De gedragsvariant van frontotemporale dementie

Introduction: Diagnosing behavioral variant frontotemporal dementia (bvFTD) is challenging because of its broad differential diagnosis and the clinical resemblance with the symptoms of psychiatric illnesses like bipolar disorder, schizophrenia, depression, obsessive compulsive disorder, kleptomania and personality disorder. The new FTD consortium criteria (2011) emphasize the importance of distinguishing possible and probable bvFTD. A significant number of possible bvFTD patients remain with normal neuroimaging results and without functional decline at long term follow up: the bvFTD phenocopy syndrome. A neurodegenerative nature of this condition is unlikely although an alternative explanation is missing. Case description: Patient D was a 52 year old man who was initially diagnosed with bvFTD according to the former Neary et al. FTD consensus criteria (1998). Clinical follow up of 3 years raised doubt on this diagnosis because of repeated neuroimaging results and the absence of functional decline. We describe the multidisciplinary diagnostic process including neurological examinations, neuropsychological examinations and psychiatric observation on a clinical ward. His neuropsychiatric syndrome could be explained by a combination of a below-average intelligence, cluster C personality traits and relational problems and the diagnosis of bvFTD was withdrawn. Conclusion: Acknowledging possible bvFTD as a clinical syndrome that might not be caused by neurodegenerative FTD can reduce the number of false positive diagnoses and is important to maintain quality in medicine. Using this new criteria a flow chart is proposed to improve diagnostic process.