Bacteria Causes 'Hot Tub Lung'

Patients who suffer from cough and breathlessness may be victims of what doctors call hot tub lung, Minnesota researchers report at the American Thoracic Society international meeting.

"Doctors often don't think to ask their patients if they have been using a hot tub," says Viktor Hanak, MD, pulmonary fellow at the Mayo Clinic in Rochester, Minn. "Patients also need to tell their doctors if they regularly use a hot tub if they have respiratory problems."

The study alerts physicians and the general public to the phenomenon of hot tub lung; it is a series of cases so there is no information on how common this is, says J. Randall Curtis, MD, international program chairman for the American Thoracic Society.

"But this is a treatable condition and it's important to receive early treatment before damage is done," Randall tells WebMD.

Hot Tubs May Damage Lungs

The Mayo report includes 22 people who had symptoms for an average of seven months. All had coughing, shortness of breath, fever, and weight loss, says Hanak.

The patients were on average 46 years old and included both men and women.

"They had fatigue and their oxygen levels dropped to dangerous levels so they had to be put on oxygen. It took months before they were diagnosed," he says.

Although most had been to the doctor, they were misdiagnosed with asthma or bronchitis, he tells WebMD. "It is difficult to diagnose if you don't think of asking about a hot tub, but nobody thinks of it. Therefore, most patients have been diagnosed with something else."
They were eventually diagnosed with hot tub lung after doctors looked at X-rays and found a particular bacterium in lung secretions, lung tissue, or hot tub water. The bacterium, called Mycobacterium avium, can get into the lungs and cause infection from the bubbling hot water and the mist that it creates.

Main Culprit: Poorly Maintained Hot Tubs

The infection is more likely to occur if the hot tub isn't properly maintained.

Hanak says the condition occurs when individuals don't change the water and the filter in the hot tub frequently enough and don't shower before getting in the tub.

"While the disease isn't transmittable, the whole family can get it by sitting in the hot tub. People need to be really careful with hot tub maintenance," he says.

According to the CDC, water temperatures above 84 degrees make chlorine lose most of its disinfectant properties.

The problem often is compounded when the patients get ill, are extremely tired, and are coughing, he says. "They get back in the hot tub thinking the mist will help their cough. This only makes the problem worse. This is even more likely to happen if the hot tub is inside."

In the early stages, all you have to do is tell patients to drain the hot tub and stay away from it, Hanak advises. However, some patients must be placed on anti-inflammatory steroids and antibiotics.

With this treatment nearly 44 percent of the patients had their symptoms clear up during a follow-up of almost 10 months; the others had improvement, he notes. "Sometimes this takes about a year to completely clear up."

Sources: American Thoracic Society 2005 International Conference, San Diego, May 20-25, 2005. Vitrik Hanak, MD, pulmonary fellow, Mayo Clinic, Rochester, Minn. J. Randall Curtis, MD, international program chairman, ATS.

By Linda Little
Reviewed by Brunilda Nazario, MD
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