Guidelines for the neuropathologic diagnosis of Alzheimer’s disease and dementia with Lewy bodies
Although Alzheimer’s disease (DA) was described by Alois Alzheimer at the beginning of this century, it was during the 1980s that the neuropathological criteria for improved diagnosis were established. In 1985 Khachaturian et al established a system based on the quantity of senile neuritic plaques (SNP) per field according to the patient’s age. In 1991 the Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) confirmed the importance of categories associated with age, introduced the concept of the importance of the presence of neurofibrillary tangles (NT) for diagnosis of AD and established that in ‘definite’ AD there should also be clinical correlation with dementia. In the same year Braak and Braak presented a pattern of NT formation and a staging system. In 1997, based on consensus between researchers in the USA and Europe, under the auspices of the National Institute on Aging and the Reagan Institute, the use of the criteria of CERAD was recommended, and the importance of the presence of NT for greater diagnostic certainty was emphasized; it was also suggested that the criteria of Braak and Braak should be used. The disorder known as dementia with Lewy bodies (LB) is relatively new. In some of these patients the dementia syndrome is only associated with Lewy bodies , whilst in others (the majority) LB coexists with AD. It is thought that 15-30% of the patients with AD may have LB. In 1996 the first diagnostic guidelines were drawn-up for DLB (Consensus Guidelines for the Clinical and Pathological Diagnosis of Dementia with Lewy Bodies). The usefulness of these criteria has yet to be proved by research at different centres. It is quite possible that these criteria will require modification in the future as the disorder becomes better understood
