Atypical presentation of anti-Ma2-associated encephalitis mimicking diencephalic demyelinating syndrome

Anti Ma 2 encephalitis is an autoimmune encephalitis, usually paraneoplastic, characterized by isolated or combined limbic, diencephalic, or brainstem dysfunction. It most commonly affects males with testicular or small cell lung cancer, though cases have been reported in females with gynecologic malignancies [1]. We describe an unusual presentation of a paraneoplastic neurologic syndrome presenting with predominant involvement of the hypothalamus and deep grey nuclei secondary to a testicular cancer associated with anti-Ma2 antibody.