Optimizing management of replacement fluids for therapeutic plasma exchange: Use of an automated mathematical model to predict post-procedure fibrinogen and antithrombin levels in high-risk patients

Apheresis treatment in autoimmune neurological diseases: Predictors of good clinical outcome and success of follow-up therapy with B-cell depletion

OBJECTIVE

Apheresis treatment (AT) is an established standard of treatment in various neurological autoimmune diseases. Since not all patients equally benefit from AT, we saw the need to investigate the effect of different clinical, paraclinical and technical-apparative factors on the clinical outcome. Additionally, we wanted to find out whether patients who improved due to AT continue to be clinically stable under B-cell depletion (BCD).

METHODS

We screened all patients (n = 358) with neurological diseases who received AT at the Medical center of the University of the Saarland in the past 20 years. Different factors (e.g., age, sex, duration until onset of AT, type of AT, number of cycles, csf parameters) were analyzed retrospectively. Clinical disability was measured using the modified Rankin scale (mRS), visual acuity and the Expanded Disability Status Scale (EDSS).

RESULTS

335 patients, categorized into 11 different autoimmune diagnosis groups, received a total of 2669 treatment cycles and showed a statistically significant improvement in mRS with AT (p < 0.001). Patients in American Society for Apheresis (ASFA) categories I (p = 0.013) and II (p = 0.035) showed a significantly greater benefit under AT than those in category III. The clinical outcome was better with shorter duration until AT onset, more cycles of AT, and more plasma volume exchanged and the presence of an autoimmune antibody. Patients who initially profited had a significantly more stable course of the disease after 1-Year-BCD (p = 0.039).

DISCUSSION

In the present study, we were able to identify various significant factors influencing the outcome of patients due to AT. Furthermore, we could show that patients with a response to AT can benefit from BCD follow-up therapy.

Hemostatic effects of therapeutic plasma exchange: A concise review

Therapeutic plasma exchange (TPE) alters the hemostatic balance. Contributing to TPE's hemostatic effects is the mechanical processing of blood in the extracorporeal circuit, circuit anticoagulant, type of replacement fluid, TPE schedule and number of procedures, TPE timing relative to invasive procedures, and removal of nontargeted components such as platelets, coagulation proteins, and cytokines. Although TPE's hemostatic effects are well established, how it impacts the bleeding risk is not clearly understood. In this concise review, we describe the effects of the above TPE-related factors on hemostatic balance, present data on the effects of TPE on blood hemostasis, including its effects on platelet counts and clotting assays, and review the literature on the impact of TPE-induced hemostatic changes on TPE-associated bleeding events. Finally, we discuss risk factors associated with bleeding during TPE and review the literature on TPE-associated hemostatic effects in the pediatric population.