BrainRecommendations to Distinguish Behavioural Variant Frontotemporal Dementia from Psychiatric Disorders

Read the original article

Behavioral variant frontotemporal dementia (bvFTD) presents significant diagnostic challenges due to its symptomatic overlap with primary psychiatric disorders (PPD). This comprehensive review by the Neuropsychiatric International Consortium for Frontotemporal Dementia provides evidence-based recommendations for distinguishing bvFTD from psychiatric conditions, addressing a critical diagnostic gap that often leads to delays in proper treatment.

Key Points:

• Approximately 50% of bvFTD patients receive an initial psychiatric diagnosis, with diagnostic delays averaging 5-6 years from symptom onset. Conversely, patients with PPD are sometimes misdiagnosed with bvFTD.
• The consortium recommends including at least one formal social cognition test in standard neuropsychological batteries, emphasizing the importance of 3D-T1 brain MRI with standardized review protocols and validated visual atrophy rating scales.
• CSF or serum neurofilament light chain (NfL) shows promise as a biomarker for distinguishing bvFTD from PPD, with studies showing high diagnostic accuracy (AUC 0.93 for CSF NfL).
• FDG-PET is useful for excluding bvFTD when results are normal, but clinicians should avoid over-interpreting non-specific regional metabolism abnormalities when considering psychiatric diagnoses.
• The consortium recommends C9orf72 genetic screening for all possible/probable bvFTD cases or suspected cases with strong psychiatric features, even without family history.

HCN Medical Memo
The systematic approach outlined in these consensus recommendations emphasizes the importance of comprehensive assessment, including social cognition testing, standardized neuroimaging protocols, and genetic screening, to improve the differential diagnosis between bvFTD and psychiatric disorders.

More on Alzheimer’s/Dementia