Autoimmune encephalitis and immune therapy: lessons from Argentina

Abstract

Autoimmune encephalitis (AE) is a common cause of noninfectious acute encephalitis. We aimed to provide the first review of immune therapy regimens used for patients with AE in Latin America, as well as the safety and efficacy associated with them, by reviewing the medical records of Argentine patients with AE treated between 2013 and 2018. Data included clinical symptoms, laboratory tests, electroencephalography, magnetic resonance imaging, cerebral spinal fluid, and neoplasm screenings. We examined ten AE patients who received first-line immunotherapy at a median of 2.5 months following symptom onset. Among these patients, five required second-line treatment: three received therapy at a median of 4 months (2-112) after symptom onset and were treated with rituximab, while two received therapy at a median of 4.5 (4-5) months after onset and received methylprednisolone for 6 months and initiated chronic treatment with azathioprine. By the last follow-up, their respective outcomes improved significantly. On the modified Rankin Scale, the median score decreased from 5 to 1 (p ≤ 0.05). Only two of the ten patients in our series experienced relapses; both had been treated with a combination of methylprednisolone and IVIG. The regimen after recurrence included rituximab and corticoids plus azathioprine. Neither patient had experienced another relapse by their last follow-up. Our findings demonstrate the importance of early and aggressive immunosuppressive therapy to achieve a good clinical outcome and a fast recovery without relapses.

Clinical Characteristics and Outcome of Neuronal Surface Antibody-Mediated Autoimmune Encephalitis Patients in a National Cohort

“…In a cohort of Chinese patients, relapses were also uncommon, occurring in 7/86 (8.1%) AE patients, mainly affecting NMDAR patients (5/72, 6.9% of anti-NMDAR patients) (12). However, in a cohort of Argentine AE patients 25% of anti-NMDAR patients had relapses, but relapses also occurred in 25% of anti-LGI1 patients (15). Majority of the patients received firstline immunotherapy, steroid solely, or in combination with intravenous immunoglobulin or plasmapheresis, which had a good curative effect in most AE patients.…”

“…Complete recovery was assessed in AE patients with mRS score of 0 at the last visit following treatment (median: 33 months; range: 1-77) (12). Relapse was defined as the new onset or worsening of symptoms, after at least 2 months of improvement or stabilization (15).…”

Clinical Characteristics and Short-Term Prognosis of Autoimmune Encephalitis: A Single-Center Cohort Study in Changsha, China

“…The cure rate of AE was defined as the proportion of patients with mRS of 0 at the longest follow-up after treatment. Relapse of AE was defined as new onset or worsening of symptoms, occurring after at least 2 months of improvement or stabilization (8).…”

Autoimmune Encephalitis in Latin America: A Critical Review

“…The modified ranking scale (mRS) score at last documented follow-up assessment was reported for 43 patients in 4 studies. Of those, 23 patients had an mRS score of 0, 12 patients had an mRS score of 1, two patients had an mRS score of 2, three patients had an mRS score of 3, two patients had an mRS score of 4, and one patient had an mRS score of 6 (3,(5)(6)(7)). An mRS ≤ 2 has been achieved in 86% of patients.…”

“…According to four studies included in this review, which add up to 43 patients, scores on the modified ranking scale (mRs) at the last evaluation during follow-up revealed that what has been considered as a "good outcome" (mRs ≤ 2) in previous reports has been achieved in the majority of patients (N = 37; 86.05%) (3,(5)(6)(7). This is consistent with larger data from international literature where an mRs ≤ 2 was achieved in 78.64% of patients (18).…”