Introduction:

Neuropsychiatric syndromes frequently present as the initial manifestation of autoimmune encephalitis, complicating differentiation from primary psychiatric disorders.

Objective:

To determine the spectrum of neuropsychiatric syndromes that may present as primary manifestations in autoimmune encephalitis, which contribute to the differential diagnosis and clinical management of these patients.

Method:

A systematic review of recent literature was conducted, including reviews, cohorts, case series and guidelines, extracting clinical, paraclinical and therapeutic data.

Results:

Distinct serological phenotypes emerge: anti-NMDAR with florid psychiatric onset, catatonia and autonomic dysfunction; anti-LGI1 with limbic phenotype and anterograde amnesia. Biomarkers (FLCK, OCB) and CSF/serum CBA enhance detection; EEG/MRI may be normal early. Early immunotherapy (steroids, IVIG, PLEX) improves outcomes; ECT and second-line agents are effective for refractory cases.

Conclusions:

a presumptive diagnosis, targeted testing and early immunomodulatory treatment are recommended.