Trouble may be bubbling in the soothing waters of your hot tub.
A new respiratory condition, commonly called hot tub lung, has surfaced in the past few years. It is not clear how prevalent it is, but it is enough of a concern that last fall, Mayo Clinic researchers urged doctors to routinely ask about hot tub use when diagnosing respiratory ailments.
The culprit is nontuberculosis mycobacteria, one of several bugs that can thrive in hot tub water. The steam and bubbles aerosolize the organism, making it easy to breath in.
All reported cases of hot tub lung have been attributed to indoor hot tubs, where the bacteria-laden mist is less likely to disperse. Most have involved tubs in homes.
There are about 5-million hot tubs in the United States, according to the National Spa and Pool Institute. It is not known how many are indoors, though clearly the minority are.
Mark and Margie Maloney had never heard of hot-tub lung when they decided to add a room onto their Monument, Colo., home for their hot tub. They brought the tub with them from New Jersey, where it had been outside.
The Maloneys installed the hot tub in August and soaked in it just about every day. There are several windows in the hot tub room, but they kept them closed to keep out the cold. "A bad, bad mistake," Mark Maloney said.
Within a month, his wife had fallen ill.
"It was like a flulike thing where I was totally exhausted," said Margie Maloney, 65, who also was bothered by a persistent cough.
She saw a series of doctors: her regular physician, an ear, nose and throat specialist, a cardiologist and finally, in January, a pulmonologist. The pulmonologist suspected hypersensitivity pneumonitis, which involves an inflammation of the lungs, but couldn't say what caused it.
"No one thought to ask me if I had a hot tub," Margie Maloney said.
But once the Maloneys came across an article on hot tub lung and showed it to the doctor, he advised her to avoid the tub.
The most effective treatment is to eliminate exposure to the hot tub, said Dr. Cecile Rose of National Jewish Medical and Research Center in Denver, which has been at the forefront in investigating hot tub lung, studying about 30 cases. Many undiagnosed patients unwittingly worsen their condition by continuing to use their hot tub, hoping that a good soak will make them feel better, Rose said.
Some patients go on steroid therapy. Although some patients have been treated with antibiotics, the condition appears to be an immune reaction rather than an infection, Rose said.
Many patients return to normal, but patients may be left with lung impairment, Rose said.
Margie Maloney is taking prednisone, which acts as an immunosuppressant and an anti-inflammatory. She is also on oxygen and doesn't know when that will end. For a time, doctors feared that her lungs had been scarred, but that wasn't the case.
Mark Maloney doesn't know why he didn't get sick, too. As a runner, perhaps his lungs are stronger than his wife's, he said.
It is not clear whether proper maintenance and tub cleaning are enough to keep the tub safe. The Mayo researchers said that chlorine loses much of its strength as a disinfectant at temperatures higher than 84 degrees.
In some cases Rose has investigated, people were "very fastidious" about cleaning the tub.
The Maloneys plan to get rid of their hot tub, which sits empty.
"We made some major decisions in our lives sitting in the hot tub and kicking things around," Mark Maloney said. "I'm going to miss it."