The possibility that Alzheimer’s disease (AD) has a microbial aetiology has been proposed by several researchers. Now, Spanish scientists have provided evidence that tissue from the central nervous system (CNS) of deceased AD patients contains fungal cells and hyphae. Different brain regions including the external frontal cortex, cerebellar hemisphere, entorhinal cortex/hippocampus and choroid plexus contain fungal material which is absent in brain tissue from controls.
Analysis of brain sections from 10 additional AD patients revealed that all are infected with fungi. Fungal infection was 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 identified several fungal species.