Objectives: Interferon (IFN)-induced lung injury is a rare but severe complication. Studies are needed to elucidate the demographic characteristics, clinical manifestations, and prognostic features of IFN-induced interstitial lung disease (ILD).
Case report: We report a patient with chronic hepatitis who developed ILD after interferon monotherapy. To further clarify the clinical characteristics of such patients, we searched for cases in which lung injury was documented as a side effect of hepatitis treatment and systematically analyzed all case reports for clinical manifestations, type of treatment, and outcomes.
Results: This is a 61-year-old male with a previous medical history of chronic hepatitis B. After 2 months of pegylated-interferon alpha (PEG-IFNα) application, he gradually developed cough and exertional dyspnea. Repeated chest images suggested progressive ILD, and lung biopsy revealed subacute lung injury. The diagnosis of PEG-IFNα-induced ILD was made. Including our case, 35 articles containing 45 patients were involved in our review. IFN-induced ILDs, often with a subacute onset, are characterized by nonproductive cough, dyspnea, and pulmonary infiltrates on chest radiograph. Most patients(62%, 28/45) required additional systemic steroid, and 5 (11%) patients who were co-administered ribavirin died of ILD progression despite steroid treatment.
Conclusion: Although rare, IFN-induced ILD can lead to decreased lung function, and sometimes become fatal despite intensive treatment. Most previously reported cases were with chronic hepatitis C, and most of the medication was in combination with ribavirin. IFN-induced ILD should be monitored during IFN therapy, and appropriate steroid is recommended in patients with progressive manifestations.