Kitaichi, Masanori

AbstractBackground and objectiveDespite significant recent progress in the understanding of idiopathic pulmonary fibrosis (IPF), the early phase of the disease is still poorly understood. We studied patients with IPF without pulmonary function impairment in order to determine the clinical features, natural history and key findings for physiological progression.MethodsTwenty‐five patients without pulmonary function impairment were identified from among patients with previously diagnosed IPF who underwent surgical lung biopsies between January 1997 and December 2006 at our institutions. ‘Without pulmonary function impairment’ was defined as both forced vital capacity (FVC) and diffusing capacity for carbon monoxide (DLco) >80% predicted. Patients diagnosed with IPF through multidisciplinary discussion based on the new IPF guidelines were the subjects of this study.ResultsSixteen patients had a confirmed diagnosis of IPF. Eleven patients presented with chest X‐ray abnormality found during an annual health examination. Seven patients were asymptomatic. Eleven patients showed physiological disease progression (median time; 19.9 ± 12.3 months) defined by a decline of at least 10% in FVC or at least 15% in DLco. Univariate analysis revealed that both usual interstitial pneumonia pattern and extent of honeycombing on high‐resolution computed tomography (HRCT) were factors associated with disease progression (odds ratio 5.634, 95% confidence interval 1.364–23.278; odds ratio 2.371/5%, 95% confidence interval 1.042–5.395).ConclusionsIPF patients without pulmonary function impairment have a progressive but slow clinical course. The existence and extent of honeycombing on HRCT are predictive of disease progression.

Abstract Rationale The 2002 American Thoracic Society/European Respiratory Society classification of idiopathic interstitial pneumonias identified nonspecific interstitial pneumonia (NSIP) as a provisional diagnosis. Concern was expressed that NSIP was a “wastebasket” category, difficult to distinguish from other idiopathic interstitial pneumonias. Objectives The following questions were addressed: (1) Is idiopathic NSIP a distinct entity? 2) If so, what are its clinical, radiologic and pathologic characteristics? (3) What is the role of radiology and pathology in establishing the diagnosis? (4) To make a diagnosis of idiopathic NSIP, what other disorders need to be excluded and how should this be done? Methods Investigators who had previously reported cases of idiopathic NSIP were invited to submit cases for review (n = 305). After initial review, cases with complete clinical, radiologic, and pathologic information (n = 193) were reviewed in a series of workshops. Measurements and Main Results Sixty-seven cases were identified as NSIP. Mean age was 52 years, 67% were women, 69% were never-smokers, and 46% were from Asian countries. The most common symptoms were dyspnea (96%) and cough (87%); 69% had restriction. By high-resolution computed tomography, the lower lung zones were predominantly involved in 92% of cases; 46% had a peripheral distribution; 47% were diffuse. Most showed a reticular pattern (87%) with traction bronchiectasis (82%) and volume loss (77%). Lung biopsies showed uniform thickening of alveolar walls with a spectrum of cellular to fibrosing patterns. Five-year survival was 82.3%. Conclusions Idiopathic NSIP is a distinct clinical entity that occurs mostly in middle-aged women who are never-smokers. The prognosis of NSIP is very good.

Abstract Background To investigate whether the better prognosis of interstitial pneumonias associated with collagen vascular disease (CVD) compared with idiopathic interstitial pneumonia (IIP) is due to higher frequency of the nonspecific interstitial pneumonia (NSIP) pattern in CVD, we compared the outcomes of patients from these two groups with the same histopathologic pattern. Subjects The clinical features and survival of 362 patients (269 with IIP and 93 with CVD) diagnosed using surgical lung biopsy were analyzed. Results The mean survival of the CVD group (131.0 mo) was longer than that of the IIP group (80.5 mo) (p < 0.0001). The patients with usual interstitial pneumonia pattern among the CVD group (n = 36) was younger, female, and predominantly nonsmoking compared with the IIP group (n = 203). Although baseline lung functions were not significantly different, the CVD group survived longer (mean, 177.0 mo) than the IIP group (mean, 66.9 ± 6.5 mo; p = 0.001). By multivariate analysis, younger age, better pulmonary function, and the presence of a CVD were independent prognostic factors. In NSIP pattern, no significant differences in survival, clinical features, or lung function were found between the two groups. Conclusion Our data suggest that the better prognosis of patients in the CVD group is not solely due to the predominance of the NSIP pattern. The prognosis of patients with the usual interstitial pneumonia pattern in CVD is better than in those with idiopathic pulmonary fibrosis, despite the same pathologic pattern. In contrast, in those with an NSIP pattern, the prognosis is similar in both groups.

Abstract The histopathologic pattern provides the most important prognostic marker for idiopathic interstitial pneumonia; however, studies have suggested that short-term changes in lung function may be more important. We investigated the prognostic factors for fibrotic interstitial pneumonia. The clinical features and follow-up course of 179 patients (131 with idiopathic pulmonary fibrosis and 48 with nonspecific interstitial pneumonia; 41 fibrotic types and 7 cellular) were analyzed retrospectively. The lung function indices improved or stabilized in most patients with fibrotic nonspecific interstitial pneumonia in contrast to the deterioration or stable condition of most patients with idiopathic pulmonary fibrosis. The 5-year survival of patients with fibrotic nonspecific interstitial pneumonia (76.2%) was better than for those with idiopathic pulmonary fibrosis (43.8%) (p = 0.007). Multivariate analysis at the time of presentation revealed that pathologic pattern, age, and diffusion capacity had important prognostic implications. However, after 6 months of follow-up, changes in FVC, initial diffusion capacity, and sex were the only independent prognostic factors, with no additional prognostic information conferred by the histologic diagnosis. Our data confirmed the importance of physiological parameters including short-term change in FVC. However, at the time of diagnosis, histopathology was important for the prediction of prognosis and future change in lung function.