To describe the real-world temporal trends, positivity rates and spectrum of neural antibody findings using panel-based evaluations from a single tertiary academic center in Singapore.

Autoimmune encephalitis and paraneoplastic neurological disorders are increasingly recognized as treatable causes of neurological disease. However, data on the utilization and diagnostic yield of comprehensive neural antibody panels in real-world Southeast Asian populations remain limited. Understanding testing trends provides insight into clinician awareness, case selection and evolving disease recognition. 

This is a retrospective review of all patients at National University Hospital, Singapore, who underwent neural antibody evaluations  between 1 January 2018 and 8 August 2024 for clinical purposes. Aquporin-4 and MOG antibody assays were excluded. The samples were analyzed at the Mayo Clinic Neuroimmunology Laboratory. The number of tests, positivity rates and antibody types were examined for both serum and cerebrospinal fluid (CSF) across paraneoplastic and autoimmune encephalopathy panels.  

A total of 1413 patients underwent neural antibody testing during the study period. Paraneoplastic panels included 113 serum and 77 CSF samples, while autoimmune encephalopathy panels included 533 serum and 483 CSF samples. Overall, 170 positive results were identified; after excluding low positive GAD antibody results, 100 positive results remained. The most frequent antibodies were NMDAR (n=34); VGCC (n=14); LGI1 (n=7) GABABR (n=7), and GFAP (n=7) antibodies.  Other antibodies detected (<5 each) included ANNA-1, CASPR2, Ganglionic receptor acetylcholine, AMPAR, Glycine, mGluR1, PCA-1, PCA-2, AP3B2, striational antibodies. Over time, testing volume increased, reflecting growing clinical recognition of autoimmune neurology.  

This eight-year experience demonstrates that comprehensive neural antibody panels, which are not readily available in Southeast Asia and include antibodies not covered by most commercial test, have enabled a much wider spectrum of autoimmune and paraneoplastic neurological disorders. Their use has expanded diagnostic accuracy and awareness of autoimmune neurology.