Management of renal disorders

Plasma-exchange in Chronic Peripheral Neurological Disorders

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases.

Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE. Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy.

In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.

American Society for Apheresis guidelines on the use of apheresis in clinical practice: practical, concise, evidence-based recommendations for the apheresis practitioner

The 6th Guidelines on the use of therapeutic apheresis in clinical practice published by the American Society of Apheresis provide practical, concise, and evidence based guidance for the apheresis medicine practitioner. The overall format of the Guidelines has remained unchanged with the 6th edition, compared to the 5th edition, with enhancements in the committee process of creating the guidelines. Because of changes in the writing committee structure, a number of changes have occurred in the ASFA category and recommendation grade for the use of apheresis in the treatment for a number of previously categorized clinical indications. In addition, eight new indications for apheresis, twenty three new clinical situations for previously categorized diseases, and ten new apheresis treatments for previously categorized disorders have been added. The 6th Guidelines continue to be an invaluable resource for those involved in apheresis medicine.

Treatment of antibody-mediated accelerated rejection using plasmapheresis

Accelerated antibody-mediated rejection is believed to be due to an anamnestic response of an allograft recipient to donor antigens. Few reports have demonstrated successful reversal of this type of rejection, and no consensus exists for either diagnosis or treatment. Accelerated antibody-mediated rejection was suspected on the basis of clinical findings and confirmed by cytotoxic and flow crossmatches, and leukocyte antibody screens. Serial crossmatches and antibody screens were performed through post-transplant day 112. Plasmapheresis was performed on post-transplant days 1, 2, 4, 6, 12, 14, 20, and 28. The duration of treatment was determined by the cytotoxic crossmatch results. We present a case of successfully treated accelerated antibody-mediated rejection using plasmapheresis and aggressive immunosuppression. Serial crossmatch and leukocyte antibody screen results are presented that confirm the production of anti-donor antibody and demonstrate the effectiveness of the treatment protocol in eliminating detectable levels of the anti-donor antibody. At 6 months post-transplant, the patient has a serum creatinine of 1.1 and has not had any additional rejection episodes or infectious complications. The protocol suggested in this paper allows for rapid diagnosis, institution of treatment, and monitoring the efficacy of treatment, providing the basis for follow-up clinical trials.

Treatment of thrombotic thrombocytopenic purpura: a role for early vincristine administration

Plasma exchange (PE) is considered first-line treatment for thrombotic thrombocytopenic purpura (TTP) to the point that many clinicians regard it as definitive therapy. Studies have reported response rates to PE ranging from 39% to 78%. In our experience, a minority of patients have been cured solely by PE. While adjuvant therapies (e.g., vincristine, splenectomy) have proved effective in anecdotal reports, protocols using these therapies in the treatment of TTP have not been established. Management of TTP over a 15-year period was reviewed to evaluate (1) the rate of cure accomplished by PE alone, and (2) the potential benefit of additional therapies. The records of 29 consecutive patients with TTP treated by PE were reviewed and classified according to response to PE alone and the need for adjuvant therapy. Eight patients (28%) achieved remission and long-term survival with PE alone. With the addition of adjuvant therapy another 13 patients survived, bringing the total survival to 72%. Fifteen patients were treated with vincristine in addition to PE. Only three of seven patients receiving vincristine after failing to respond completely to PE survived, but survival increased to 88% (7 of 8) when vincristine was administered within 3 days of beginning PE. These data suggest that PE alone may not be sufficient therapy for most patients with TTP. Additional therapy is often needed to achieve long-term survival. While controlled trials will be necessary to prove the efficacy of vincristine, we believe that, given the minimal risk of vincristine toxicity and the grave consequences of ineffective therapy, routine administration of vincristine early in the course of PE should be considered.

Cholesterol biosynthesis in normocholesterolemic patients after cholesterol removal by plasmapheresis

Plasmapheresis and low-density lipoprotein (LDL)-apheresis are recognized procedures for the treatment of hyperlipidemia resistant to diet and lipid-lowering drugs and provide information on cholesterol synthesis in hypercholesterolemic patients. However, cholesterol synthesis after acute cholesterol removal from plasma has never been investigated in normocholesterolemic patients. In this study, cholesterol synthesis was evaluated in three normocholesterolemic patients by determination of plasma lathosterol, lathosterol-to-cholesterol ratio, and plasma mevalonic acid. In a short-term kinetic study, samples were collected before and after plasmapheresis and every 6 hours during 24 hours. In the second part of the study, cholesterol synthesis was evaluated daily for 3 days. In normocholesterolemic patients, cholesterol returns to basal levels in 3 days. However, cholesterol removal did not result in a significant increase in lathosterol-to-cholesterol ratio or in plasma mevalonic acid, despite a slight increase in lathosterol. In contrast, when repeated plasma exchanges induced a dramatic hypocholesterolemia (< 1 mmol/liter), an acute but transient stimulation of cholesterol synthesis was observed (lathosterol/cholesterol ratio and MVA, respectively, increase from 8.2 to 22.3 and from 28 nmol/liter to 98 nmol/liter). This study shows that cholesterol synthesis is not stimulated by plasmapheresis in normocholesterolemic patients but is enhanced in dramatic hypocholesterolemic patients (< 1 mmol/liter).

United States Thrombotic Thrombocytopenic Purpura Apheresis Study Group (US TTP ASG): multicenter survey and retrospective analysis of current efficacy of therapeutic plasma exchange

Thrombotic thrombocytopenic purpura (TTP) remains enigmatic from the perspective of its etiology, pathophysiology, and treatment. Once recognized, the accepted standard of care for TTP is daily therapeutic plasma exchange (TPE). However, the diversity in TPE treatment protocols has made comparisons of clinical research between institutions difficult. This study strived to assess the current practice of TPE in order to provide direction for prospective controlled clinical trials. Twenty large apheresis centers within the United States comprising the US TTP ASG responded to a survey to establish the current status of TPE in TTP. A retrospective analysis from data provided by 14 of 20 centers included 115 initial presentations of primary TTP with an overall mortality rate of 10% and relapse rate of 37%. The majority of deaths (58%) occurred within 48 hours of presentation. Variation in therapeutic targets (platelet count [plt] and serum LDH) and the number of plasma volumes exchanged per procedure did not affect the relapse rate. Initial plt and LDH were not predictive of mortality. Response, relapse, and mortality rates with the combination of 5% albumin for the initial 50% of TPE followed by plasma for the final 50% of TPE as replacement were comparable or possibly better than plasma-only replacement strategies. Forty percent of centers routinely used a TPE taper; however, there was no statistical difference in relapse rates comparing the taper and non-taper sub-groups. By controlling for adjunctive modalities such as steroids and anti-platelet agents, it is hoped that future prospective clinical trials may optimize the role of TPE in TTP, minimize patient exposure to blood products and procedures, shorten the clinical course of TTP, and reduce mortality.

Apheresis and the thrombotic thrombocytopenic purpura syndrome: current advances in diagnosis, pathophysiology, and management

Endeavors to optimize the management of thrombotic thrombocytopenic purpura (TTP) syndrome and improve mortality and relapse rates are hindered by its poorly understood pathophysiology. Variability in the application of therapeutic plasma exchange (TPE), including replacement fluid strategies, desirable endpoints in the platelet count, serum lactate dehydrogenase concentration, and the use of a TPE taper, limit comparisons among published studies. The diversity of adjunctive therapies such as antiplatelet agents, steroids, and splenectomy further clouds comparisons. Recent progress in the diagnosis, pathophysiology, and management of TTP syndrome are summarized. The possible role of occult infection and newly emerging associations such as ticlopidine therapy are discussed. Advances in possible pathogenic mechanisms, the rationale for different replacement fluids including the recently licensed solvent-detergent treated plasma, and progress in the apheresis management of TTP syndrome are presented.

Indications for emergency apheresis procedures

Therapeutic apheresis has gained tremendous popularity worldwide in the last 2 decades. Emergency procedures can be life saving but should be undertaken for limited indications. Our emergency indications and experiences since the 1970s are critically described.

Plasma-Exchange in Chronic Peripheral Neurological Disorders

We investigated 19 patients affected by chronic peripheral neurological disorders treated with therapeutic plasma exchange (TPE) to verify the efficacy of the therapeutic protocol used in these diseases.

Every patient was clinically considered after 5 TPE. Those who showed an improvement started chemotherapy and continued TPE at the rate of 2 procedures/week for 2 weeks, then 1 procedure/week for 1 month and finally 1 procedure every 2 weeks for 2 months. Intravenous immunoglobulins (IVIg) were infused at the end of apheretic treatment in one of the patients affected by neurological disorders due to monoclonal gammopathy undetermined significance. HCV-positive patients with cryoglobulins were treated with α-interferon (α-IFN) for 6 months before TPE.

Eleven patients (58%) had a symptomatic improvement, 2 (1.5%) stopped TPE treatment owing to side effects and 6 (31.5%) did not respond to apheretic therapy.

In order to improve the advantages of TPE we suggest using IVIg at the end of apheretic therapy, while in HCV-positive patients, at least one year of α-IFN therapy is required before initiating TPE.

Therapeutic plasma exchange for the treatment of rapidly progressive glomerulonephritis

Therapeutic plasma exchange (TPE) has been widely accepted as a successful means of removing the antiglomerular basement membrane (anti-GBM) antibodies that result in the rapidly progressive glomerulonephritis (RPGN) of Goodpasture's syndrome. TPE has also been investigated as a means of removing the immune complexes associated with the glomerulonephritides of systemic lupus erythematosus, IgA nephropathy, Henoch Schönlein purpura, and cryoglobulinemia. Recently, an antineutrophil cytoplasmic antibody (ANCA) has been implicated in the pathogenesis of RPGN associated with such diseases such as Wegener's granulomatosis and periarteritis nodosa. ANCA has also been found in many cases of RPGN formally considered to be idiopathic. The identification of this autoantibody has given new credence to the possibility that TPE may be beneficial in the treatment of these diseases. This article reviews the data regarding the use of TPE for RPGN.