Examples of risk factors include anti-SCL-70 antibody and elevated acute phase reactants in systemic sclerosis; high titer RF or anti-CCP in rheumatoid arthritis; anti Jo-1 or ulcerating lesions in idiopathic inflammatory myopathies; or dysphagia or Raynaud’s phenomenon in mixed connective tissue disease. (A more complete list of risk factors will be included in the full manuscript.)
Because this patient had both systemic sclerosis and factors increasing her risk, Dr. Khanna explained that she definitely needed screening, even though she did not have signs or symptoms of ILD, such as cough.
The guideline conditionally suggests that patients who have a relevant SARD but no other factors increasing their risk of ILD may not need such screening unless they have potential signs or symptoms; however, clinicians should still bring up the option with their patients.
Per the guideline, Dr. Khanna noted that screening for higher risk patients should consist of both pulmonary function testing—including spirometry, lung volumes and diffusion capacity—and high-resolution chest CT. Pulmonary function testing alone is not sufficient, as it can miss 15–20% of patients with early ILD, explained Dr. Khanna.
Dr. Johnson noted that CT angiogram, which may be administered to a patient with acute shortness of breath in an emergency setting, is often inadequate to screen for ILD.
The guideline also includes conditional recommendations against screening with the six-minute-walk test, chest radiography, ambulatory desaturation testing or bronchoscopy, with a strong recommendation against screening with surgical lung biopsy. However, using these tests may be helpful in specific circumstances.
Short-term glucocorticoids are conditionally recommended as part of treatment for other types of SARDs, but for systemic sclerosis, the strong recommendation is against their use. This is due to risks of triggering renal crisis in this condition & lack of data demonstrating their efficacy in treating systemic sclerosis-related ILD.
Clinical Case Continued
The patient’s pulmonary function tests showed a mild restriction in forced vital capacity confirmed with a decreased total lung capacity and a proportional decline in diffusion capacity, a finding that would be uncommon in lung disease of other etiology, such as pulmonary vascular disease. The high-resolution chest CT showed ground glass opacities and a few interstitial markings, with very early but definite ILD.
Clinical Question: Should this patient be treated? What is the best approach?
Dr. Khanna shared that this patient should definitely be treated, given these findings and her other high-risk factors. However, he added the guideline doesn’t imply that every patient with ILD necessarily needs immediate treatment. For example, a rheumatologist may use a different approach in a patient with a forced vital capacity of 100%.
