3145 Indications, diagnostic yield and management impact of paraneoplastic and autoimmune encephalitis antibody testing

test the validity of this framework in a real-world PCA population.Methods We completed a retrospective audit of Eastern Cognitive Disorders Clinic (ECDC) patients with a clinician-determined final diagnosis of PCA (N=32) 2008-2022: age at diagnosis, time to diagnosis and the clinical, cognitive, and neuro-imaging features.We compared our patients' presentations with the core cognitive features included in the framework and their presence at first assessment. ResultsThirty (93.8%)ECDC clinician diagnosed PCA patients fulfilled the criteria: cognitive features correlated well with the framework for the top four features (visuo-spatial and -perceptual deficits, simultanagnosia, constructional apraxia).100% of patients had MRI brain, but only 38% were reported as PCA; 84% had FDG-PET brain with 59% reported as PCA.Most (28, 87.5%) presentations were in keeping with a PCA-pure syndrome.Three patients met criteria for PCA-plus-CBS and one for PCA-plus-DLB.Average delay to diagnosis was 4 years with mean symptom onset at age 59 years.Conclusion Our patients' cognitive features closely aligned with the consensus framework, corroborating its real-world applicability.Neuroradiological reporting was identified as a key challenge.This represents new Australian data on PCA syndromic diagnosis.