Alzheimer's Disease and Chlamydia Pneumoniae

By William K. Summers, MD
© William K. Summers, MD

It is common wisdom that Alzheimer's disease is genetic. ß-amyloid peptide, a chemical component of the senile plaques, is one of the genetic theories of Alzheimer's disease. An alternative theory has been that Alzheimer's disease is caused by tau protein. Tau is a chemical component of the neurofibrillary tangles seen in microscopic views of Alzheimer's patients' brains. The bottom line of both theories is that "bad genes" cause Alzheimer's. The Federal Government has invested hundreds of millions of dollars trying to prove these theories.

But does it take sixty years to figure out if we got a bad set of genes? Frankly, this theory never did make sense to me. It was politically correct. Are not parents supposed to be the cause of their children's problems? So what if it takes more than sixty years to blame our parents for flawed genes?

But lo. At the most recent meeting of The Society Of Neuroscience in Los Angeles, a startling paper appeared. It was a modest poster among 12,000 posters. The poster appeared on the fifth day of the meeting. In fewer than 500 words, a group of scientists from Johns Hopkins and Hahnemann Schools of Medicine changed the field of Alzheimer's disease. They demonstrated that Alzheimer's could be due to an infection by Chlamydia pneumoniae, ... bacteria. How politically insensitive! Imagine that we "caught" our Alzheimer's from friends or even strangers! It turns out that bacteria called Helicobacter cause most stomach and duodenal ulcers.

It was a careful study. Chlamydia pneumoniae is a small bacteria. It is usually isolated from the throat, nose and sinuses. Chlamydia can manage to live inside the cells of its host human for years. As such it is very resistant to most antibiotics. Chlamydia has been implicated as the cause of "culture negative" earaches, sore throats, and sinusitis. In the past five years Chlamydia has been considered as the cause of emphysema, auto-immune diseases such as sarcoidosis, and even coronary artery disease. It seems that Chlamydia also likes to live in fatty plaques lining arteries.

This study was exquisite. It first showed fragments of Chlamydia DNA in the brains of 17 of 19 Alzheimer's brains. Analysis of 19 age-matched control brains did not show fragments of Chlamydia DNA in 18 cases. Next the scientist stained the brains of Alzheimer's brains with very special stains that tag only Chlamydia antibodies. When they looked under the microscope, they found the Chlamydia. The staining was concentrated in the same areas of the brain most severely affected by the ravages of Alzheimer's disease! Next they looked with the electron microscope at the Alzheimer's patients' damaged nerve cells. With this powerful microscope, they found Chlamydia structures inside nerve cells (vegetative form) and surrounding nerve cells (infectious form). They found the bacteria in the middle of the tau and ß-amyloid. Finally, the scientists did the specialized culture necessary to grow Chlamydia on fresh brain material. They actually grew Chlamydia from the two Alzheimer's samples. They failed to grow the bacteria from the two control brains.

The evidence for Chlamydia being involved is pretty convincing. However, did it cause the damage of Alzheimer's? OR did the damage of Alzheimer's allow the Chlamydia to come into the brain?

The NM Senior Citizen News publishes these articles monthly. You can pick up a copy of the paper at your closest New Mexico Senior Citizen Center.