Mysterious brain diseases in Canada weren't a mystery after all

Six years ago, a Canadian neurologist claimed to notice strange symptoms in a cluster of patients in New Brunswick, a province bordering Maine.

Six years ago, a Canadian neurologist claimed to notice strange symptoms in a cluster of patients in New Brunswick, a province bordering Maine.  

According to the neurologist, Dr. Alier Marrero, the patients suffered hallucinations, spasms, rapid memory loss and the sensation that bugs were crawling underneath their skin, but their symptoms and brain scans didn’t neatly fit an existing diagnosis. In other words, the cases were a mystery.    

But since then, neurologists who have reviewed the cases have identified clear diagnoses, including Alzheimer’s, Parkinson’s and cancer.

A study published this week in JAMA Neurology reinforces those findings, putting the probability of a mystery disease at roughly 1 in a million.  

Doctors working on the study evaluated 25 people who had been identified as part of the New Brunswick cluster. Eleven of the patients had died, so neuropathologists used autopsies to determine their illnesses. For the 14 living patients, neurologists relied on cognitive assessments, among other tests. They concluded that all of the patients had well-known conditions such as Alzheimer’s, Parkinson’s, cancer, traumatic brain injuries or post-concussion symptoms.