Many people rely on continuous positive airway pressure (CPAP) machines as a safe and effective treatment for sleep apnea. But a new case report describes a rare complication—a lingering inflammatory disease of the lungs, apparently related to the use of contaminated well water in a CPAP machine. The report appears in the December Southern Medical Journal, official journal of the Southern Medical Association. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health, a leading provider of information and business intelligence for students, professionals, and institutions in medicine, nursing, allied health, and pharmacy.
Dr. Lawrence W. Raymond and colleagues of Carolinas HealthCare System, Charlotte, describe an unusual case of lung disease related to CPAP, which uses humidified air to keep the airways open while the patient is sleeping. The patient in the case report had used her CPAP machine for several years with no problems—she was careful about cleaning her machine and filling it with distilled water, as recommended.
Symptoms Developed After Using Well Water for CPAP
The problem started when the patient forgot to bring a supply of distilled water on a trip to her North Carolina vacation home. Instead, she used tap water, which came from a well located a few miles away. She awoke the next morning with a severe sore throat, and immediately suspected that her symptoms were caused by using tap water in her CPAP machine.
The patient was ill for several weeks—with "crackles" in the lungs and decreased blood oxygen levels—despite treatment with antibiotics. She finally started getting better after beginning treatment with steroids; her condition gradually improved over several weeks. However, even three years later, she still had minor problems related to a chronic cough.
An infection from contaminated well water was suspected, but testing of the water showed no bacteria. Instead, there were high levels of a toxic bacterial compound called endotoxin, probably related to repair work done on the pipes a few weeks earlier.