Failure to correlate C. pneumoniae with late onset Alzheimer's disease.

Chlamydia pneumoniae is a common cause of community acquired respiratory infections such as pharyngitis, bronchitis, and pneumonia. The detection of C. pneumoniae in 17 of 19 brain samples from patients diagnosed with AD using PCR, RT-PCR, culture, electron microscopic and immunohistochemical analysis recently has been reported.1 We conducted a pilot study to confirm these observations. Brain samples, from AD cases (n = 9, including parahippocampal gyrus, entorhinal cortex, and temporal cortex) and non-AD cases (n = 2, temporal cortex and hippocampus) were examined as a blind panel using PCR and immunohistochemistry. Immunohistochemistry (figure) was performed on impression slides taken from the frozen brain samples using a C. pneumoniae –specific monoclonal antibody (DAKO). Nested PCR procedures were performed using sets of primers specific for C. pneumoniae , namely the 76-kd protein gene1 and the …