Anti-N-methyl-D-aspartate-receptor encephalitis as a harbinger of pediatric HIV infection

Anti-N-methyl-D-aspartate-receptor (A-NMDAR) encephalitis is the most common type of autoimmune encephalitis in the pediatric age group. It is known to be triggered by viral infections such as herpes simplex infections. However, A-NMDAR encephalitis with HIV infection is a very rare event, with cases reported mostly in adults. The current report is of a previously healthy child who presented with recurrent vomiting, irritability, visual impairment, and new onset complex partial seizures and right somatosensory seizures with generalization occurring in clusters. Over a period of 3 weeks, he developed rapidly progressive bilateral painless visual loss, visual hallucinations, and behavioral changes. Brain magnetic resonance imaging (MRI) showed predominantly cortical symmetrical T2/FLAIR hyperintense signal change in parieto-occipito-temporal regions. The serum and cerebrospinal fluid were strongly positive for anti-NMDAR antibodies, and he also tested positive for HIV-1 antibodies acquired by vertical transmission. The patient and mother tested positive for HIV antibodies for the first time. Repeat MRI revealed gliosis in the parieto-occipito-temporal regions, and hippocampi showed volume loss and T2/FLAIR hyperintense signal change in the posterior thalami with patchy hyperintensities in the right putamen. The seizures subsided with immunomodulation along with anti-epileptic drugs, but he had residual cortical visual impairment on follow-up. This is the first report of A-NMDAR encephalitis presenting as a harbinger of HIV infection in a child. This calls for testing for A-NMDAR antibodies in children with HIV infection presenting with neurological or neuropsychiatric manifestations.