In Japan, chronic bronchitis with severe obstruction and without emphysema is found in nonsmoking adults. This is a progressive lung disease with a poor prognosis and is frequently accompanied by Pseudomonas aeruginosa infection, showing diffuse linear and reticulonodular shadows on the chest radiograph. It has been called diffuse panbronchiolitis by Homma et al1Homma H Yamanaka A Tanimoto S Tamura M Chijimatsu Y Kira S et al.Diffuse panbronchiolitis: a disease of the transitional zone of the lung.Chest. 1983; 83: 63-69Abstract Full Text Full Text PDF PubMed Scopus (343) Google Scholar and has not been reported in white patients. The clinical features resemble those found in adult patients with mild cystic fibrosis (CF), an inherited disorder in white persons but with minimal or little pancreas dysfunction and intermediate-range sweat chloride concentration.2Stern RC Boat TF Abramowsky CR Matthew LW Wood RE Doershuk CR. Intermediate-range sweat chloride concentration and Pseudomonas bronchitis: a CF variant with preservation of pancreas function.JAMA. 1978; 239: 2676-2680Crossref PubMed Scopus (7) Google Scholar Although Sugiyama et al3Sugiyama Y Kudoh S Maeda H Suzuki H Takaku F. Analysis of HLA antigens in patients with diffuse panbronchiolitis.Am Rev Respir Dis. 1990; 141: 1459-1462Crossref PubMed Scopus (121) Google Scholar have implicated a genetic background for this disease, our results based on delta F508 mutation analysis of the CF gene indicate that the chronic bronchitis may represent a disease different from CF.4Akai S Okayama H Shimura S Tanno Y Sasaki H Takishima T. Delta F508 mutation of cystic fibrosis gene is not found in chronic bronchitis with severe obstruction in Japan.Am Rev Respir Dis. 1992; 146: 781-783Crossref PubMed Scopus (35) Google Scholar Thus, in Japan, pure chronic bronchitis with severe obstruction and without pulmonary emphysema is very common. The pathologic findings of this type of chronic bronchitis are well described in many previous reports in English that show the absence of emphysematous changes in spite of severe obstructive impairment and right ventricular hypertrophy.1Homma H Yamanaka A Tanimoto S Tamura M Chijimatsu Y Kira S et al.Diffuse panbronchiolitis: a disease of the transitional zone of the lung.Chest. 1983; 83: 63-69Abstract Full Text Full Text PDF PubMed Scopus (343) Google Scholar,5Aoki T Inoue H Sasaki H Shimura S Maeda S Tomioka M et al.Relation between selective alveolo-bronchograms and pulmonary function tests in patients with chronic obstructive lung disease.Am Rev Respir Dis. 1984; 129: 465-472PubMed Google Scholar, 6Honda I Shimura S Sasaki T Sasaki H Takishima T Nakamura M. Airway mucosal permeability in chronic bronchitis and bronchial asthmatics with hypersecretion.Am Rev Respir Dis. 1998; 137: 866-871Crossref Scopus (9) Google Scholar, 7Aikawa T Shimura S Sasaki H Takishima T Yaegasi H Takahashi T. Morphometric analysis of intraluminal mucus in airways in obstructive lung disease.Am Rev Respir Dis. 1989; 140: 477-482Crossref PubMed Scopus (81) Google Scholar As pointed out by Dr. Snider in his comment on our report, such pure chronic bronchitis is rare in the United States and European countries. However, this chronic bronchitis is a good clinical model for understanding the bronchial or airway lesions in COPD because of the absence of pulmonary emphysema. The obtained findings will also be useful for the management of COPD patients in the United States and European countries. Perivascular Fibrosis of Muscular Pulmonary Arteries in COPDCHESTVol. 105Issue 3PreviewThe article by Andoh and colleagues,1 which appeared in the December 1992 issue of Chest, is a useful addition to the literature on cor pulmonale in COPD. Its contribution to the larger understanding of COPD would be considerably enhanced if some additional information could be provided. Full-Text PDF