SAN FRANCISCO — Clinicians detected underlying rheumatic disease in 17 of 28 patients referred to a multidisciplinary clinic for interstitial lung disease.
The evaluations changed the diagnosis in 11 of the 28 patients, including 4 of 15 who had been referred for idiopathic interstitial lung disease and 7 of 13 who had been referred for rheumatic disease related to interstitial lung disease. As a result, clinicians changed therapy for 14 (50%) of the patients, Dr. Flavia V. Castelino and her associates reported at the annual meeting of the American College of Rheumatology.
All patients with interstitial lung disease should be evaluated by a rheumatologist, said Dr. Castelino of Massachusetts General Hospital, Boston.
Distinguishing between interstitial lung disease that is idiopathic versus related to rheumatic disease is important because the former carries a worse prognosis, and the response to treatment may differ, Dr. Castelino said.
A separate retrospective study of 362 cases of interstitial lung disease found 5-year survival rates of approximately 40% with idiopathic disease and approximately 70% with cases that were associated with rheumatic disease (Am. J. Resp. Crit. Care Med. 2007;175:705–11).
The difference in prognosis is thought to be related to the major lung histopathology, previous data suggest. Nonspecific interstitial pneumonia was present in 4 (9%) of 47 patients with idiopathic interstitial lung disease and in 23 (83%) of 28 patients with undifferentiated connective tissue disease and interstitial lung disease in one study (Am. J. Resp. Crit. Care Med. 2007;176:691–7).
A separate previous study of 39 cases of interstitial lung disease found that community physicians were more likely to diagnose it as idiopathic disease, compared with retrospective diagnoses from a multidisciplinary academic team review by pulmonologists, radiologists, and pathologists (Am. J. Resp. Crit. Care Med. 2007;175:1054–60).
In the current prospective study of patients referred by pulmonologists over an 8-month period to a new multidisciplinary clinic at Brigham and Women's Hospital, Boston, all patients were evaluated by a pulmonologist and a rheumatologist, who took a complete history and physical examination (including capillary microscopy) and reviewed laboratory and serologic data. They reviewed available imaging and pathologic specimens in consultation with a dedicated radiologist and a pathologist experienced in interstitial lung disease.
Additional serologic tests, imaging, or biopsies were performed at the discretion of the clinic physicians. They initiated or changed therapy in collaboration with the referring physician.
Evaluations by a rheumatologist significantly affected diagnoses because of additional serologic testing (such as a myositis panel) and because the rheumatologist was able to elicit subtle clues that are suggestive of a rheumatologic diagnosis. Recognition of “mechanic's hands,” periungual erythema, abnormal capillary microscopy, and inflammatory arthritis led to new diagnoses including antisynthetase syndrome, systemic sclerosis, rheumatoid arthritis-associated interstitial lung disease, mixed connective tissue disease, dermatomyositis, and undifferentiated connective tissue disease.
The cohort was half female, with a median age of 63 years and a history of smoking in 23 patients (82%).
The investigators reported having no potential conflicts of interest related to this study.
All patients with interstitial lung disease should be evaluated by a rheumatologist. DR. CASTELINO
Clinicians detected underlying rheumatic disease in 61% of patients who were referred for interstitial lung disease. ©American College of Rheumatology Clinical Slide Collection 1972–2004