Anti-NMDAR encephalitis following malaria: expanding the spectrum of post-malarial neurological syndromes.

Background: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most common form of autoimmune encephalitis (AIE), often triggered by viral infections or tumors. This report describes a rare case following a parasitic infection. Case findings: We report a rare case of anti-NMDAR encephalitis developing in a 40-year-old man following recovery from Plasmodium falciparum malaria. Despite confirmed parasite clearance, he presented eleven days later with seizures, altered consciousness, and acute psychosis. Anti-NMDAR antibodies were detected in the cerebrospinal fluid (CSF) via both immunofluorescence and cell-based assay, with no evidence of concurrent infection or malignancy. The patient showed rapid clinical improvement after first-line immunotherapy. Conclusion: This report represents the first antibody-confirmed case of anti-NMDAR encephalitis following Plasmodium falciparum infection, highlighting malaria as a novel post-infectious trigger and expanding the recognized spectrum of post-malarial neurological syndromes (PMNS). It underscores that clinicians in endemic regions should maintain a high index of suspicion for AIE in patients with new neuropsychiatric symptoms after malaria and pursue early antibody testing and immunotherapy.