What are the obstacles for an accurate clinical diagnosis of Pick's disease? A clinicopathologic study

Publisher Website
Google Scholar
Abstract
Several studies have evaluated the reliability and validity of the clinical diagnosis of Alzheimer9s disease (AD) using well-defined neuropathologic criteria, but none has attempted to evaluate the diagnostic accuracy of Pick9s disease. We determined the accuracy of the clinical diagnosis of Pick9s by presenting 105 autopsy-confirmed cases of Pick9s (n = 7) and related disorders (non-Pick9s, n = 98) as clinical vignettes in randomized order to six neurologists who were unaware of the autopsy findings. The group of raters had moderate to fair agreement for the diagnosis of Pick9s as measured by the κ statistics. The sensitivity for the diagnosis of Pick9s for the first visit (mean, 53 months after onset) and last visit (mean, 78 months after onset) was low (range, 0 to 71%), but specificity was near-perfect. Median positive predictive values at both visits were 83 to 85%. False-negative misdiagnoses mainly involved AD. False-positive diagnoses were rare and occurred with corticobasal degeneration (first visit) and with dementia with Lewy bodies (last visit). Pick9s was also misdiagnosed by primary neurologists. The best clinical predictors for the early diagnosis of Pick9s included "frontal" dementia, early "cortical" dementia with severe frontal lobe disturbances, absence of apraxia, and absence of gait disturbance at onset. However, the first neurologic evaluation in some of the Pick9s cases took place in advanced stages of the disease. Our findings suggest that this disorder is underdiagnosed in clinical practice. Although the low sensitivity for the clinical diagnosis of Pick9s is disappointing, our data suggest that when clinicians suspect Pick9s, their diagnosis is almost always correct. Absence of awareness of the main features of this disorder and of specificity of the frontal lobe syndrome may partially explain the low detection of Pick9s disease.

This publication has 22 references indexed in Scilit: