Selective neurofibrillary degeneration of the hippocampal CA2 sector is associated with four-repeat tauopathies

Takashi Ishizawa, Li Wen Ko, Natalie Cookson, Peter Davies, Marisol Espinoza, Dennis W. Dickson

Research output: Contribution to journalArticle

47 Scopus citations


The CA2 sector of the hippocampus is relatively resistant to neurofibrillary tangles in aging and Alzheimer disease; however, some cases have selective neurofibrillary degeneration in CA2 with sparing of the more vulnerable CA1 sector. Cases such as this do not fit in the Braak and Braak staging scheme and can be considered to have an atypical pattern of neurofibrillary degeneration. We identified 24 atypical cases with an average age at death of 78.6 ± 1.4 yr and ayerage Braak stage of 3.2 ± 0.4 and describe their pathologic and genetic characteristics with Gallyas silver staining, immunohistochemistry for tau and αΒ-crystallin, as well as apolipoprotein-E (ApoE) and tau genotyping; Three cases were excluded from further analysis due to presence of hippocampal sclerosis. All but 1 of the remaining 21 atypical cases were four-repeat (4R) tauopathies, including progressive supranuclear palsy, corticobasal degeneration, and argyrophilic grain disease (AGD). Remarkably, 19 of the 21 atypical cases were pure or mixed cases of AGD. The ApoE ε4 allele frequency was similar to normal controls, while there was a trend for an increased frequency of the extended tau HI haplotype in atypical cases. Selective neurofibrillary degeneration in CA2 sector of the hippocampus is not widely recognized, but when detected should suggest the possibility of a 4R-tauopathy, particularly AGD.

Original languageEnglish (US)
Pages (from-to)1040-1047
Number of pages8
JournalJournal of Neuropathology and Experimental Neurology
Issue number12
StatePublished - Dec 1 2002


  • Argyrophilic grain disease
  • CA2
  • Hippocampus
  • Neurofibfillary tangles
  • Tau

ASJC Scopus subject areas

  • Pathology and Forensic Medicine
  • Neurology
  • Clinical Neurology
  • Cellular and Molecular Neuroscience

Fingerprint Dive into the research topics of 'Selective neurofibrillary degeneration of the hippocampal CA2 sector is associated with four-repeat tauopathies'. Together they form a unique fingerprint.

  • Cite this