Paraneoplastic Encephalopathy Presenting with Rapidly Progressive Dementia and Catatonia

Abstract

Introduction: Paraneoplastic encephalopathy can present with neurological and psychiatric symptoms, and it is important to be aware of possible underlying medical etiologies of seemingly psychiatric presentations. In this case, cancer-associated limbic encephalitis presented with classical signs of catatonia, progressive cognitive decline and psychotic depression. Methods: A 68-year-old Caucasian female with past medical history of COPD, ongoing heavy tobacco use, and depression presented with rapidly worsening cognitive function over a nine months. Her cognitive symptoms were accompanied by psychotic features and delusions of ruin that her body and hair were burnt. Her medications on presentation included sertraline, trazodone, quetiapine and clonazepam. Physical examination was remarkable for classical signs of catatonia including catalepsy, gegenhalten, staring, perseveration, echolalia, echopraxia, hypophonia, and automatic obedience. MOCA scores were 19/30. Medical work-up undertaken for rapidly progressive dementia included a paraneoplastic antibody panel due to concerns of paraneoplastic limbic encephalitis. Anti-Hu antibodies were positive and further investigation revealed Stage IIIA small cell lung cancer. The patient was started on venlafaxine and mirtazapine for depression, olanzapine for psychosis and for paraneoplastic syndrome she was referred for treatment of underlying cancer and received a short course of steroids, which improved her cognitive function remarkably. Lorazepam helped improve catatonic symptoms. Results: The early detection of small cell lung cancer in limited stage (IIIA) resulted from the paraneoplastic work up prior to onset of physical symptoms and increased the possibility of curative treatment with radiation therapy and chemotherapy. Conclusions: The early detection of small cell lung cancer in limited stage (IIIA) resulted from the paraneoplastic work up prior to onset of physical symptoms and increased the possibility of curative treatment with radiation therapy and chemotherapy. Paraneoplastic syndromes should be considered on the differential for rapid cognitive decline, psychosis and personality changes especially when there is increased suspicion for malignancy.