Aqua Lung: Indoor Hot Tubs Found to be Source of Lung Disease, National Jewish Physician Reports at American Thoracic Society Conference

DENVER-Microscopic organisms contained in aerosols generated by indoor hot tubs can cause lung disease in the people who regularly use them, a National Jewish Medical and Research Center physician reports today at the American Thoracic Society (ATS) International Conference.

National Jewish physicians recently treated nine people, including four children, for a lung disease caused by nontuberculous mycobacteria (NTM). NTM—specifically Mycobacteria avium and fortuitum—were found in the hot tub water and/or in the air of the homes of the people diagnosed. The hot tubs are located inside of homes, near family and living rooms, and bedrooms.

"The jets from hot tubs aerosolize the bacteria, which is how this becomes a problem," said Cecile Rose, MD, MPH, a National Jewish physician specializing in treating people with environment and occupational lung diseases, and reporting the research findings at ATS. "Bubbles—rich with the bacteria—rise up, burst and disperse the bacteria throughout a room."

Unlike its bacterial cousin tuberculosis—transmitted by infected humans—NTM is not contagious. In nature, these organisms live in brackish ocean water, like tide pools. But indoor hot tubs, which generally produce a substantial mist, may be causing this lung disease to become more prevalent. The organisms enter the air when a mist, called aerosolization, is produced and the bacteria are suspended in water droplets.

People with NTM often suffer from fever, tiredness, night sweats, cough and weight loss. "For people with mild cases of NTM, removing the hot tub from the home is the primary treatment," she said.

In more severe cases, and those reported on at the ATS conference, treatment involved corticosteroids and/or corticosteroids and antimycobacterial antibiotics. Sometimes three to four antibiotics must be given at once.

This respiratory problem is often misdiagnosed as sarcoidosis—characterized by inflamed, microscopic growths called granulomas most often found in the lungs—or tuberculosis. "This disease mimics other granulomatous lung diseases, but few people understand the link between hot tub exposure and the symptoms of disease," she said. In instances when the lung problems are misdiagnosed, and in three cases reported at the ATS conference they were, patients remained in the home, prolonging their exposure to NTM.

Nevertheless, Dr. Rose adds, "Because luxury items like hot tubs are becoming more common, I believe there will be an increasing recognition and understanding of the risk associated with their use among doctors and consumers."