British Columbia

Brain-eating amoeba linked to nasal rinse for Seattle woman

It was a brain surgery like no other for Dr. Charles Cobbs.

Doctors thought the patient had a brain tumour, turned out it was a rare amoeba

Improper use of a neti pot is being linked to a Seattle woman's brain-eating infection (Shutterstock )

It was a brain surgery like no other for Dr. Charles Cobbs.

"It's something I've actually never seen before ... pathologists couldn't really determine what it was because the tissue had been pretty much destroyed," said Cobbs, a neurosurgeon at Seattle's Swedish Medical Center.

Cobbs was operating on the patient last January for what he thought was a brain tumour. When he opened her up, the damage was so severe he sent a portion of it away for testing.

It turned out a rare amoeba had been eating her alive.

Cobbs believes it was the patient's use of a neti pot, a tea-pot shaped product used to relieve sinuses by shooting water up the nasal cavity, that put the amoeba into her brain. He says she used tap water, as opposed to the suggested boiled water or saline.

Rare infection

The patient had a rare brain infection called Balamuthia mandrillaris. It's a free-living amoeba found in soil and fresh water and generally causes no harm to humans.

Dr. Cobbs wrote about the case for a recent edition of the International Journal of Infectious Diseases. 

The publication doesn't identify the patient.

The report says the rare amoeba was discovered in 1986 in an autopsy from the brain of a mandrill monkey at San Diego Zoo and was declared a new species in 1993.

It also says there have only been about 200 cases of human infection recorded worldwide, and at least 70 in the U.S. The fatality rate for Balamuthia infection is near 100 per cent.

"If you directly ... injected (it) into your nasal passageways, if there's enough of it, it could, you know, set up an infection," explained Cobbs.

"I suspect it was in her nasal passages and skin in the nose, and, after a while, enough of it was around that it got into the bloodstream and probably went to the brain."

According to the paper, the infection first showed up as a skin lesion on the woman's nose. Doctors treated it for about a year, as if it were the common skin condition, rosacea.

Cobbs says the rarity of the amoeba made her condition difficult to quickly diagnose. Eventually, the patient had a stroke, then doctors did a CT scan. At that point, they diagnosed her with a brain tumour.

It wasn't until she underwent surgery that they diagnosed the infection. In spite of removing the portions damaged by the amoeba, the patient died within a month of diagnosis. 

Nasal rinse warning

Cobbs encourages those who use a nasal rinse to wash containers properly. 

"I suspect it was probably a container that had been sitting around ... an amoeba could set up shop in there and then the tap water had been maybe sitting around and maybe it just grew in that," he said.

He says neti pots are a good way for those with sinus issues or the flu to get relief, if used properly.


To encourage thoughtful and respectful conversations, first and last names will appear with each submission to CBC/Radio-Canada's online communities (except in children and youth-oriented communities). Pseudonyms will no longer be permitted.

By submitting a comment, you accept that CBC has the right to reproduce and publish that comment in whole or in part, in any manner CBC chooses. Please note that CBC does not endorse the opinions expressed in comments. Comments on this story are moderated according to our Submission Guidelines. Comments are welcome while open. We reserve the right to close comments at any time.

Become a CBC Member

Join the conversation  Create account

Already have an account?