Treating Autoimmune Encephalitis

Autoimmune encephalitis is diagnosed using neural antibody biomarkers. But there is little data on the serology, clinical course and complications and outcomes among the most critically ill patients.

In an abstract presented April 19 at the American Academy of Neurology 2015 annual meeting in Washington, DC, Andrew McKeon, MD, a neurologist at the Mayo Clinic in Rochester, MN, reported on patients with the condition treated there. “It is an eminently treatable disorder,” McKeon wrote.

All the patients studied were in intensive care.

Initial symptoms included seizures, confusion, subacute cognitive or behavioral decline and cranio-cervical pain. Of a total of 635 patients, 28 showed immunological findings suggesting the condition was caused by auto-immune factors. Thirteen of the patients were seropositive for IgG responses, ANNA1, Ma1/Ma2 antibodies, or PCA-1. Fifteen patients had another antibody type, an inflammatory cerebrospinal fluid, coexisting autoimmune disease, and immunotherapy response, an encephalitic-appearing MRI or concomitant cancer diagnosis.

Of 12 patients who were cared for in intensive care for at least 3 days, those who showed improvement were treated with plasmapheresis, corticosteroids, or rituximab. Complications included anemia, sepsis, pulmonary edema, venous thrombosis, sympathetic hyperactivity, and refractory seizures.

At 3-month followup, 10 patients had died, but 10 had significantly improved and 8 had mild or no disability.

The authors concluded “Autoimmune encephalitis needs to be considered in neural antibody negative cases” and that “even when severe, good outcomes may occur in ICU-managed autoimmune encephalitis patients” as long as they are diagnosed quickly.