A 60-year-old male with long-standing limited cutaneous systemic sclerosis develops progressive dyspnea on exertion and a dry cough. High-resolution computed tomography (HRCT) of the chest shows ground-glass opacities and honeycombing predominantly in the lung bases. Pulmonary function tests reveal a restrictive pattern with reduced diffusing capacity for carbon monoxide (DLCO). Which of the following is the most appropriate treatment for his pulmonary manifestation?

Explanation

The patient's symptoms, HRCT findings (ground-glass opacities, honeycombing), and PFTs (restrictive pattern, reduced DLCO) are consistent with interstitial lung disease (ILD), a common and serious complication of systemic sclerosis. Immunosuppressive agents like mycophenolate mofetil or cyclophosphamide are the mainstays of treatment for progressive SSc-ILD to slow disease progression. Nifedipine is used for Raynaud's phenomenon. Bosentan is an endothelin receptor antagonist used for pulmonary arterial hypertension, not primarily for ILD. Prednisolone monotherapy is generally not recommended for SSc-ILD due to limited efficacy and potential side effects, especially the risk of precipitating scleroderma renal crisis.