Commentary on the consensus recommendations for the post mortem diagnosis of Alzheimer's disease

The consensus recommendations for the post mortem diagnosis Alzheimer's disease (AD) highlight the difficulties in establishing a pathological diagnosis in brains from clinically demented individuals with both certainty and uniformity. There is, however, a need for diagnostic guidelines that are relatively simple, inexpensive, and adaptable to general pathologists and different laboratories. The current Consortium to Establish a Registry for Alzheimer's disease (CERAD) criteria and the recommendations in the consensus document giving three probabilistic categories for diagnosis go a long way towards establishing a uniform approach for the diagnosis of AD. However, more uniformity could be adopted in the topography of sectioning to enhance diagnostic and future research comparisons. We also recommend that immunohistochemistry for βA4 (Aβ) amyloid and tau-reactive neurofibrillary changes, in addition to hematoxylin and eosin stains, should become the basis for histological diagnosis. We agree with the guidelines concerning documentation of all AD changes. Until a clearer understanding of the early changes of AD is established, strict observation and recording are the pathologists' best diagnostic skills. The ill-defined diagnostic areas of AD continue to prompt the need for a new method of detection of the underlying pathologic process.