For years, recurring bouts of pneumonia and bronchitis suggested that further testing might be needed. Instead, Pat Moore, 61, of Johnson was continually diagnosed with asthma. In January 2004, the Master Gardener and active swimmer, racquetball player and hiker was scheduled for back surgery. At the time, she was experiencing chronic coughing, exhaustion and difficulty breathing when walking uphill. Her presurgery X-ray landed in the hands of Dr. Murray Harris, an investigative radiologist in Fayetteville, who noticed a spot on her right lung. Several other doctors told Moore they probably would have overlooked it, Moore said.
Tests showed that the spot was growing. Concerned that it might be cancerous, Moore had two lobes from her lung removed in February 2004. Samples were sent to the lab, and it took about two months to pinpoint a diagnosis.
At first, it was thought to be tuberculosis, Moore said. But more testing indicated pulmonary mycobacterium avium complex, or MAC, an infection of the lungs that is being diagnosed with increasing frequency.
Dr. Steven Holland, an infectious disease specialist with the National Institutes of Health in Bethesda, Md., heads a MAC research group. He estimates the NIH treats about 100 MAC patients each year.
The disease is difficult to diagnose because its symptoms are vague and not dramatic, Holland said. Many doctors are unfamiliar with it, and it often slips by undetected on X-rays.
"If the major symptom of this illness is cough and fatigue in a 60-year-old woman, well, many 60-year-old women have a cough and are fatigued," he said. "Many doctors say, ' You're getting older and you've got a cold. ' Until they come back enough times for somebody to say this is outside the realm of normal, most people don't think to do more testing."
Holland is uncertain whether the disease is becoming more prevalent. However, an increasing number of cases are being identified.
"This is the generic problem of rare diseases: You really don't know if they're rare because nobody has identified them or they're rare because they're rare," Holland said. "Have I seen more in 2006 than in 1996 ? Absolutely. But I also work harder to see it."
A mysterious germ Two of the more familiar types of mycobacteria, M. tuberculosis and M. leprae, have caused much human suffering through tuberculosis and leprosy. Both diseases are transmitted from person to person. Moore's illness is caused by two kinds of mycobacteria found in soil, air and water - even chemically treated municipal supplies - and acquired from the environment, not other people. We are exposed every day. So why don't more people come down with infections ? One of the mysteries of MAC is that a very specific demographic appears to be susceptible. "It's largely a disease in this country of older Caucasian women," Holland said, adding that there is also an association with tall, thin body shapes. "We're still working very hard to figure it out," he said. Other risk factors include lowered immune systems, as in AIDS patients, and chronic lung conditions such as cystic fibrosis and bronchiectasis. According to information at www. maclungdisease. org, MAC also appears to be more prevalent in those with scoliosis, gastroesophageal reflux disease, asthma and chronic bronchitis.
Moore has bronchiectasis in both lungs. The condition involves chronic dilation of breathing tubes that causes secondary infection, usually in the lower portion of the lungs. It is considered incurable and results in excessive mucus production, inadequate airways, coughing and susceptibility to other infections.
Several cases of MAC have originated with indoor hot tubs and enclosed shower stalls. In an April article in The Salem (Mass. ) News, Dr. Michael Iseman of the National Jewish Medical and Research Center in Denver explained a possible reason.
Forty years ago, people set their hot water heaters to 160 degrees. That dropped to about 125 degrees during a 1970 s energy crisis. About the same time, the American Academy of Pediatrics recommended the lower temperature to prevent children from scalding themselves. While 160-degree water would kill any mycobacteria living in pipes, germs can thrive at 125. Another possible factor, Iseman said, is the increasing popularity of showers over baths. In an enclosed shower stall, people inhale warm, moist air that may contain the bacteria. Moore doesn't know how she acquired MAC. She has always been active outdoors and in her gardens, and she also once lived on a farm with a contaminated well. While the disease can be fatal if left untreated, it is usually more debilitating than life-threatening, Holland said. "It certainly produces lots of symptoms that can take the pleasure out of being an otherwise vital 70-year-old," he said. Diagnosis and treatment
Unless a test for
MAC is specifically
requested, it will not be done, Holland said. However, the organism is easy to identify if it's being looked for. Patients most often experience chronic cough, fatigue, night sweats, fever and loss of weight or appetite. However, many of those symptoms are vague and can result from a host of illnesses, Holland cautioned.
His recommendation is to discuss a chest X-ray or a MAC culture with a doctor if one experiences uncharacteristic fatigue with a chronic cough and sputum production.
Treatment currently consists of three antibiotics - clarithromycin, ethambutol and rifampin - taken by mouth or sometimes intravenously for one to one and a half years. The therapy can be difficult for patients. Moore's treatment lasted 18 months, during which she lost 60 pounds and experienced tremendous weakness and fatigue.
"The drugs are sometimes not very well-tolerated," Holland said. "Like all antibiotic therapy, they can cause diarrhea, vaginitis, nausea - they can make life unpleasant."
A bigger problem is that once treatment is complete, the relapse rate is significant, probably about 30 to 50 percent, Holland estimated. Research is ongoing for better treatments.
Moore knows a Rogers woman with MAC who has had six relapses. Moore has frequent checkups, and in June, doctors found another spot on her lung. They told her it could be inflammation from a recent illness, but they want to keep an eye on it.
Even if Moore does not relapse, the bronchiectasis damage to her lungs is permanent. She will be susceptible to lung and breathing problems for the rest of her life. Her current regimen consists of nasal sprays and an Acapella device, which helps clear her lungs of mucus to prevent it from growing or becoming infected. Seeking support
When Moore was
diagnosed, she
had never heard of MAC. She felt isolated and alone, unable to find much information about her condition, she said. So she contacted the Centers for Disease Control in Atlanta.
Through the CDC, she learned of Iseman and attended a conference for MAC patients at the National Jewish Medical Center in May where Holland was a speaker. She also contacted the NIH and is participating in one of its research trials.
She now wants to get the word out about MAC and start a monthly support group for patients in Northwest Arkansas.
"I may be able to help," Moore said. "People might think, gee, that sounds like something I might have."
For more information on MAC, visit www. ntminfo. com or www. maclungdis ease. org. To join Moore's support group, contact her at 751-9327.
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