Update in Pulmonary Medicine

Interstitial Lung Disease

Combination Therapy with Corticosteroids and Cyclophosphamide Was No More Effective than No Therapy in Patients with Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) affects an estimated 1 million people worldwide. Scientists long believed that IPF (also known as usual interstitial pneumonia, the name that pathologists give to the associated histologic pattern) represented fibrosis that resulted from an inflammatory reaction. Recent research, however, has shown that inflammation is not a prominent feature in early disease and does not appear to be a precursor to fibrosis (1). Investigators now believe that the disease represents a dysregulated fibrotic response to alveolar injury, and this abnormal response may originate in epithelial cell repair or cytokine signaling mechanisms (1). Cigarette smoking may be a risk factor, but no other factors have been clearly identified. Patients typically have dry bibasilar crackles (“Velcro crackles”) and often have clubbing of the fingers. Diagnosis is made by high-resolution computed tomography (CT) or by lung biopsy.

Treatment responses are disappointing. Fewer than one third of patients respond to corticosteroid therapy alone; consequently, some physicians add a cytotoxic agent (either azathioprine or cyclophosphamide) to the regimen. Because treatment is often ineffective and is associated with severe adverse effects (2), other physicians feel that withholding therapy is ethically reasonable. Some prospective studies that compared combination corticosteroid and immunosuppressive treatment with corticosteroid therapy alone have shown no benefit to combination therapy. However, no prospective study has compared this type of combination therapy with no treatment.

Collard and associates retrospectively compared combination therapy and no …