Anti-LGI1-associated cognitive impairment: Presentation and long-term outcome.
Neurology. 2016-07-27; 87(8): 759-765
DOI: 10.1212/wnl.0000000000003009
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Ariño H(1), Armangué T(1), Petit-Pedrol M(1), Sabater L(1), Martinez-Hernandez E(1), Hara M(1), Lancaster E(1), Saiz A(1), Dalmau J(1), Graus F(2).
Author information:
(1)From the Neuroimmunology Program (H.A., T.A., M.P.-P., L.S., E.M.-H., M.H., A.S., J.D., F.G.), August Pi Sunyer Biomedical Research Institute (IDIBAPS), Hospital Clínic, University of Barcelona, Spain; Department of Neurology (E.L., J.D.), University of Pennsylvania, Philadelphia; and Catalan Institution for Research and Advanced Studies (ICREA) (J.D.), Barcelona, Spain.
(2)From the Neuroimmunology Program (H.A., T.A., M.P.-P., L.S., E.M.-H., M.H., A.S., J.D., F.G.), August Pi Sunyer Biomedical Research Institute (IDIBAPS), Hospital Clínic, University of Barcelona, Spain; Department of Neurology (E.L., J.D.), University of Pennsylvania, Philadelphia; and Catalan Institution for Research and Advanced Studies (ICREA) (J.D.), Barcelona, Spain. .
OBJECTIVE: We investigated a series of patients with LGI1 antibody (Ab)-related
cognitive deterioration to determine the clinical presentation, long-term
outcome, and LGI1 Ab evolution.
METHODS: We retrospectively analyzed the clinical information of 76 patients with
LGI1 Ab-related cognitive deterioration. Presenting syndromes were classified as
limbic encephalitis (LE), non-LE, or encephalopathy (normal MRI and no CSF
pleocytosis). Frequency of relapses and clinical outcome were assessed in 48
patients with prolonged follow-up (median 39 months, range 18-200).
RESULTS: Sixty-three patients (83%) developed LE, 3 (4%) non-LE, and 10 (13%)
encephalopathy. All patients received steroids, IV immunoglobulins (Ig), or both.
At 2 years, 17 (35%; 95% CI 21%-49%) fully recovered, 17 (35%) became
functionally independent but not at baseline or were unable to return to work, 11
(23%) required assistance because of moderate or severe cognitive deficits, and 3
(6%) died. Predictors of bad outcome included no response to initial
immunotherapy (odds ratio 23.0, 95% CI 2.4-215.6, p = 0.006) and clinical
relapses (odds ratio 10.2, 95% CI 1.0-100.1, p = 0.047) that occurred in 13
patients (27%). In all patients, the LGI1 Abs were IgG4 and usually detectable in
both serum and CSF (only CSF, 8%). Abs remained positive in serum of 4 of 16
patients with long-term follow-up; 3 of these 4 patients fully recovered and none
showed class switch to IgG1.
CONCLUSIONS: Up to 13% of patients with LGI1 Abs develop cognitive impairment
without criteria of encephalitis. After immunotherapy, only 35% of patients
return to their baseline cognitive function. Serum LGI1 Abs may remain detectable
after full clinical recovery.
© 2016 American Academy of Neurology.