001 An unusual cause of lymphocytic meningitis

A 36-year-old Spanish man, with a background of ketamine use, presented with a 10-day history of severe headache, photophobia, nausea, unsteadiness and slurring of speech. His CT head was normal. CSF white cell count was 151 (lymphocytes), protein 0.7, glucose 2.3 (serum 3.6). He was treated with IV acyclovir for two weeks with no clinical improvement.On examination he remained distressed by headache and photophobic with severe dysarthria, bidirec- tional nystagmus and ataxia.Blood tests were normal or negative including HIV, serology for syphilis, mycoplasma, lyme and brucella, ANA, ENA, dsDNA, ANCA, ACE, LGI1 and NMDA antibodies, anti-Hu, Ri and Yo. IGRA was positive. MRI brain scan was normal. Serial lumbar punctures showed a variable CSF white cell count, with a negative extended virology panel, TB PCR, bacterial cultures, cytology and immunophenotyping.There was no improvement with pulsed steroids or antimicrobial cover for listeria. After 5 plasma exchanges there was some improvement in his CSF white cell count and headache, but he remained very ataxic.An extended paraneoplastic panel revealed positive anti-Tr antibodies. This is a well recognised cause of paraneoplastic cerebellar degeneration, normally associated with Hodgkin’s lymphoma. There have been no previous reported cases of anti-Tr antibodies associated with meningitic symptoms.