New specialist at University of Chicago Medicine works to clear things up on lesser-known disease
By Tom Mullaney
Dr. Pamela McShane has been on staff as a pulmonary and critical care physician at the University of Chicago Medicine (UCM) only since January 2011, but she already has made important discoveries about an uncommon and often misdiagnosed disease: bronchiectasis. Her study on ethnicity as a causative factor, published in the July issue of the journal, Chest, yielded new discoveries.
Bronchiectasis refers to the widening of airways inside the lungs, preventing the proper discharge of mucus. As a result, the airways become inflamed and infected, causing constant coughing and shortness of breath. Patients suffer a repeated loop cycle of inflammation, infection and significant lung damage over time.
This affliction can develop at any age, but symptoms may not appear until much later in life. Fewer than 1 in 20,000 persons aged 18–34 have the disease, but that proportion rises exponentially to 1 in 100 after age 60. A disproportionate two-thirds of the affected population are white women over 60.
Damage caused by bronchiectasis is irreversible but can be slowed down and held in check. “This is a cumulative process,” says McShane, “so early diagnosis can make a huge difference. The sooner we can intervene, the better we can control the process.” Unfortunately, most physicians now label the symptoms as asthma or chronic bronchitis.
One of McShane’s earliest patients was Rebecca Haskin. Haskin had been to see 10 doctors prior to coming to McShane. She had been unable to receive a conclusive diagnosis. Earlier physicians’ diagnoses were either asthma or an allergy.
Haskin is unable to work due to her severely reduced lung capacity, but McShane’s diagnosis made a big difference. “It now all makes sense. I’m now a part of the PCD (Primary Cilia Dyskinesia) community and connected to other people (like herself).” She calls McShane “the most caring doctor I’ve ever had.”
Haskin showed her gratitude for her PCD diagnosis by raising $10,000 to enable the UCM pulmonologist to buy an expensive hi-tech machine for her research—a nasal nitric oxide analyzer. As a result, she can now perform advance analyses, not being done previously, on bronchiectasis.
McShane is one of few physicians in the Chicago area specializing in the disease, and physicians nationwide refer patients to her. Such referrals and patients she treated during her three-year fellowship at the UCM have enabled her to assemble a large registry of bronchietasis patients and to study its causes on multiple fronts.
Her recently published research presented full evaluations of 106 patients. Earlier studies were conducted with homogeneous populations that assigned a probable cause to fewer than half of all cases. McShane and her two co-authors, UCM’s Dr. Edward T. Naureckas and Dr. Mary E. Strek believed that a more diverse population would highlight significant differences by ethnicity and etiology.
They were able to determine an immune deficiency or an autoimmune process in a vast majority of the cases. Yet, the findings on ethnicity’s role were more eye-opening. Rheumatoid arthritis was found as the cause of bronchiectasis in 28.6 percent of the African-American patients in the study versus only 6.2 percent of European-American patients in the study. In 20 percent of subjects the cause of bronchiectasis was related to pre-existing hematologic malignancy or stem cell transplantation. Interestingly, the majority of these patients were European-American, and none were African-American.
Additionally, a significantly higher percentage of Hispanic-American patients had pseudomonas (a type of bacterium) in their sputum (mucus coughed up from the lower airways) compared with the African-American and European-American patients. Pseudomonas has been shown to correlate with worse disease and a more rapid decline in lung function than other types of bacteria
Building on her Chest study research, McShane says she now wants to focus future research on advanced PCD study, and study other organisms, particularly fungus in sputum, seeking a direct correlation to bronchiectasis.
As a result of her study and talks she has given, McShane says the UCM is now seen as “a real center for bronchiectasis.”
Tom Mullaney is a freelance journalist whose articles have appeared in Chicago Tribune, TheNew York Times and Chicago magazine. This is Mullaney’s first article for Chicago Health.[email_link]