Possible N -methyl- D -aspartate receptor antibody-mediated encephalitis in the setting of HIV cerebrospinal fluid escape

Discordant elevations of cerebrospinal fluid (CSF) human immunodeficiency virus (HIV) ribonucleic acid (RNA) in chronically treated patients known as ‘CSF escape’ may present as acute encephalitis. Infectious encephalitis caused by herpes simplex virus (HSV) and other neurotropic viruses have been identified as potential triggers of anti- N- methyl- D -aspartate receptor (NMDAR) encephalitis. Autoantibody-mediated encephalitis has been infrequently reported in HIV infected patients and may mimic HIV encephalitis. We report two adults infected with HIV presenting with encephalopathy and seizures. Case 1 had a monophasic encephalopathy with detection of NMDAR antibodies in the context of HIV CSF escape. There was a clinical response to immunotherapy and anti-retroviral therapy adjustment. Case 2 initially presented in non-convulsive status epilepticus associated with HIV CSF escape. He responded to treatment with anti-epileptic drugs and anti-retroviral therapy alteration, but had two further neurological relapses. NMDAR antibodies were detected during the relapses and a clinical response was observed following treatment with immunotherapy. Clinicians should consider autoimmune encephalitis in HIV infected patients presenting with encephalopathy and seizures, particularly in cases with concomitant HIV CSF escape.