Doctors in Seattle believe a woman was infected with rare, brain-eating amoebas after she used tap water in netipot to rinse her sinuses.

The unidentified 69-year old woman died in February, but her case was just now reported in the latest edition of the International Journal of Infectious Diseases.  She had a lingering sinus infection and used the neti pot, a teapot-like vessel, to irrigate her nasal passages.  But instead of following most manufacture's guidelines and using saline solution or sterile water she used tap water.

Unfortunately, the tap water contained the parasite Balamuthia mandrillaris - an amoeba that's pretty harmless if ingested, but in the nasal passages can cause a very rare and almost always fatal infection in the brain.  The women's problems developed slowly.  The first symptom was a red rash on her nose - doctors prescribed an anti-bacterial lotion, but it didn't work.  Over the course of a year, dermatologists hunted for a diagnosis.

Late, she suffered a seizure and her left side went weak.  Scans revealed lesions on her brain, but doctors didn't realize the extent of the damage until they opened her skull.

"When I operated on this lady, a section of her brain about the size of a golf ball was bloody mush," said neurosurgeon Dr. Charles Cobbs from Seattle's Swedish Hospital in an interview with The Seattle Times.  "There were these amoeba all over the place just eating brain cells.  We didn't have any clue what was going on, but when we got the actual tissue we could see it was the amoeba."

They contacted The US Centers for Disease Control and Prevention which rushed the anti-amoeba drug miltefosine to Seattle to try to save the woman's life.  However, she fell into a coma and died.

The CDC says most cases of Balamuthia mandrillaris aren't diagnosed until immediately before death or after death, and because it's so rare doctors just don't have enough experience with it.