1: Med Hypotheses. 2006;67(3):592-600. Epub 2006 May 3.

Plaques of Alzheimer's disease originate from cysts of Borrelia burgdorferi, 
the Lyme disease spirochete.

MacDonald AB.
St. Catherine of Siena Medical Center, Department of Pathology, 50 Rte 25 A, 
Smithtown, NY 11787, USA. [email protected]

Here is hypothesized a truly revolutionary notion that rounded cystic forms of 
Borrelia burgdorferi are the root cause of the rounded structures called 
plaques in the Alzheimer brain. Rounded "plaques' in high density in brain 
tissue are emblematic of Alzheimer's disease (AD). Plaques may be 
conceptualized as rounded "pock mark-like" areas of brain tissue injury. In 
this century, in brain tissue of AD, plaques are Amyloid Plaques according to 
the most up to date textbooks. In the last century, however, Dr. Alois 
Alzheimer did not require amyloid as the pathogenesis for either the disease or 
for the origin of its plaques. Surely, amyloid is an event in AD, but it may 
not be the primal cause of AD. Indeed in plaques, amyloid is regularly 
represented by the "congophilic core" structure which is so named because the 
waxy amyloid material binds the congo red stain and is congophilic. However an 
accepted subset of plaques in AD is devoid of a congophilic amyloid core region
 (these plaques "cotton wool" type plaques, lack a central congophilic core 
structure). Furthermore, there is "plaque diversity" in Alzheimer's; small, 
medium and large plaques parallel variable cystic diameters for Borrelia 
burgdorferi. Perturbations of AD plaque structure (i.e. young plaques devoid of 
a central core and older plaques with or without a central core structure) 
offer room for an alternate pathway for explanation of ontogeny of the plaque 
structures. If amyloid is not required to initiate all of the possible plaques 
in Alzheimer's, is it possible that amyloid just a by product of a more 
fundamental primal path to dementia? If a byproduct status is assigned to 
amyloid in the realm of plaque formation, then is amyloid also an epiphenomenon 
rather than a primary pathogenesis for Alzheimer's disease. In the "anatomy is 
destiny" model, cysts of borrelia are always round. Why then not accept 
roundness as a fundamental "structure determines function" argument for
 the answer to the mystery of why Alzheimer plaques are always round? Parataxis 
causality, a concept borrowed from philosophy, is the error that comes from 
linking two events, which occur contemporaneously or in close proximity to one 
another with a cause and effect relationship. Parataxis tells us that what 
appears to be cause and effect in the couplet "amyloid plaque" merely by a 
proximity relationship may be "spurious causality" which is a cognitive dead 
end.

PMID: 16675154 [PubMed - indexed for MEDLINE]