It is extremely important to begin treatments as soon as possible after a rare neuroimmune diagnosis. Treatment in the acute or early stages involves quieting down the immune system as quickly as possible, before damage is done. Time is critical.

The acute therapies most frequently used to treat an inflammatory attack include: high dose intravenous steroids (methylprednisolone), Plasmapheresis (Plasma Exchange or PLEX), Immunoglobulin Therapy (IVIG), and cyclophosphamide.^19,35

Intravenous Steroids

Intravenous steroid treatment is the first line of therapy often used in acute TM. Corticosteroids have multiple mechanisms of action including anti-inflammatory activity, immunosuppressive properties, and antiproliferative actions. Though there is no randomized double-blind placebo-controlled study that supports this approach, evidence from related disorders and clinical experience support this treatment. The standard of care includes intravenous methylprednisolone (30 mg/kg up to 1000 mg daily) or dexamethasone (120 to 200 mg daily for adults) for 3 to 5 days unless there are compelling reasons to avoid this therapy.¹⁹ The decision to offer continued steroids or to add a new treatment is often based on the clinical course and MRI appearance at the end of 5 days of steroids.^19,34

Plasma Exchange (PLEX)

PLEX is often initiated in individuals with motor impairment³⁶ or who show little clinical improvement after intravenous steroid treatment,^37-39 but may also be initiated at first presentation for those with significant deficits.¹⁹ It is often given as five treatments, each with exchanges of 1.1 to 1.5 plasma volumes, every other day for 10 days.⁴⁰ PLEX is believed to work in autoimmune CNS diseases through the removal of specific or nonspecific soluble factors likely to mediate, be responsible for, or contribute to inflammatory-mediated organ damage. PLEX has been shown to be effective in adults with TM and other inflammatory disorders of the CNS.

Other Immunomodulatory Treatment

If there is continued progression despite intravenous steroid therapy and PLEX, pulse dose intravenous cyclophosphamide (800–1200 mg/m²) is considered.¹⁹ Cyclophosphamide is known to have immunosuppressive properties. From the Johns Hopkins TM Center experience, it has been reported that PLEX provided an added benefit to steroids in patients who were not at a disability level of ASIA A and who did not have a history of autoimmune disease. For those who were classified at a disability level of ASIA A at their nadir, they showed a significant benefit when given combination therapy with steroids, PLEX and IV cyclophosphamide.³⁵ Cyclophosphamide should be administered under the supervision of an experienced oncology team, and caregivers should monitor the patient carefully for hemorrhagic cystitis and cytopenias.

Another option for treating acute inflammation is intravenous immunoglobulin (IVIG). Immunoglobulin comes from pooled blood that is donated from thousands of healthy people. As the name suggests, IVIG is given intravenously. IVIG is generally well-tolerated. Potential adverse reactions are uncommon, but usually occur during or immediately after an infusion and include headache, nausea, muscle pain, fever, chills, chest discomfort, skin and anaphylactic reactions. Reactions after an infusion can be more serious and include migraine headaches, aseptic meningitis, renal impairment and blood clots. Like corticosteroids and PLEX, there are no data confirming the value of IVIG in the setting of acute events. While most studies support the use of corticosteroids and/or PLEX in acute demyelinating syndromes, IVIG can be considered in certain circumstances.

Recurrence of idiopathic TM is rare and warrants a comprehensive evaluation for known causes of recurrent myelitis. Consultation with a neuroimmunologist should strongly be considered when recurrence occurs, and immunosuppressive treatments may be recommended.