[Siblings with familial interstitial pneumonia].

The index case was a 71-year-old man with no smoking history. He was given a diagnosis of idiopathic interstitial pneumonia at the age of 65. He was admitted to our hospital because of persistent cough and dyspnea on exertion. Two months after initiation of corticosteroid treatment he died of acute exacerbations of interstitial pneumonia. Among his family, four of seven brothers had interstitial pneumonia and all three sons of his were also found to have interstitial pneumonia, and of these seven patients six had a history of smoking. The average age at diagnosis of his generation was 66.5 and that of his son's generation was 45.3. In proband generation chest CT showed traction bronchiectasis or honeycombing in subpleural lesions. In addition, it revealed centrilobular micronodules and interlobular reticular shadow in the second generation. We found 2 single nucleotide polymorphisms of surfactant protein C gene in all children of the proband.