Latent pulmonary involvement in Crohn's disease: biological, functional, bronchoalveolar lavage and scintigraphic studies.

Abstract

SUMMARYWe have investigated the following pulmonary related parameters in 22 patients with Crohn's disease who were free of clinical pulmonary symptoms and had normal chest roentgenograms and in 25 controls: serum angiotensin converting enzyme, pulmonary function tests, bronchoalveolar lavage (lymphocyte count and subpopulations, macrophage viability and superoxide anion release by macrophages) and pulmonary scannings. Serum angiotensin converting enzyme was lower in Crohn's disease (14-1±5 1) than in controls (25-2±4-7) (p<O-OO1). Twelve of 22 Crohn's disease (54%) had a bronchoalveolar lavage lymphocytosis (>18% alveolar lymphocytes). Bronchoalveolar lavage lymphocytes subpopulations were quite variable. Twelve of 17 Crohn's disease (71%) had an increase spontaneous and/or stimulated superoxide anion production by alveolar macrophages. Six of 12 Crohn's disease (50%) had an increase physiologic dead space in the upper part of their lung against one of 11 controls (9%). These data suggest that most patients with Crohn's disease have a latent pulmonary involvement.Systemic manifestations are frequent in inflammatory bowel disease, but classically the lung was regarded as rarely involved. 1 2 A few recent reports, however, have described pulmonary manifestations occuring in patients with inflammatory bowel disease: bronchial suppuration, or bronchiectasis,3-5 granulomatous lung disease,6 diffuse or localised interstitial fibrosis71-2 and sulphasalazine pneumonitis. 1321 The rarity of pulmonary clinical manifestations contrasts with striking abnormalities of pulmonary function tests described in patients with inflammatory bowel disease: reduced lung transfer factor, increased residual volume, or decreased forced expiratory volume in one second.22 26We have attempted to determine the actual frequency of pulmonary tests and bronchoalveolar abnormalities in patients with Crohn's disease and without clinical or radiological pulmonary abnormalities.27 28 Furthermore, we tried to clarify

Increased frequency of bronchial hyperresponsiveness in patients with inflammatory bowel disease

“…Although mild pulmonary impairments have been previously demonstrated in IBD, most studies have failed to find any difference in basal FEV 1 between IBD and control subjects (1,6,8). Our study confirms the absence of difference in basal bronchial caliber between the two groups.…”

“…Inflammation of the small airways may occur in IBD, induced by the bronchial homing of lymphocytes activated in the digestive tract. Alveolar lymphocytosis has been previously described in CD, although not in UC (1). In this perspective, the histopathology of the bronchial mucosa remains to be investigated.…”

“…However, subclinical abnormalities are present in about two-thirds of the patients. These abnormalities concern both the number and the activity of cells obtained after bronchoalveolar lavage (1) and the functional pulmonary parameters such as carbon monoxide-diffusing capacity (1,6,8).…”

Respiratory System Involvement in Inflammatory Bowel Diseases

“…Nevertheless, in 2009, the British researchers demonstrated that UC, but not CD, was more prevalent in the population of sarcoidosis patients compared to the general population [52]. Interestingly, serum angiotensin converting enzyme (sACE) activity in IBD patients was lower or the same as in the control group [36,53,54]. In the study confined to active IBD, sACE activity was significantly higher in UC patients compared to CD patients and healthy subjects, but was still significantly lower than in patients with acute sarcoidosis [55].…”

“…Fireman et al [35], on the other hand, found significantly higher lymphocyte count in induced sputum of non-smoking and respiratory symptoms free CD patients than in controls; in 65% of their patients, the CD4/CD8 lymphocytes ratio was higher than 2.5. Bonniere et al [36] compared BAL fluid of 22 patients with CD, free of clinical pulmonary symptoms and with normal chest roentgenograms, with 25 control subjects. Total number of cells in BAL fluid was identical, but percentages of lymphocytes were higher in patients than in controls.…”