Chest
Volume 127, Issue 1, January 2005, Pages 178-184
Journal home page for Chest

Clinical Investigations: Interstitial Lung Disease
Desquamative Interstitial Pneumonia and Respiratory Bronchiolitis-Associated Interstitial Lung Disease

https://doi.org/10.1378/chest.127.1.178Get rights and content

Background

Desquamative interstitial pneumonia (DIP) and respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) are uncommon forms of interstitial lung disease and have been incompletely characterized.

Study objectives

To further characterize the clinical features and course of subjects with DIP and RB-ILD.

Design

Retrospective study.

Setting

Tertiary care, referral medical center.

Patients

Twenty-three subjects with DIP and 12 subjects with RB-ILD seen over a 12-year period between 1990 and 2001.

Interventions

None.

Results

The study population included 19 men (54%) and 16 women (46%). The mean (± SD) age at diagnosis was 46 ± 10 and 43 ± 7 years, respectively, for patients with DIP and RB-ILD. All subjects were either current or previous smokers except for three subjects with DIP. The diagnosis was confirmed in all cases by surgical lung biopsy. Bronchoscopy with transbronchial lung biopsy had been performed in 12 patients and was nondiagnostic in all. The most common pulmonary function abnormality was a reduced diffusing capacity of the lung for carbon monoxide. A CT scan of the chest revealed ground-glass opacities bilaterally in most patients who had DIP and RB-ILD. No differences were observed between subjects with DIP and RB-ILD with respect to clinical features, radiologic findings, or pulmonary function test results. The clinical course was characterized by relative stability in the majority of patients in both groups and a partial response to corticosteroid therapy. Five deaths were observed, including three resulting from progressive diffuse lung disease, all in subjects with DIP.

Conclusions

We concluded that DIP and RB-ILD are chronic disease processes that in most patients are related to smoking. Persistent abnormalities can be seen on pulmonary function testing and radiologic studies despite smoking cessation and corticosteroid therapy. Corticosteroid therapy appeared to be associated with modest clinical benefit but usually not with resolution of disease. Progressive disease with eventual death can occur in subjects with DIP, especially with continued cigarette smoking.

Section snippets

Materials and Methods

We conducted a computer-assisted search of the Mayo Clinic database to identify cases of DIP and RB-ILD that were seen at our institution over a 12-year period between January 1, 1990, and December 31, 2001. All lung biopsy specimens were reviewed to confirm the histopathologic pattern of either DIP or RB-ILD.

RB-ILD was defined by the presence of clinical and radiologic evidence of ILD occurring in a patient with histologically proven respiratory bronchiolitis (RB) seen on a surgical lung

Results

We identified 23 patients with DIP and 12 patients with RB-ILD who were seen at our institution over a 12-year period between 1990 and 2001. The mean (± SD) duration of follow-up from the initial visit at our medical center with diagnosis was 19.6 ± 29.5 and 11.8 ± 16.5 months, respectively, for subjects with DIP and RB-ILD. The mean duration of follow-up from the time of surgical biopsy was 37.7 ± 44.6 and 17.3 ± 15.4 months, respectively, for subjects with DIP and RB-ILD. Bronchoscopy with

Discussion

DIP and RB-ILD are relatively uncommon forms of ILD that are strongly associated with cigarette smoking. Our study confirms the preponderance of smokers among subjects diagnosed with either DIP or RB-ILD. Others have demonstrated a history of smoking in about 90% of patients.1314 In never-smokers, DIP is occasionally observed to be associated with other conditions, including connective tissue diseases and drug-induced lung disease.9 A lesion resembling DIP has been described14 in infants with

References (24)

  • International Multidisciplinary Consensus Classification of the idiopathic interstitial pneumonias

    Am J Respir Crit Care Med

    (2002)
  • MoonJ et al.

    Clinical significance of respiratory bronchiolitis on open lung biopsy and its relationship to smoking related interstitial lung disease

    Thorax

    (1999)
  • Cited by (0)

    This research was supported by Mayo Institutional funds and the Robert N. Brewer Family Foundation.

    Reproduction of this article is prohibited without written permission from the American College of Chest Physicians (e-mail: [email protected]).

    View full text