Gomez-Ramos_1993_Med.Clin_101_60

For the pathological diagnosis of Alzheimer's disease ADRA-NIH recommend the quantification of plaques, without distinguishing their types, and neurofibrillary tangles. However, diffuse plaques may not be specifically associated to such diagnosis, as suggested by several authors and a previous paper. The neurofibrillary degeneration, present not only in neurofibrillary tangles but also in neuropil threads, either free in the neuropil or associated in plaques, could be more closely correlated with the decrease of cognitive functions than the plaques by themselves. In the present work, the efficiency of cholinesterase histochemical techniques and thioflavin-S is compared to the immunocytochemistry for abnormal tau, in two aspects: 1) the quantification of neurofibrillary degeneration, 2) the distribution of this degeneration, when present, within the plaques. It is concluded that immunocytochemistry for tau is the technique that better fulfills both goals, showing a better agreement with the cognitive state. For that reason tau immunocytochemistry is highly recommended in order to improve the anatomopathological diagnosis of Alzheimer's disease.