Anti-N-methyl-d-aspartate receptor encephalitis causing a prolonged depressive disorder evolving to inflammatory brain disease.
BACKGROUND
Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a rapidly evolving condition that combines psychiatric and neurologic manifestations. Much remains unclear about its clinical onset and subsequent course. Although successful treatment depends on diagnosing the disorder early and therefore minimizing long-term complications, this is a difficult task owing to the atypical onset of this condition and the prolonged clinical course that has been observed in some patients. This report, illustrating a patient with slowly progressing psychiatric manifestations, unusual imaging and electrophysiological features, extends the information on varied clinical phenotypes.


METHODS
A 32-year-old woman suffered from an isolated depressive disorder for 4 months before undergoing psychiatric evaluation. During the following 5 months, she manifested hypersexuality, dysarthria, imbalance, dyskinesias and decreased word output. Brain magnetic resonance imaging (MRI) showed multifocal hyperintense T2/FLAIR lesions, a few contrast-enhanced, involving the corona radiata, the periventricular white matter, the deep gray nuclei, the optic nerves and the brainstem. MRI spectroscopy disclosed confluent bilateral demyelination and focal optic nerve involvement suggesting widespread encephalitis. Visual evoked potential studies indicated a demyelinating disorder. Serological screening and total body positron-emission tomography yielded negative findings for malignancies. Cerebrospinal fluid examination disclosed IgG oligoclonal bands and anti-NMDAR antibodies. Corticosteroids and intravenous immunoglobulin provided only slight improvement, whereas switching to cyclophosphamide markedly improved her neurological status.


CONCLUSIONS
In patients with a prolonged clinical course, including psychiatric and neurological symptoms, the differential diagnosis should be anti-NMDAR encephalitis. This report expands the known disease phenotypes in this emerging condition.
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Sara
S
Mariotto
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Stefano
S
Tamburin
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Alessandro
A
Salviati
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Sergio
S
Ferrari
Department of Neurology, Regional Hospital 'Ca' Foncello', Treviso, Italy.
Marco
M
Zoccarato
Department of Neurology, Regional Hospital 'Ca' Foncello', Treviso, Italy.
Bruno
B
Giometto
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Laura
L
Bertolasi
Division of Neuroradiology, AOUI, Verona, Regional Hospital 'Ca' Foncello', Treviso, Italy.
Franco
F
Alessandrini
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Maria Donata
MD
Benedetti
Department of Neurological and Movement Sciences, University of Verona, Treviso, Italy.
Salvatore
S
Monaco
Anti-N-methyl-D-aspartate receptor encephalitis; Depressive disorder; Optic neuritis