Interstitial pneumonitis in a patient with chronic hepatitis C and chronic renal failure on interferon therapy.

After 4-months of alpha interferon (IFN-α), a 64-year old woman with chronic hepatitis C developed a cough and dyspnea and showed diffuse infiltrative opacities on her chest X-ray. Her symptoms persisted after stopping the IFN-α therapy. Pulmonary function testing revealed a reduced forced vital capacity. High-resolution computed tomography of the lung showed peripheral and peribronchovascular ground glass attenuation and consolidation associated with reticulation. Bronchoalveolar lavage was performed for further evaluation and showed a lymphocyte level of 8.2%, an uncommon finding in IFN-α-induced interstitial pneumonitis. We performed a lung biopsy to diagnose her disease and it suggested interstitial pneumonitis. This was considered to be due to the immunomodulatory effects of INF-α. Although rare, any sign of significant pulmonary involvement should be evaluated.