Usefulness of monitoring of complement fragments in a patient with idiopathic interstitial pneumonia

Abstract

A 67 year-old female was admitted with dyspnea, dry cough and fever. Idiopathic interstitial pneumonia was diagnosed by a history of illness, findings of chest X-ray and computed tomography. She was improved once by the administration of antibiotics and steroid therapy. But about 2 months later she worsened clinically and died of respiratory failure despite treatment with a high dose of corticosteroid and antibiotics. Autopsy proved that she died not of pneumonia but of respiratory and cardiac failure that was brought about by acute progressive interstitial pulmonaly fibrosis.
In the clinical course we examined complement fragments, iC3b, Bb, C4d, C3a and C5a, those were drastically up and down in accordance with the clinical course. Those results suggested that complement and its fragments through activation may take a some kind of role in the pathogenesis of idiopathic interstitial pneumonia.