Table 2.

Morphologic variations of p-tau.

Neurofibrillary Tangle
Ghost (extracellular) tangle
Pretangle
Dystrophic neurite
Neuropil thread
Grain
Pick body
Tufted astrocyte
Equivocal tufted astrocyte
Coiled body
Astrocytic plaque
Globular glial inclusion
Ramified astrocyte
Thorny astrocyte
Bushy astrocyte
Fuzzy astrocyte

There are numerous and expanding microscopic lesions that label with antibodies to p-tau, most of which are not disease-specific. A subset is relatively specific (e.g., tufted astrocytes—progressive supranuclear palsy, astrocytic plaques—corticobasal degeneration, Pick body—Pick disease), although interobserver variability has not been explored, and neurodegeneration per se (loss of neurons, atrophy) is a better correlate of clinical signs.