), and less marked anemia (hemoglobin level, 9.7 g/dL [8.7-11.9 g/dL] vs 7.7 g/dL [6.3-9.1 g/dL]; p < 0.001). Forty-two percent (n = 5) required renal replacement therapy, and 83% (n = 10) were treated with plasma exchange before the distinction from other thrombotic microangiopathy syndromes could be made.

CONCLUSIONS

Adult Shiga toxin-associated hemolytic uremic syndrome patients are older, present more frequently with digestive symptoms and display higher hemoglobin and fibrinogen levels than other thrombotic microangiopathy syndromes. However, overlap across the three thrombotic microangiopathy syndromes remains substantial, putting forward the need to implement early plasma therapy until thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome can be ruled out.

Immunological challenges and approaches to immunomodulation in Pompe disease: a literature review

Pompe disease is an autosomal recessive disorder caused by a deficiency of acid alpha-glucosidase resulting in intralysosomal glycogen accumulation in multiple tissue types, especially cardiac, skeletal, and smooth muscle. Enzyme replacement therapy (ERT) with alglucosidase alfa has led to improved clinical outcomes and prolonged survival in patients with Pompe disease. While ERT has changed the natural course of Pompe disease, with many long-term survivors, several factors affect the response to ERT. Previous studies in Pompe disease have shown that IgG antibodies to ERT can lead to a decline in muscle strength, pulmonary function, and overall and ventilator-free survival. Additionally, antibody responses to ERT can also cause hypersensitivity reactions. Various strategies to prevent or eliminate the IgG antibody response have been attempted in patients with Pompe disease. A detailed literature search was performed to compile data regarding the consequences of IgG antibodies, clinical approaches to prevent or eliminate IgG antibodies in patients with Pompe disease, and to expand our understanding of new modalities being developed in non-clinical settings. All qualifying articles describing the impact of IgG antibodies on the response to ERT, immunomodulation in patients with Pompe disease, and non-clinical settings identified via a PubMed database search were included in the review. Here, we provide a comprehensive review of combination- and single-agent therapies that have been investigated in the context of immune tolerance induction to ERT in Pompe disease to date. Immunomodulation strategies that successfully induce immune tolerance to ERT have improved overall survival, especially reflected in the decreased number of ventilator-dependent or deceased cross-reactive immunologic material (CRIM)-negative infantile Pompe disease (IPD) patients due to development of IgG antibodies when treated with ERT alone. Immunomodulation in CRIM-positive patients at the time they receive ERT also results in a decrease in the development of IgG antibodies compared to cases treated with ERT alone. Lessons learned from current approaches, alongside results from trials of novel immunomodulation strategies, may provide important insights into the development of next-generation therapies.

Membrane-filtration based plasma exchanges for atypical hemolytic uremic syndrome: Audit of efficacy and safety

BACKGROUND

While complement blockade with eculizumab is recommended as first-line therapy of atypical hemolytic uremic syndrome (aHUS), plasma exchanges (PEX) remain the chief option for anti-factor H (FH) antibody associated disease and when access to eculizumab is limited.

METHODS

We reviewed adverse events (AEs) and adverse outcomes (eGFR <30 mL/min/1.73 m² or death), in all patients with aHUS managed with membrane-filtration based PEX at one tertiary care center over 5.5 years.

RESULTS

During January 2013 to June 2018, 109 patients with aHUS (74 with antibodies to FH), aged median (range) 7.6 (0.5-18) year weighing 22.1 (6-90) kg, underwent 2024 sessions of PEX. AE, in 12.1% patients, were usually self-limiting and included chills (5.5%), vomiting/abdominal pain (3.3%), hypotension (1.6%), urticaria (1.5%), seizures (0.2%), hypocalcemia (0.2%), and hemorrhage (0.1%); plasma hypersensitivity and severe reactions were rare. Rate of catheter-related infections was 1.45/1000 catheter-days. Filter reuse (OR 1.69; 95% CI 1.26-2.26; P < .001) and >20 sessions of PEX/patient (OR 1.99; 95% CI 1.27-3.10; P = .002) were independently associated with adverse events; infusion of IV calcium gluconate during PEX was protective (OR 0.26; 95% CI 0.16-0.43; P < .001). Hematological remission was achieved in 96.3% patients after 6 (5-8) PEX sessions; 80.8% and 89.6% patients were dialysis independent by one and 3 months, respectively.

CONCLUSIONS

PEX is safe and associated with satisfactory short-term outcomes in children with aHUS. Prolonged PEX and filter-reuse are associated with complications.

The establishment of in-house neurology driven therapeutic plasma exchange infrastructure in a resource-limited public hospital in Malaysia: Adopting and integrating evidenced-based health care technology through time

There has been an increase in the use of therapeutic plasma exchange (TPE) in immune-mediated neurological disorders in recent years. However, accessibility and availability of TPE remains low and costly, especially for a country with limited healthcare funding like Malaysia. With expanding clinical indications in neurological disorders, and increasingly expensive conventional immunomodulatory treatment such as intravenous immunoglobulin and monoclonal antibodies, TPE remains an effective part of first or second-line treatment. In this article, we detailed the historical aspects of the use of TPE in neurological disorders in Malaysia over the last four decades and discussed the challenges behind the establishment of the first in-house neurology-driven TPE service in the country. Local TPE database from a national neurology centre in Kuala Lumpur over the past 20 years was analyzed. We observed a remarkable three folds increase in the use of TPE at our center over the past 10 years (total 131 TPE treatments) compared to a decade prior, with expanding clinical indications predominantly for central nervous system demyelinating disorders. Besides using membrane filtration method, centrifugal technique was adopted, providing new opportunities for other clinical beneficiaries such as a neurologist driven "in-house TPE unit". However, there were real world challenges, especially having to provide services with limited funding, human resources, and space. In addition, much has to be done to improve accessibility, availability, and sustainability of TPE services at our center and nationwide. Nevertheless, even with limited resources and support, it is possible with concerted efforts to work within the confines of these limitations to establish a safe, successful, and sustainable TPE service.

Therapeutic plasma exchange for the treatment of systemic sclerosis: A comprehensive review and analysis

Background

Therapeutic plasma exchange has been tried as a treatment approach for systemic sclerosis since 1978 based on the rationale that some circulating factor is involved in disease pathogenesis, for example, autoantibodies or immune complexes, and that removing the potential pathogenic factors could lead to symptom improvement. Based on our impression that clinicians and researchers are largely unaware that a large volume of research has been published about the use of therapeutic plasma exchange as a treatment for systemic sclerosis, we conducted a comprehensive review and analysis of all published research on this topic.

Results

We identified 46 relevant articles that met our search criteria, involving a total of 572 patients. Of these, 19 were case studies; the rest ranged from small observational studies to prospective randomized clinical trials. In all but two studies, most patients receiving therapeutic plasma exchange showed improvements in both clinical symptoms and laboratory markers, including significant improvement in Raynaud's symptoms and healing of digital ulceration after three to four weekly treatments. The beneficial effects from even a short course of therapeutic plasma exchange treatments were long-lasting, typically 6 months or longer. Therapeutic plasma exchange was very well tolerated. Adverse events were rare and, in almost all cases, mild and transitory.

Conclusion

These results suggest that long-term therapeutic plasma exchange may offer a low-risk way to control and in some cases reverse systemic sclerosis symptoms. The mechanism for the clinical improvements seen from therapeutic plasma exchange in systemic sclerosis patients is unclear. Therefore, additional studies of therapeutic plasma exchange effects in systemic sclerosis appear to be highly desirable.

Prevalent metabolic derangement and severe thrombocytopenia in ABO-incompatible liver recipients with pre-transplant plasma exchange

Desensitisation with therapeutic plasma exchange (TPE) is essential for ABO-incompatible (ABO-I) liver transplants (LTs). However, excessive citrate load and coagulation disturbances after TPE have been poorly studied, in particular in cirrhotic patients with hypocapnic alkalosis, metabolic compensation and electrolyte imbalances. We retrospectively evaluated 1123 consecutive LT recipients (923 ABO-compatible [ABO-C], 200 ABO-I) from November 2008 to May 2015. TPE was generally performed a day before LT and blood sampling was performed before anaesthesia induction. We performed propensity score matching (PSM) and inverse probability treatment weighting (IPTW) analyses. In 199 PSM pairs, metabolic alkalosis was prevalent in ABO-I LT recipients (expectedly due to citrate conversion) with higher pH ≥ 7.50 (IPTW-adjusted odds ratio [aOR] = 2.23) than in ABO-C LT recipients. With increasing cirrhosis severity, the arterial pH and bicarbonate levels showed dose-dependent relationships, whereas mild hypoxaemia was more prevalent in ABO-I LT recipients. ABO-I LT recipients exhibited worsened hypokalaemia ≤3.0 mmol/l (17.6%, aOR = 1.44), hypomagnesaemia ≤1.7 mg/dl (27.6%, aOR = 3.43) and thrombocytopenia <30,000/µl (19.1%, aOR = 2.26) confirmed by lower maximal clot firmness (P = 0.001) in rotational thromboelastometry (EXTEM), which necessitated platelet transfusions. Preoperative identification of these change may prevent worsening of severe electrolyte disturbances and thrombocytopenia for optimal LT anaesthesia.

Therapeutic plasma exchange: Experience in a third level hospital, 2013-2016, Lima (Peru)

BACKGROUND

Therapeutic plasma exchange (TPE) is an extracorporeal procedure which consists of removing the patient's plasma and replacing it with an appropriate replacement fluid. Plasma and blood cells are separated by a centrifugation process. Our department has used TPE for several years, and in 2013 we introduced an institutional apheresis protocol. The main objective of this report is to describe the TPE procedures performed between 2013 and 2016 in the Peruvian population.

METHODS

We analyzed the technical and clinical aspects of 864 centrifugal TPE procedures as well as the associated complications. We evaluated 230 patients treated in our institution.

RESULTS

The therapeutic indications included 16 different diseases: 89.5% (N = 206/230) neurological, 7.3% (N = 17/230) hematological, 1.7% (N = 4/230) rheumatologic, 0.8% (N = 2/230) dermatological and 0.4% (N = 1/230) nephrological. 70.4% (N = 142/230) of patients were diagnosed with Guillain-Barré syndrome. Albumin 5% solution was the most frequent replacement solution, used in 65.8% (N = 569/864) of the procedures. The mean plasma volume (PV) replaced was 2451.73 ml, corresponding to 1.0 PV in all procedures. Complications occurred in 10.9% (N = 95/864) of the sessions. Allergic reactions were the most common events and cardiopulmonary arrests were recorded in two patients.

CONCLUSION

This is the first report of TPE performed in the Peruvian population. The use of an institutional apheresis protocol was beneficial to improve registries in our service and our professional health attention. This study reports a low rate of complications, suggesting that TPE is safe. There is a need to create a multicenter Peruvian apheresis registry to assess the benefits and risks of TPE in Peru.

The management of anticoagulation in patients undergoing therapeutic plasma exchange: A concise review

We surveyed multiple apheresis centers represented by the authors for their clinical approach to the management of anticoagulation issues during therapeutic plasma exchange (TPE). We present the results of their practices and a review of the pertinent literature. As plasma is removed during TPE, replacement with all or partial non-plasma-containing fluids (eg, 5% albumin) may lead to significant changes in hemostasis. These changes are amplified in patients who are receiving anticoagulation. We discuss various anticoagulants as well as the monitoring and adjustment of anticoagulation before, during, and after TPE. No single guideline can be applied, but rather, patients must be monitored individually, taking into account their often complex clinical conditions and medication profiles.

Plasmapheresis and other extracorporeal filtration techniques in critical patients

Plasmapheresis is an extracorporeal technique that eliminates macromolecules involved in pathological processes from plasma. A review is made of the technical aspects, main indications in critical care and potential complications of plasmapheresis, as well as of other extracorporeal filtration techniques such as endotoxin-removal columns and other devices designed to eliminate cytokines or modulate the inflammatory immune response in critical patients.

An audit analysis of a guideline for the investigation and initial therapy of diarrhea negative (atypical) hemolytic uremic syndrome

BACKGROUND

In 2009, the European Paediatric Study Group for Haemolytic Uraemic Syndrome (HUS) published a clinical practice guideline for the investigation and initial therapy of diarrhea-negative HUS (now more widely referred to as atypical HUS, aHUS). The therapeutic component of the guideline (comprising early, high-volume plasmapheresis) was derived from anecdotal evidence and expert consensus, and the authors committed to auditing outcome.

METHODS

Questionnaires were distributed to pediatric nephrologists across Europe, North America, and the Middle East, who were asked to complete one questionnaire per patient episode of aHUS between July 1, 2009 and December 31, 2010. Comprehensive, anonymous demographic and clinical data were collected.

RESULTS

Seventy-one children were reported with an episode of aHUS during the audit period. Six cases occurred on a background of influenza A H1N1 infection. Of 71 patients, 59 (83 %) received plasma therapy within the first 33 days, of whom ten received plasma infusion only. Complications of central venous catheters occurred in 16 out of 51 patients with a catheter in-situ (31 %). Median time to enter hematological remission was 11.5 days, and eight of 71 (11 %) patients did not enter hematological remission by day 33. Twelve patients (17 %) remained dialysis dependent at day 33.

CONCLUSIONS

This audit provides a snapshot of the early outcome of a group of children with aHUS in the months prior to more widespread use of eculizumab.

Vascular access in therapeutic apheresis: update 2013

This review addresses the types of vascular access available for patients who need therapeutic apheresis (TA). As in hemodialysis, vascular access for TA is chosen based on type of procedure prescribed, the patient's vascular anatomy, the acuity, frequency and duration of treatment, and the underlying disease state. The types of access available include peripheral vein cannulation, central venous catheters: including nontunneled and tunneled catheters, arterio-venous grafts and arterio-venous fistulas. Peripheral veins and central venous catheters are most frequently utilized for the acute administration of TA, and may be used over a period of weeks to months. Arterio-venous grafts and fistulas are not commonly used in TA procedures, but are an option in patients with an anticipated long course of TA, usually for a period of several months or years. The types and frequency of complications associated with various types of vascular access, including: access dysfunction and infections are reviewed, and strategies for their prevention and management are offered.

Regional Citrate Anticoagulation in Therapeutic Plasma Exchange with Fresh Frozen Plasma - a Modified Protocol

Purpose

In membrane-based therapeutic plasma exchange (TPE), regional citrate anticoagulation (RCA) is associated with difficulties because of citrate accumulation and consequent, potentially significant, metabolic complications, especially when using fresh frozen plasma (FFP) as replacement fluid. We modified the technical setup of a commercially available continuous veno-venous hemodi-alysis RCA module (multiFiltrate Ci-Ca®) to establish an RCA-protocol for TPE.

Methods

Description of the modified technical setup and retrospective analysis of the feasibility of the RCA-protocol for TPE in all patients treated between 2009 and 2010.

Results

411 consecutive TPE with RCA were performed in 42 patients, all using FFP as replacement fluid. Median procedure characteristics were: blood flow 160 ml/min, filtrate flow 36 ml/min, duration 93 min, processed total plasma volume 3600 mL. Trisodium citrate was infused at a rate of 0.43 mmol/min to achieve post-filter ionized calcium levels of ≤0.4 mmol/l. Calcium substitution rate was 0.19 mmol/min to maintain physiologic iCa levels. RCA was well tolerated with no significant differences in pH, iCa, bicarbonate or potassium after repeated sessions. Clotting events complicated 7.3% of the procedures. Adverse events occurred in 3.4% of TPE procedures; none was severe or fatal. No significant differences were observed comparing the rate of adverse events to those observed in TPE using standard anticoagulation at our center (4.8%).

Conclusions

We describe for the first time a modified protocol for RCA in TPE using an integrated citrate module. Based on our experience, this RCA protocol is a feasible alternative for anticoagulation in TPE with FFP, especially in patients with a high risk of bleeding.