LIVERPOOL, ENGLAND – Very few patients with idiopathic pulmonary fibrosis have connective tissue disease antibodies, suggesting that IPF is a “robust diagnosis” when made on the basis of standard diagnostic tests, it was reported at the British Society for Rheumatology annual conference.
“The results were perhaps not what we’d expected,” said Caroline V. Cotton, PhD, of the Institute of Ageing and Chronic Disease at the University of Liverpool, England.
This means that chest physicians are getting the diagnosis right in the majority of cases, based on currently available methods, such as patients’ clinical history and examination, the results of high resolution–computed tomography, and widely available serology. “Which is good news,” Dr. Cotton observed.
Interstitial lung disease (ILD) comprises a huge spectrum of disorders. The main groups of ILDs are idiopathic, granulomatous, connective tissue disease–associated environmental, or medication exposure–associated; and the rare causes of ILD, each of which contain multiple subgroups of which IPF is one.
Sometimes it is obvious to respiratory physicians what the cause is, such as environmental exposure to asbestos or sarcoidosis for the granulomatous ILD, Dr. Cotton noted. Identifying connective tissue disease (CTD)–associated ILD can be more diagnostically challenging, however, and there are a large number of rheumatic conditions associated with CTD-associated ILD, including rheumatoid arthritis, systemic sclerosis, and Sjögren’s syndrome, to name a few.
One of the problems is that signs and symptoms of CTD may be absent at the time ILD starts to manifest and, even if signs are present, they may too subtle to be picked up in a general chest clinic. There also is a large number of antibodies for CTDs, but not all are widely available.