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Introduction Cerebrospinal fluid (CSF) dementia biomarkers are recommended in situations of diagnostic uncertainty. Interpretation is nuanced and haphazard testing may produce incidental positive results without preceding clinical syndrome. Improving dementia diagnosis is imperative given recent developments of promising disease-modifying treatments and serum biomarkers.Methods CSF dementia biomarker requests received at King’s College Hospital, London were collected between April 2023 – March 2024. Medical records were reviewed for indications and results of total-tau (t-tau), phosphorylated-tau (p-tau), amyloid-B 42 (AB42), amyloid-B 40 (AB40), neurofilament light chain (NFL) and S100.Results A total of 51 requests were received (two samples were repeat testing). T-tau, AB42, AB40 were requested across the majority of samples, whereas NFL and S100 were requested infrequently. No p-tau requests were received.28 requests were deemed inappropriate requests, of which nine requests were in the context of normal pressure hydrocephalus; the remaining samples included subarachnoid haemorrhage, encephalitis and incidental imaging findings. 19 samples were positive for amyloid-B 42/40 ratio, with the majority (13) being requested in the context of cognitive decline by cognitive specialists.Conclusion CSF dementia biomarkers requests outside of dementia specialists can often be inappropriate, costly and uninformative, highlighting the potential need for specialist triaging. Standardisation of panel requesting should also be implemented.haoxuanhli@outlook.com