The contaminated water went up the woman's nose "toward [the] olfactory nerves in the upper part of her nasal cavity", The Seattle Times reported, which ultimately caused the infection which first appeared as a red sore on her nose.
"When I operated on this lady, a section of her brain about the size of a golf ball was bloody mush", Charles Cobbs, a neurosurgeon at Swedish Medical Center, told the Seattle Times. "We didn't have any clue what was going on, but when we got the actual tissue we could see it was the amoeba". These sorts of infections are quite rare, but what's unique about this incident is that it's the "first case of Balamuthia mandrillaris brain infection suspected from nasal lavage", according to the case study, which was authored by Swedish scientists and the doctors who worked on the case, Cobbs included. That said, the woman's case was rare; there were only three similar cases in the USA from 2008 to 2017, according to the Center for Disease Control and Prevention (CDC).
After using the prescribed neti pot for a month, she developed a rash near her nose, which was misdiagnosed as rosacea. This single-celled organism is not to be confused with Naegleria fowleri, another brain-eating amoeba that also lives in freshwater. After experiencing an intense seizure and an apparent loss of brain cognition, doctors started to investigate the possibility of the problem being in her brain. "There were these amoeba all over the place just eating brain cells". When doctors took a CT scan of her brain, they found what they initially believed to be a large tumour.
The amoeba was discovered in 1986. Since then, more than 200 cases have been diagnosed worldwide, with at least 70 cases in the US, the CDC says.
As in the Seattle woman's case, the infections are "almost uniformly fatal", with a death rate of more than 89%, according to the doctors who treated her and the CDC. A rare amoeba (called Balamuthia mandrillaris) was feasting on her brain, according to a recent study published in the International Journal of Infectious Diseases (IJID). "At this point, the family made a decision to withdraw support".
Health officials say Neti pots can be safe to use as long as you follow the instructions and fill them only with boiled or distilled water.
"Improper nasal irrigation has been reported as a method of infection for the comparably insidious amoeba", the doctors say in the research paper about the Seattle woman.