American Board of Internal Medicine (ABIM) Certification Practice Exam

What is a recommended treatment for interstitial lung disease associated with diffuse cutaneous systemic sclerosis?

1. Azathioprine

2. Cyclophosphamide

3. Nintedanib

4. Rituximab

The correct answer is: Cyclophosphamide

Interstitial lung disease (ILD) associated with diffuse cutaneous systemic sclerosis (scleroderma) is primarily characterized by inflammation and fibrosis of the lung tissue, leading to decreased lung function. The management of this condition often requires a combination of immunosuppressive therapy and disease-modifying agents aimed at reducing lung inflammation and preventing further fibrosis. Cyclophosphamide is a potent immunosuppressive drug that has been extensively studied for the treatment of scleroderma-related ILD. Its efficacy is particularly noted in patients with active disease, where it has been shown to improve lung function and reduce inflammation. Randomized trials have demonstrated that cyclophosphamide can stabilize or improve pulmonary function tests in patients with scleroderma-related ILD, making it a recommended treatment in clinical practice. On the other hand, while azathioprine and rituximab have been evaluated for use in scleroderma, cyclophosphamide remains the most evidence-based choice for directly addressing ILD in this context. Nintedanib, while effective in idiopathic pulmonary fibrosis, is not specifically indicated for treatment of ILD associated with systemic sclerosis. Therefore, the use of cyclophosphamide aligns with current guidelines and clinical evidence supporting its role in managing