A recent North American study detected Chlamydia pneumoniae in 17 of 19 bra
ins of Alzheimer's patients and supposed a C. pneumoniae infection to be a
risk factor for Alzheimer's disease (AD). In this study, we analyzed paraff
in-embedded tissue samples of 20 AD patients by nested PCR and immunocytoch
emistry with a panel of antichlamydial antibodies and could detect neither
C. pneumoniae-specific DNA nor chlamydial antigens; From our data, the pres
ence of C. pneumoniae in the brains of Alzheimer's patients is not a common
phenomenon; an association remains questionable.