Detecting Connective Tissue Disease-Associated Interstitial Lung Disease: What Are Current Screening Strategies?

Dr Kimberly Showalter

Interstitial lung disease (ILD) is a leading cause of morbidity and mortality among individuals with systemic sclerosis (SSc)^[1] and also negatively affects survival for those with other connective tissue diseases (CTD), including rheumatoid arthritis (RA),^[2] Sjogren’s syndrome,^[3] and myositis.^[4] Symptoms of ILD include cough and shortness of breath; however, some patients, even those with a high burden of radiographic ILD changes, may have few or no symptoms.^[5]

Dr Jessica Gordon

Further, it is increasingly recognized that early identification and treatment is key to improving outcomes for individuals with CTD-ILD. Indeed, currently approved treatments have been shown to prevent ILD progression rather than yield large improvements in pulmonary function. Therefore, it is essential for rheumatologists and other treating physicians to recognize known risk factors associated with ILD development and progression and to screen at-risk patients with appropriate testing.

Incidence, Risk Factors, and Screening for CTD-ILD

Systemic Sclerosis.Depending on the modality of detection used, ILD may be present in >80% of individuals with SSc. Risk factors for progressive SSc-ILD include male sex; African American race; diffuse subtype; anti-Scl-70 autoantibody positivity; nucleolar ANA; elevated C-reactive protein; baseline forced vital capacity (FVC) <70% of predicted; baseline diffusing capacity of carbon monoxide (DLCO) <55% of predicted; and greater extent of fibrosis on high-resolution computed tomography (HRCT) (>20%).