To investigate the clinical and neuroimaging features of autoimmune encephalitis (AIE) and paraneoplastic neurologic syndromes (PNSs) associated with various neuronal-specific antibodies.

AIE and PNSs are immune-mediated disorders that can potentially affect any region of the nervous system, leading to diverse neurologic manifestations. PNSs are associated with cancer, demonstrating oncologic heterogeneity, whereas AIE might not be linked to malignancy. Research has discovered several neuronal autoantibodies with these conditions; however, their radiological features have not been well-characterized.

A literature review of studies published between 2014 and 2023 was conducted using PubMed, EMBASE, and Google Scholar. Of the 379 articles screened, 65 were analyzed, detailing demographic and clinical features, oncological diagnosis, antibody type, neuroimaging findings, treatment, and outcomes of patients with AIE or PNS.

Among 333 patients with AIE (n=245) and PNSs (n=88), the mean age was 54, with a 2:1 male-to-female ratio. Common tumors included seminomas and lung, ovarian, and breast malignancies. Presentations encompassed cognitive impairment, limbic encephalitis, cerebellar syndrome, rhomboencephalitis, chorea, and myelopathies. Neuro-radiological findings revealed distinct associations between antibody type and lesion location. Medial temporal lobe hyper-intensities were the most common (29.4%), associated with anti-LG1 and anti-NMDAR antibodies. Similarly, cerebellar (24.4%) and brainstem (15%) involvement was seen with anti-KLHL11 and anti-LUZP4 antibodies, hippocampal involvement (12.1%) with anti-GABABR, spinal cord hyperintensities (10.6%) with anti-LUZP4, and basal ganglia involvement (2.6%) with anti-PDE10A and anti-CV2/CRMP5 antibodies. High-risk antibodies (>70% associated with cancer) were predominant in males, affected deep brain structures, and showed increased mortality. Low/intermediate-risk antibodies (<70% associated with cancer) were predominant in females, involving cortical areas, with a better prognosis.