A hard-to-treat lung infection is on the rise and the culprit could be right in your own home.
Nancy O’Connor had a cough that she couldn't shake.
“I was coughing constantly," she says. "The kids would just say that’s just Mrs. O’Connor, she coughs all the time.”
The 67-year-old says she was frustrated because doctors couldn’t nail down the cause.
She says, “I’ve had two bronchial scopes and CAT scans and X-rays. I mean, almost too many to tell you.”
Then finally a surprising diagnosis. Nancy had an infection in her lungs from non-tuberculosis mycobacteria or NTM.
“He said that it came from shower vapors," she said. "And I’m thinking, shower vapors?”
The NTM organism grows in soil and is carried by water.
Dr. John Hansen-Flaschen says, "An attractive, current theory is that people breathe a fine mist in their shower stalls of municipal water containing small amounts of this bacteria.”
The infection shows up on an X-ray as patches of pneumonia.
Dr. Hansen-Flaschen says, "We’re imagining that’s where the original seed of a water droplet landed and took hold.”
In the past, doctors saw the disease only in cigarette smokers and miners who inhaled silica.
Dr. Michael Iseman says, "It is now a disease largely of women. And not only that, but predominantly among Caucasian women.”
And they’re mostly non-smokers, like Nancy. She had to take daily doses of three antibiotics for two years to get rid of the infection.
Dr. Hansen-Flaschen says, "The reason it’s so hard to treat is that the bacteria is generally highly resistant to the antibiotics that we have available today.”
Water above 170 degrees can kill the bacteria but you can't shower in water that hot without getting burned. So how do you prevent the infection?
Dr. Hansen-Flaschen says, "One possibility, if the research confirms our theories, would be to have our home water heaters heat the incoming water to 170 degrees for two to three minutes, then cool it down to 125 degrees in a holding bin so that what comes out of the pipe can’t be more than 125 degrees or so.”
For now, you can switch to baths or try a showerhead with a rain-like spray instead of a mist. More importantly, if you have a stubborn cough with phlegm and feel zapped of your energy, see a doctor.
Nancy O’Connor says, "If you’ve got something like that, that’s just a cough or cold that just keeps lingering on, it doesn’t hurt to have it checked out.”
Though rare, symptoms of infection with NTM include fever, weight loss, cough, lack of appetite, night sweats, bloody sputum and loss of energy. The NTM bacteria are cousins to the bacteria that cause TB and leprosy.
Fast Facts:Approximately two out of every 10,000 Americans develop an infection with a non-tuberculosis mycobacterium.
Cases appear to be on the rise, especially in women over age 50.
The bacteria can be found in water and researchers theorize that some people acquire the infection by inhaling fine, contaminated water droplets from the shower.
Non-tuberculosis Mycobacterium Infection
A non-tuberculosis mycobacterium (NTM) infection is a disease caused by a bacterium in the same family as that which causes tuberculosis (TB) and leprosy. Like TB, the infection tends to mainly affect the lungs. Patients may experience chronic cough, fever, weight loss, night sweats, fatigue, loss of appetite and blood-tinged phlegm.
According to the National Jewish Medical and Research Center, each year, about two in every 10,000 Americans develop an NTM infection. A common cause is a bacterium called Mycobacterium avium, leading to Mycobacterium avium complex, or MAC.
It can be difficult for doctors to diagnose NTM. The infection is somewhat rare and patients may be initially misdiagnosed. Some only have an annoying cough that never seems to go away. Others may develop signs of pneumonia and will be treated for that condition. When symptoms continue to persist, doctors may order an X-ray. If the X-ray is suspicious, a CT chest scan may be ordered. NTM has very characteristic patterns on the chest CT scan. A culture of the sputum can confirm the presence of the NTM bacteria.
Once the diagnosis is made, treatments can be started. John Hansen-Flaschen, M.D., a Pulmonary and Critical Care Medicine Specialist at the University of Pennsylvania Hospital, says the bacteria are often resistant to at least one antibiotic. So patients are usually placed on multiple antibiotics. Even with treatment, the bacteria are very difficult to eliminate. So patients may be on antibiotics for as long as a year or two. In some patients, if the infection is confined to a small area of the lung, surgeons may remove that portion of the lung.
Women, Showers and NTM
Doctors are seeing an increase in the number of cases of NTM infection, especially in older women (typically over 50). The bacteria are commonly found in water and soil. Some investigators have been able to find the bacteria in showerheads and on the walls of shower stalls. Michael Iseman, M.D., a Pulmonologist with National Jewish Medical and Research Center, says researchers theorize women acquire the bacteria by inhaling contaminated droplets in the mist of shower water. Not everyone gets the infection. So doctors aren’t sure why older women appear to be more at risk for the disease.
NTM is not contagious from person to person. But it can be very difficult to eradicate. The bacteria can live for a long time on surfaces and in the water and soil. It is resistant to common germicides and is tolerant to heat. Hansen-Flaschen says heating the water for two to three minutes at more than 170 degrees will kill the bacteria. But water at that temperature would cause serious burns. Switching to baths (instead of showers) may reduce the risk of infection. For those who prefer showers, an alternative may be a low impact showerhead that doesn’t produce a fine mist or spray.
Web ResourcesCenters for Disease Control and Prevention Web site
For information about non-tuberculosis mycobacterium and mycobacterium avium complex:
National Jewish Medical and Research Center Web site
Stop NTM Now Web site