Airway lesions and superoxide dismutase (SOD) distribution in bronchopulmonary dysplasia (BPD)

We examined 71 cases of bronchopulmonary dysplasia (BPD) at autopsy and divided them into five groups on the basis of the patients' survival time, studying on the histological changes in the airways for the purpose of clarifying the pathogenesis of BPD from hyaline membrane disease (HMD). Furthermore, bronchiolar occlusion was classified into four types: secretion, obliterative bronchiolitis, intraluminal plug, and hyperplasia of bronchiolar components. The same occlusive findings as in bronchioli and hyaline membrane were observed from respiratory bronchioles to alveolar ducts. However, there was no obvious correlation between airway lesions and accompanying alveolar lesions excepts three cases of obliterative bronchiolitis. Furthermore, immunohistochemical studies with anti-human SOD antibodies were performed. Mn-SOD was positive for alveolar macrophages in longer surviving infants without significant correlation with histological variation, whereas slightly positive or negative in infants who died within 1 week; CuZn-SOD was rarely positive in any cases. These results is highly correlated to the pathogenesis of BPD and to its pathological advancement with its clinical course.     

Respiratory bronchiolitis: radiographic and CT findings in a pathologically proven case

A small number of cases of cigarette-smoking-associated respiratory bronchiolitis (RB) with positive findings on the chest radiograph have been reported in the literature. High-resolution computed tomography (HRCT) findings are available in even fewer cases. We describe the case of an asymptomatic female smoker presenting with a reticulomicronodular infiltrate on a routine chest radiograph. High-resolution CT was characterized by ground-glass opacities and centrilobular micronodules with an upper lobe predominance. Surgical biopsy revealed peribronchiolar lesions, with accumulation of brown pigmented macrophages in the lumen of alveolar and bronchiolar lumen, consistent with the pathologic diagnosis of RB.     

Neuroendocrine cell hyperplasia and obliterative bronchiolitis in patients with peripheral carcinoid tumors

Specimens from 25 consecutive patients undergoing lung resection for peripheral carcinoid tumor were examined for evidence of neuroendocrine cell hyperplasia and associated obliterative bronchiolitis. Where available, the CT scans (n = 11) were reviewed for evidence of multiple tumors, and pulmonary function data (n = 16) were reviewed for evidence of airflow obstruction. Nineteen of the 25 patients (76%) had neuroendocrine cell hyperplasia in addition to the dominant carcinoid tumor. Eight patients (32%) had lesions of obliterative bronchiolitis associated with foci of neuroendocrine cell hyperplasia, and two of these patients had asymptomatic airflow obstruction that could not be related to smoking or other lung disease. We conclude that multicentric neuroendocrine cell proliferation is common in patients with peripheral carcinoid tumor of the lung. Associated bronchiolar fibrosis occurs in a high proportion of such patients, but it is usually asymptomatic.     

The assessment of the severity of pulmonary edema by computed tomography. A comparison between high-resolution computed tomography, objective evaluation with density masks and functional tests

The results of high-resolution computed tomography (HRCT) were correlated with those of pulmonary function tests, chest films and CT expiratory density mask values in the evaluation of pulmonary emphysema in 33 symptomatic subjects. Emphysema was quantitated with both subjective and objective measurements. Conventional chest films were useful to diagnose severe emphysema but its actual extent was more reliably evaluated with CT scoring systems. HRCT and density mask correlated well with function tests, but the former method exhibited stronger correlation with carbon monoxide diffusion capacity. The opposite was true for hyperinflation and expiratory obstruction variables. Subjective CT estimates, which are quick and easy to perform, were seen to correspond more specifically to the pathophysiologic derangement and should therefore be used to evaluate the anatomic extent of disease. The functional severity of emphysema correlated only with the overall extent of disease and not with its regional distribution in the upper or lower lungs. Finally, in 4 cases (12.1%) with low CT scores, FEV1 was reduced but diffusion capacity values were normal. In one of these patients HRCT showed signs of bronchiolitis. In fact, small airway disease might be a more critical factor in determining functional impairment than the actual anatomical emphysema.     

A working formulation for the standardization of nomenclature and for clinical staging of chronic dysfunction in lung allografts. International Society for Heart and Lung Transplantation

A clinically applicable, standardized method for assessing functional results after lung transplantation is required to evaluate factors that may affect long-term outcome, to permit comparison of results from different centers, and to evaluate results of clinical trials. An ad hoc working group was established under the auspices of the International Society for Heart and Lung Transplantation for the purpose of developing such a clinically applicable system. Chronic allograft dysfunction is often associated with pathologic findings of obliterative bronchiolitis, the cause of which has not been defined. Physiologically, such dysfunction is associated with obstructive airways disease. The group concluded that the forced expiratory volume in 1 second was the most reliable and consistent indicator of graft dysfunction, excluding other identifiable causes. The term bronchiolitis obliterans syndrome was adopted to describe such dysfunction, recognizing that there may or may not be pathologic evidence of bronchiolitis obliterans present. Four stages of bronchiolitis obliterans syndrome were defined, each with two subcategories to indicate whether pathologic evidence of obliterative bronchiolitis had been identified. This working formulation will require reappraisal in the future to reassess its practical application and to make such adjustments as may seem appropriate.     

Pulmonary infection with Mycobacterium avium-intracellulare leads to air trapping distal to the small airways

To clarify the structure and function of the airways in Mycobacterium avium-intracellulare (MAI) infection, we performed pulmonary function tests and high-resolution computed tomography (HRCT) of the thorax in female patients 61 +/- 9 yr of age (n = 12) with pulmonary MAI infection without predisposing lung disease and compared their data with those of normal female volunteers 54 +/- 8 yr of age (n = 9). We calculated the E/I ratio, i.e., the average ratio of HRCT number at full expiration to that at full inspiration, as an index for the evaluation of air trapping distal to the small airways. Patients showed significant increases in residual volume and slope of phase III (DeltaN2) of the single-breath nitrogen test, and significant decreases in flow at 50 and 25% of FVC, suggesting hyperinflation and obstruction of the small airways. HRCT of patients revealed the small nodules and ectasis of bronchioles and small bronchi located mainly in segments (S) S2, S3, S4, and S5. The E/I ratio was significantly elevated in patients, and especially higher in the upper lung field than in the lower lung field, suggesting air trapping distal to the small airways. The difference of E/I ratio between the upper and lower field is probably related to the segmental distribution of CT abnormalities. These findings suggest that MAI infection can lead to air trapping distal to the small airways.     

Early changes of respiratory function in mitral valve stenosis

In order to detect early changes of respiratory function in patients affects by pure mitral valve stenosis, the authors selected 12 patients-non smokers, without symptoms of respiratory disease, of I and II NYHA class. In all subjects right and left cardiac catheterization and conventional spirometric measurements were performed. Then maximal mid-expiratory flow (MMEF), maximal expiratory flow at 50% of vital capacity (MEF 50%), maximal expiratory flow at 25% of vital capacity (MEF 25%), closing volume (CV) and closing capacity (CC) were determined, to find a small airways (bronchi of caliber inferior to 2 mm) disease. Whereas conventional spirometric measurements showed normal values, the small airways disease was proved by MEF 50% and MEF 25% measurements. The small airways obstruction observed by the authors may be due to: a) dilatation of pulmonary vessels because of venous congestion resulting in the compression of adjacent small airways; b) partial bronchiolar obstruction because of congestion of submucous venous plexus; c) interstitial oedema due to increase of extravascular pulmonary water because of pulmonary venous congestion.     

Peripheral airways as a determinant of ventilatory function in the human lung

We have investigated the morphological differences responsible for the variability in two tests of pulmonary function, maximal expiratory flow rates (MEF) and the frequency dependence of dynamic compliance (CDYN ratio). Functional measurements were obtained from 53 normal and minimally diseased postmortem human lungs. Morphological measurements performed on these same lungs included airway diameter at three levels in the bronchial tree, the amount of bronchial gland mass, and the alveolar surface to volume ratio. Multiple regression analysis suggests that the diameter of the peripheral conduction airways (membranous bronchioles) is the major morphological determinant for both MEF and the CDYN ratio in lungs at any particular age. Age-dependent changes in both functional tests were associated primarily with differences in the alveolar surface to volume ratio. Minimal emphysema and a lesion associated with cigarette smoking, respiratory bronchiolitis, have no demonstrable effect on either MEF or the CDYN ratio. These studies provide further evidence that the peripheral conducting airways are a major determinant of ventilatory function in the normal human lung.     

Expression of inducible nitric oxide synthase and formation of peroxynitrite in posttransplant obliterative bronchiolitis

BACKGROUND: Obliterative bronchiolitis is characterized histologically by inflammation, epithelial cell damage and loss, fibrosis, and eventual obliteration of airways. Production of high levels of the potential cytotoxin nitric oxide by inducible nitric oxide synthase has been implicated in several inflammatory diseases. The damaging effects of nitric oxide are mediated by peroxynitrite, are formed from nitric oxide and superoxide, and can be demonstrated by the detection of nitrotyrosine. Our previous finding of high inducible nitric oxide synthase expression in inflamed airway epithelium led us to hypothesize that release of nitric oxide in obliterative bronchiolitis mediates the characteristic epithelial damage. METHODS: Immunocytochemistry was carried out to seek expression of inducible nitric oxide synthase and nitrotyrosine in transplant samples from patients with obliterative bronchiolitis (n=10) and, as controls, unused donor lungs (n=5). RESULTS: Inducible nitric oxide synthase was strongly expressed in the damaged airway epithelium in obliterative bronchiolitis and in inflammatory cells, where its distribution was matched by that of nitrotyrosine. Normal controls showed little or no immunoreactivity for any of the antigens studied. CONCLUSIONS: Our findings suggest that nitric oxide may play a role in the pathogenesis of obliterative bronchiolitis and indicate that further work is essential to fully understand the processes and mechanisms involved.     

The diagnostic accuracy of high-resolution computed tomography in diffuse infiltrative lung diseases

The purpose of this study was to evaluate the role of high-resolution computed tomography (HRCT) in the clinical diagnosis of diffuse infiltrative lung disease (DILD). Diagnostic accuracy was compared using both chest radiography and HRCT. One hundred thirty-four cases of DILD, representing 21 different diseases, were selected for study, and the disease state was confirmed either histologically or microbiologically. The HRCT images and chest radiographs, available in all cases, were reviewed separately and in random order by 20 physicians who were provided only with information on each patient's age and sex. Overall, a correct first-choice diagnosis was made in 38 percent using radiographs and in 46 percent using HRCT images (p < 0.01). The correct diagnosis was among the top three choices in 49 percent when chest radiographs were used, and in 59 percent when HRCT images were viewed (p < 0.01). The correct first-choice diagnosis increased remarkably when the HRCT was used in usual interstitial pneumonia, sarcoidosis, alveolar proteinosis, bronchiolitis obliterans organizing pneumonia, hypersensitivity pneumonitis, and pulmonary lymphangiomyomatosis. High-resolution computed tomography was confirmed to be superior to conventional radiography in the accurate diagnosis of DILD in clinical practice.     

Pulmonary sarcoidosis: morphologic associations of airflow obstruction at thin-section CT

PURPOSE: To identify relationships between the obstructive defects of pulmonary sarcoidosis and the computed tomographic (CT) patterns of disease. MATERIAL AND METHODS: CT scans obtained in 45 patients were scored semiquantitatively for extent of five CT patterns, and the functional importance of each pattern was evaluated. RESULTS: The most prevalent CT patterns were decreased attenuation (n = 40), a reticular pattern (n = 37), and a nodular pattern (n = 36). At univariate and multivariate analyses, a reticular pattern was the main determinant of functional impairment, particularly airflow obstruction. The extent of a reticular pattern was independently associated with airflow obstruction, as shown by the inverse relationships with the forced expiratory volume in 1 second (FEV1) (P < .001), FEV1-forced vital capacity ratio (P < .01), maximum expiratory flow at 25% above residual volume (P < .001), and maximum expiratory flow at 50% above residual volume (P < .001) and the positive relationship with the residual volume-total lung capacity ratio (P < .001). CONCLUSION: In sarcoidosis, CT features compatible with small airways disease are common but contribute little to airflow obstruction, particularly in more advanced disease, which is characterized by an extensive reticular pattern. A reticular pattern at CT is the major morphologic association of airflow obstruction.     

Lobular low attenuation of the lung parenchyma on CT: evaluation of forty-eight patients

PURPOSE: Our goal was to analyze patients with pulmonary lobular low attenuation (LLA) on thin section CT with regard to the underlying pulmonary diseases and the dynamic changes occurring in the low attenuation regions during respiration. METHOD: Forty-eight consecutive patients with LLA on thin section CT were analyzed retrospectively. Forty-six patients (95%) had symptoms related to respiratory disease, such as productive cough (n = 25) and hemoptysis (n = 18). Only two patients, one with chronic pulmonary embolism and one with Takayasu arteritis combined with bronchiectasis, had pulmonary vascular disease. Six patients, four with bronchiectasis and two with vascular disease, were studied with dynamic CT during forced vital capacity maneuver. Attenuation values for LLA areas and adjacent lung were measured and time-density curves were plotted. RESULTS: Forty-one (85%) patients had bronchiectasis, typically in other than the regions of the LLA. Areas with proximal bronchiectasis showed low attenuation but without notable lobular distribution. Pulmonary vessels in the LLA areas were smaller than those of adjacent normal lung (n = 45). Of 22 patients who underwent pulmonary function tests, 15 had obstructive pattern of impairment. Respiratory dynamic CT showed expiratory air trapping in LLA areas in all six patients. The mean attenuation values of LLA areas were lower than those of the adjacent normal lung by 67 HU at end-inspiration and by 165 HU at end-expiration (p = 0.002). CONCLUSION: The majority of the patients with LLA shown by thin section CT had bronchiectasis elsewhere in the lung, and evidence of air trapping in the LLA was clearly demonstrated. Bronchiolar obstruction may be the most prevalent cause for the development of LLA.     

Constrictive (obliterative) bronchiolitis: diagnosis, etiology, and a critical review of the literature

Constrictive bronchiolitis (CB) (or obliterative bronchiolitis) designates inflammation and fibrosis occurring predominantly in the walls and contiguous tissues of membranous and respiratory bronchioles, with resultant narrowing of their lumens. It differs from bronchiolitis obliterans-organizing pneumonia in its histopathology and clinical course. Most cases of CB occur in the setting of organ transplants, particularly lung and heart-lung transplants, but also in bone marrow transplants. Other bona fide cases are rare: infection, particularly viral infection, appears to be a well-documented precursor to CB in children, but not in immunocompetent adults. Constrictive bronchiolitis also has been reported in the course of rheumatoid arthritis, in certain other autoimmune diseases such as pemphigus vulgaris, after inhalation of toxic gases such as nitrogen oxide, after ingestion of certain drugs or medicinal agents such as Sauropus androgynous, and as a cryptogenic illness. Recent reports suggest that CB, as defined by clinical criteria (that is, bronchiolitis obliterans syndrome), is very common in lung allograft recipients who survive more than 5 years and, although it is associated with significant mortality, it also can be clinically stable. Furthermore, with the current practice of close monitoring of these patients, it appears that CB may now be diagnosed at an earlier stage, at which resolution, or at least stabilization of progression, is possible. A histopathologic diagnosis of CB in lung transplant and other patients may be difficult to make due to the patchy distribution of lesions, the technical difficulty in obtaining tissue in late lesions with extensive fibrosis, and the failure to recognize lesions. With regard to the last of these, in early stages of disease, CB may be subtle and easily missed in routine hematoxylin-eosin-stained specimens, while in advanced stages the disease may be equally difficult to diagnose if the patchy scarring in the lung is interpreted as nonspecific. The relative loss of bronchioles and the relationship of the scars to contiguous arteries should signal the need for elastic stains to look for the residual elastica of the bronchioles amidst the foci of fibrosis. Increasingly, clinical grounds, including pulmonary functions studies and high-resolution computed tomography findings, are proving to be relatively sensitive methods of detecting CB. Finally, the progressive airway destruction in chronic transplantation rejection appears to be a T-cell-mediated process. The "active" form of constrictive bronchiolitis, with attendant lymphocytic inflammation of the airways, likely precedes the "inactive" or scarred form of constrictive bronchiolitis.     

Digital color imaging colposcopy: a matter of choice

PURPOSE: The objective of this study was to correlate the findings of sarcoidosis on high resolution CT (HRCT) with indexes of disease activity as measured with 67Ga scan, bronchoalveolar lavage (BAL), and serum angiotensin-converting enzyme (SACE) assay. METHOD: Twenty-nine patients with proven sarcoidosis underwent HRCT scan, 67Ga scan, BAL, and SACE assay within a 1 month period. The extent of parenchymal involvement by nodules, consolidation, ground-glass attenuation, and linear opacities was quantified to the nearest 10% of surface area affected on the CT examination. Whole-lung gallium uptake was quantified and the percentage of BAL-recovered lymphocytes (BAL-%LC) and SACE levels obtained by chart review. CT scores of disease extent were correlated with measured indexes of activity using the Spearman rank correlation coefficient. RESULTS: The mean extent of nodules, consolidation, ground-glass attenuation, and linear opacities on HRCT images was 15.1 +/- 16.6, 1.6 +/- 4.0, 17.5 +/- 25.4, and 7.6 +/- 9.6%, respectively. The extent of nodules and consolidation correlated with the intensity of lung gallium uptake (r = 0.46, p < 0.02), BAL-%LC (r = 0.50, p < 0.01), and SACE levels (r = 0.38, p < 0.05). No significant correlation was found between extent of ground-glass attenuation or linear opacities with any indexes of disease activity. CONCLUSION: On HRCT scan, nodules and consolidation in sarcoidosis reflect disease activity as measured by 67Ga scan, BAL, and SACE assay.     

Density dependence of pulmonary resistance: correlation with small airway pathology

The density dependence of maximal expiratory flow is not an effective test of the site of airway narrowing in obstructive lung disease. We hypothesized that the density dependence of pulmonary resistance (DD,RL) would be more closely related to the degree of airway narrowing and peripheral airway pathology in smokers. We measured maximal expiratory flow at 50% vital capacity (V'max50) and lung resistance (RL) breathing air and 80% helium-20% oxygen, and calculated density dependence of V'max50 and RL in 40 patients who had moderate airflow obstruction and in 10 normal subjects. We compared the density dependence of RL and V'max50 with the degree of airway obstruction and bronchiolar pathology scores in 27 patients with resected lung specimens. There were no differences in DD of V'max50 or RL between normal subjects and patients, and no relationship between the degree of obstruction or the bronchiolar pathology score and the DD of these measurements. There were significant relationships between V'max50, RL and the bronchiolar pathology scores. In conclusion, lung resistance and maximal expiratory flow are related to the severity of peripheral airway pathology, but there is no relationship between the severity of obstruction or the severity of peripheral airway pathology and the density dependence of maximal expiratory flow or lung resistance.     

The arthroscopic appearance of lipoma arborescens of the knee

March, 1991, to June, 1992, five lung transplantations for end-stage lung disease were successfully performed at the Ospedale Maggiore Policlinico in Milan. All patients underwent high-resolution CT (HRCT) of the lung in a complex follow-up program to identify specific abnormalities of acute and chronic rejection (bronchiolitis obliterans) and to monitor the resolution of the bronchial anastomosis. Twenty-two HRCT exams were performed. In patients with acute rejection HRCT failed to identify specific abnormalities of lung parenchyma. In contrast, in one patient with pathological evidence of early bronchiolitis obliterans HRCT showed decreased peripheral vascularization. In the study of the bronchial anastomosis, HRCT showed optimal anastomosis resolution in 4 patients, whereas in one patient with a granuloma demonstrated by fibrobronchoscopy it confirmed the lesion showing also a small pneumomediastinum. Even though the HRCT finding of decreased peripheral vascularization does not appear to be specific for bronchiolitis obliterans, it may be of value in suggesting the diagnosis of early bronchiolitis obliterans in lung transplant. HRCT should be used in all patients with bronchoscopic diagnosis of bronchial complication to study the lesion and its mediastinal spread.     

Surgical margins and prognostic factors in patients with thick (>4mm) primary melanoma

PURPOSE: The aim of this project was to analyze and validate the diagnostic applications of Volumetric High Resolution CT in the study of focal or diffuse infiltrative lung disease compared with High Resolution CT. To date HRCT is the gold standard in the assessment of infiltrative lung diseases, but it shows some limitations such as artifacts due to both respiratory and cardiac motions, as well as the need for multiple breath-holds. MATERIAL AND METHODS: September, 1996, to September, 1997, anthropomorphic test phantoms and a group of 34 subjects (8 without lung disease and 26 with aspecific lung disease: TBC, BPCO, micronodular conditions, cardiogenic interstitial pulmonary edema) were submitted to both HRCT and VHRCT. VHRCT was carried out with a 3-mm slab thickness and the images were reconstructed with a 1-mm interval and processed with MIP and MinIP reconstructions. With both techniques we compared some physical parameters (slice sensitivity profile, noise, longitudinal resolution) and some radiographic findings (central and peripheral airways lumen, peripheral vessels, nodular and interstitial abnormalities, emphysema foci, focal areas of ground glass pattern and bronchiectasis). We calculated the radiation exposure dose of both HRCT and VHRCT, also testing a low-dose protocol. RESULTS: The analysis of physical parameters showed no major differences between HRCT and VHRCT regarding longitudinal resolution, while minimal advantages were found with HRCT for slice sensitivity profile and image noise. Radiographic analysis showed additional findings in 27% of patients with nodular disease using VHRCT-MIP in 8% of patients with emphysema and 25% of cases with focal areas of ground glass opacities, using VHRCT-MinIP. Relative to HRCT findings, VHRCT better depicted all patterns but subpleural nodules. The surface radiation dose was 2.8 times higher with VHRCT than HRCT. It is possible to halve radiation exposure using a low dose protocol (120 kV, 110-150 mA). CONCLUSIONS: Our study provides conclusive results concerning the use of VHRCT with standard technical parameters because this technique showed some advantages in the study of a wide range of diffuse or focal lung diseases. We suggest that this protocol be applied only in patients with mild forms of lung disease or in the cases of difficult interpretation, such as suspicious abnormal areas at HRCT, because its doses are higher. Out low-dose protocol is currently on trial but we expect promising results.     

Bronchial adenoma resection with relief of hypoxic pulmonary vasoconstriction

Experimental airway obstruction is known to cause reflex pulmonary artery constriction, but clinical documentation of reversible bronchial obstruction and vasoconstriction is rare. A soft bronchial adenoma obstructed the left main bronchus, and scans showed minimal ventilation and perfusion on the left. Gas aspirated from beyond the tumor was hypoxic. The adenoma was removed and the lung left intact by means of a skin graft in the bronchial wall. Four months later, pulmonary function was normal, and both ventilation and perfusion of the left lung were normal. Reflex pulmonary vasoconstriction resulting from alveolar hypoxia minimizes systemic hypoxemia and also minimizes alveolar tissue hypoxia in the lung itself. The reflex is seen most frequently in perfusion scans in patients with chronic airways disease. This case in important in that it documents reversal of vasoconstriction after ventilation was restored.     

Changes in the respiratory system of patients with rheumatoid arthritis--personal observations

13 patients with RA admitted to our Institute with symptoms of respiratory involvement were described. Taking under consideration pulmonary function tests, radiological findings and histological examinations, we recognised 7 cases with interstitial lung disease, 3 cases with recurrent respiratory infection with bronchiectasis, 1 case with pleuritis, 1 with Caplan's syndrome and 1 with alveolar haemorrhage. The role of RF, and treatment with gold in the development of interstitial lung disease, as well as character of physiologic abnormalities concerning the small airways and its potential connection with bronchiolitis were discussed.     

Bronchiolitis obliterans syndrome: thin-section CT diagnosis of obstructive changes in infants and young children after lung transplantation

PURPOSE: To characterize the thin-section computed tomographic (CT) appearance of bronchiolitis fibrosa obliterans syndrome in infants and young children after lung transplantation. MATERIALS AND METHODS: Thin-section CT studies in six patients with bronchiolitis obliterans syndrome (age range, 2 months to 5 1/2 years) and in 15 control patients without obstructive airway disease (age range, 2 months to 7 years) who underwent bilateral lung transplantation were retrospectively reviewed. The thin-section CT scans were obtained during quiet sleep at a median of 24 months (range, 6-36 months) after transplantation. The CT studies were evaluated for mosaic perfusion, bronchial dilatation, bronchial wall thickening, and mucous plugging Final diagnoses in all patients were based pulmonary function test results. RESULTS: Thin-section CT findings in the six patients with clinically proved bronchiolitis obliterans syndrome were mosaic perfusion in five (83%) bronchial dilation in three (50%), and bronchial wall thickening in one (17%). Of the 15 control patients with normal pulmonary function test results, six (40%) had mosaic perfusion; none had bronchial dilatation or bronchial wall thickening. Mucous plugging was not seen in either group. Only the association of bronchial dilatation with bronchiolitis obliterans syndrome was significant (P = .02). CONCLUSION: Infants and young children with bronchiolitis obliterans syndrome after lung transplantation are more likely to have CT abnormalities than those with normal pulmonary function test results.