Abstract

A 75-year-old female was referred to the neurology outpatients department with a 6 month history of progressive amnesia and cognitive decline as well as symptoms/signs suggestive of a sensory neuropathy. Past medical history included TIA, cervical spondylosis and recent investigation for hyponatraemia which had been attributed to SIADH. She had been a smoker with a 50+pack year history and consumed minimal alcohol. An MRI brain scan demonstrated bilateral hippocampal T2 hyperintensity. A lumbar puncture demonstrated normal CSF constituents and negative viral PCRs. Full autoimmune and paraneoplastic screening was undertaken which was all normal except for a positive anti-Hu antibody. A CT-TAP highlighted a mass lesion in the right middle lobe of the lung and biopsy confirmed small cell lung cancer (T1aN2M0). A diagnosis of anti-Hu antibody related paraneoplastic syndrome was made and an initial treatment course of IV Methylprednisolone was administered. The patient’s cancer was treated with chemotherapy and adjuvant radiotherapy. Despite a good response with regard to her tumour and hyponatraemia, the patient did not improve significantly cognitively. This case highlights the need for awareness of the combination of symptoms/signs of the described ‘anti-Hu syndrome’ with paraneoplastic sensory neuropathy and/or encephalomyelitis.