PracticeUpdate: Neurology - Winter 2018

CONFERENCE COVERAGE 22

Significant Progress Has BeenMade in Immune-Mediated Neuropathies The field of treatable, immune-mediated neuropathies is expanding T he understanding of immunobiology, discovery of new anti- bodies, and evaluation of new diagnostics have opened the way to new treatments for patients with these disorders, con- cluded a presentation at ICNMD 2018.

• Development of more complications, possibly related to the second IV immune globulin treatment • Reduced mortality due to Guillain-Barré syndrome • Whether serum immune globulin increase after the first IV immune globulin dosage will be lower in individuals with poor prognosis • Whether serum immune globulin G increases further (and to what extent) after administration of a second IV dose Inclusion criteria are: • Diagnosis of Guillain-Barré syndrome according to internation- ally accepted criteria • Grade 3, 4, or 5 on the Guillain-Barré syndrome disability scale or other indication for IV immune globulin therapy according to the treating neurology Dr. van Doorn mentioned, “An alternative, simple treatment for Guil- lain-Barré syndrome, small-volume plasma exchange, was evaluated in an interesting new study. Small-volume plasma exchange may be especially helpful in low-income countries.” Intravenous immunoglobulin and plasma exchange are effective in Guillain-Barré syndrome. An indication now exists that inhibition of complement activation using eculizumab is potentially effective in Guillain-Barré syndrome, though additional studies are needed. Individuals within the CIDP spectrum can be treated with IV immune globulin, plasma exchange, or steroids. If one of these proven effective treatments fail, one of these other treatments are still likely to be successful. A recent randomized controlled trial showed that individuals with CIDP can also be treated with subcutaneous immune globulin. The best treatment for CIDP is debated. IV immune globulin works rapidly but is expensive. Steroids are inexpensive but can induce major side effects. Pulse steroid treatment, however, may be more likely to induce disease remission and is under investigation. Under- and over- treatment in individuals with immune-mediated neuropathies are important problems. Whether an individual still requires treatment (response can be either therapeutically induced or be due to the nature of the disease) needs to be determined at least every 6 to 12 months. Multifocal motor neuropathy may mimic motor neuron disease, but is treatable with IV immune globulin. Surprisingly, individuals with multifocal motor neuropathy do not improve with steroids or plasma exchange. Other important immune-mediated neuropathies are related to the presence of a paraprotein or are caused by, for example, vasculitis. Dr. van Doorn concluded, “Amazing progress has been made in the understanding of immunobiology, discovery of new antibod- ies, and evaluation of new diagnostics. These have helped identify (new) subgroups and have opened the way to new treatments for patients with these disorders.” www.practiceupdate.com/c/70779 • <2 weeks since the onset of weakness • Ability to attend the 6-month follow-up visit

Dr. Pieter A. van Doorn Pieter A. van Doorn, MD, PhD, of the Erasmus Medical Center in Rotterdam, The Nether- lands, discussed the expanding field of treatable, immune-mediated neuropathies. Dr. van Doorn explained that immune- mediated neuropathies are an extending field of disorders with specific subgroups. Individuals with these disorders need to be diagnosed because their conditions are treatable. Immune-mediated neuropathies range from the heterogeneous acute polyneuropathy Guillain-Barré syndrome to the more chronic, often demyelinating, polyradiculoneuropathies. Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most prominent immune-mediated neuropathy. CIDP can be divided into the most frequent symmetric sensory-motor variant and pure motor or sensory subgroups. Focal or multifocal varie- ties of CIDP are known as Lewis-Sumner syndrome or multifocal acquired demyelinating sensory-motor neuropathy. A variety termed distal acquired demyelinating sensory neurop- athy is also reported. Careful electrophysiological investigation and peripheral nerve high-definition ultrasonography or MRI of the plexus can be helpful in diagnosing these individuals. European Academy of Neurol- ogy/Peripheral Nerve Society guidelines for the diagnosis and treatment of Guillain-Barré syndrome and CIDP are available or under construction. Dr. van Doorn told Elsevier’s PracticeUpdate , “Results of the large, randomized, controlled Second IVIg Dose trial in patients with GBS with a poor prognosis (SID-GBS) trial are eagerly awaited and will likely be available in early 2019. Poor prognosis was based on results of the modified Erasmus GBS Outcome Score (mEGOS).” The primary objective of the SID-GBS trial is to determine whether a second IV immune globulin dose in individuals with Guillain-Barré syndrome with a poor prognosis improves functional outcome after 4 weeks. Secondary objectives are to evaluate: • Functional outcome or muscle strength after 8, 12, and 26 weeks • The percentage of individuals needing artificial ventilation and less time (number of days) on a respirator or in intensive care • Reduction in time to hospital discharge • Reduction in risk of secondary deterioration due to treatment-re- lated fluctuations " Results of the large, randomized, controlled Second IVIg Dose trial in patients with GBS with a poor prognosis (SID-GBS) trial are eagerly awaited and will likely be available in early 2019. "

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