A new study has been released where researchers from Madrid, Spain, believe they show, at the very least, a clear correlation and
possibly a causation between Alzheimer's disease and a brain fungus caused by infection.
The possibility that Alzheimer’s disease (AD) has a microbial aetiology has been proposed by several researchers. Here, we provide evidence that tissue from the central nervous system (CNS) of AD patients contain fungal cells and hyphae. Fungal material can be detected both intra- and extracellularly using specific antibodies against several fungi. Different brain regions including external frontal cortex, cerebellar hemisphere, entorhinal cortex/hippocampus and choroid plexus contain fungal material, which is absent in brain tissue from control individuals. Analysis of brain sections from ten additional AD patients reveals that all are infected with fungi. Fungal infection is also observed in blood vessels, which may explain the vascular pathology frequently detected in AD patients. Sequencing of fungal DNA extracted from frozen CNS samples identifies several fungal species. Collectively, our findings provide compelling evidence for the existence of fungal infection in the CNS from AD patients, but not in control individuals.
The findings are very promising, if only for the possibilities of treating or solving at least some part of the Alzheimer's mystery. And while any find in the field of Alzheimer's and dementia-related illness is exciting, we must temper our excitement with scientific practicality and fact.
The Economist puts together a sobering response to the study's news.
If fungal infection did turn out to be responsible for Alzheimer’s, that would be excellent news. Medicine already possesses plenty of anti-fungal medications that could be raided to produce anti-Alzheimer’s drugs. But Dr Carrasco’s evidence, while intriguing, is far from conclusive. John Hardy, a neuroscientist at University College, London, points out that one (albeit rare) cause of Alzheimer’s is well-understood. In a few unlucky families the disease appears to be an inherited disorder, caused by mutations of one of three genes. If a fungal infection were the ultimate cause, then those genetic mutations would have to make their carriers so susceptible that 100% of them end up infected, something he believes is unlikely. And the very clarity of Dr Carrasco’s result also makes Dr Hardy suspicious.
That being said, the genetic link could be one of susceptibility to this kind of brain infection. This may just be one small aspect of the disease that millions suffer from and millions more will suffer from. But, any and all research of this nature can yield important results for some and in this case, maybe many, people.