title: Paraneoplastic limbic encephalitis with prominent neuropsychiatric apathy.
abstract: The spectrum of paraneoplastic neurologic syndromes has increased with the description of encephalitis associated with antibodies against cell surface and synaptic proteins. Subacute cognitive impairment, movement disorders, late onset epilepsy and neuropsychiatric syndromes were recently linked to paraneoplastic encephalitis. Despite that, probably some syndromes and antibodies are yet to be reported. Herein we reported the clinical and neuroimaging pictures of a patient with late onset medial temporal lobe epilepsy, subtle cognitive impairment, psychosis and severe apathy diagnosed with antibody-negative paraneoplastic encephalitis due to colonic adenocarcinoma. The apathy markedly improved after removal of the tumor, without concomitant immunotherapy (steroids, intravenous immunoglobulins, immunosuppressants, plasmapheresis, etc.). Our report highlights the importance of a full clinical and neurologic investigation in cases of atypical neuropsychiatric presentations, particularly in the elderly and with the concomitance of epilepsy and cognitive decline. Even chronic presentations must be considered. Neuroimaging is an important tool to demonstrate structural and functional brain dysfunction in these cases. Colonic adenocarcinoma should be searched for in cases in which a typical tumor related to paraneoplastic neurologic syndromes is not found.
authors.affiliation: Behavioral and Cognitive Neurology Unit, Department of Neurology, Cognitive Disorders Reference Center (CEREDIC), University of São Paulo, São Paulo, SP, Brazil. Electronic address: portofhg@gmail.com.
authors.forename: Fábio Henrique de Gobbi
authors.initials: FH
authors.lastname: Porto
authors.affiliation: Department of Radiology, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Artur Martins Novaes
authors.initials: AM
authors.lastname: Coutinho
authors.affiliation: Department of Radiology, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Leandro Tavares
authors.initials: LT
authors.lastname: Lucato
authors.affiliation: Behavioral and Cognitive Neurology Unit, Department of Neurology, Cognitive Disorders Reference Center (CEREDIC), University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Lívia
authors.initials: L
authors.lastname: Spíndola
authors.affiliation: Department of Radiology, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Carla Rachel
authors.initials: CR
authors.lastname: Ono
authors.affiliation: Behavioral and Cognitive Neurology Unit, Department of Neurology, Cognitive Disorders Reference Center (CEREDIC), University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Sonia Maria Dozzi
authors.initials: SM
authors.lastname: Brucki
authors.affiliation: Department of Radiology, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Buchpiguel
authors.affiliation: Behavioral and Cognitive Neurology Unit, Department of Neurology, Cognitive Disorders Reference Center (CEREDIC), University of São Paulo, São Paulo, SP, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Nitrini
mesh_terms: D057565:Apathy; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D019788:Fluorodeoxyglucose F18; D006801:Humans; D020363:Limbic Encephalitis / Q000150:complications* / Q000175:diagnosis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020361:Paraneoplastic Syndromes, Nervous System / Q000150:complications* / Q000175:diagnosis; D049268:Positron-Emission Tomography
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: Amygdalar enlargement; Apathy; Atypical neuropsychiatric syndromes; Colonic adenocarcinoma; Limbic encephalitis; Paraneoplastic neurologic syndrome