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 patients 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.
The results emphasize that all patients with interstitial lung disease should be evaluated by a rheumatologist, concluded 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, she 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, previously published studies suggest.
For example, 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, recently published study of 39 cases of interstitial lung disease found that community physicians were more likely to diagnose the condition as idiopathic disease, compared with retrospective diagnoses from a multidisciplinary academic team review conducted by a group of 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.
The physicians also 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 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 also undifferentiated connective tissue disease.
The patient cohort was half female, with a median age of 63 years and a history of smoking in 23 (82%) of patients.
The multidisciplinary interstitial lung disease clinic now meets weekly and has evaluated an additional 28 patients.
In this group, diagnoses were changed in eight patients, including five patients referred for idiopathic disease who were ultimately found to have rheumatic disease-related interstitial lung disease, Dr. Castelino commented.
The investigators reported having no potential conflicts of interest related to this study.
Rheumatologists' recognition of rheumatic lung disease changed therapy in 50% of cases. DR. CASTELINO