Airway Obstruction in Rheumatoid Arthritis: CT Manifestations, Correlated with Pulmonary Function Testing

In the present study, the signs of airflow obstruction on inspiratory and expiratory CT scans in 45 patients with rheumatoid arthritis were investigated. Radiologic findings were evaluated and correlated with the clinical data, which included rheumatoid factors and pulmonary function tests results. A lung biopsy was performed in five patients. The pattern of CT findings was as follows: infiltrative (n=15), obstructive (n=12), mixed (infiltrative and obstructive; n=10), other complicating diseases (n=7), and normal (n=1). The rheumatologic factor between patients with bronchial wall thickenings and patients without thickenings was significantly different (p=0.009). The forced expiratory flow rate between 25% and 75% of the vital capacity (FEF25-75%) was significantly more reduced in patients with interlobular septal thickenings than in patients without these thickenings. The patients with mosaic attenuation had significantly lower mean values of FEF25-75% (p=0.001) and a lower peak expiratory flow (p=0.003) than patients without mosaic attenuation. On expiratory scans, the mean air-trapping score was 21%. These air-trapping scores were found to be well correlated with FEV1/FVC (r=0.230, p=0.0452), and FEF25-75% (r=-0.63, p= 0.05). It is widely known that a relatively higher percentage of mosaic attenuation with air-trapping and a good correlation between these and functional values contribute to the detection of early airway obstruction in patients with rheumatoid arthritis, and even in patients with infiltrative lung disease only.

Determination of the Activity of Pulmonary Tuberculosis: the Utility of High-Resolution Computed Tomography

PURPOSE: To evaluate the utility of high-resolution computed tomography(HRCT), as used to determine the activity of tuberculosis, and to analyze the HRCT findings in active and in inactive tuberculosis. MATERIALS AND METHODS: We analyzed the HRCT findings of 100 patients (54 men, 46 women; average age, 54 years) who according to the results of chest radiography had pulmonary tuberculosis of undetermined activity. We assessed HRCT findings such as the presence of a entrilobular, macro-, or micronodule; consolidation, ground-glass opacity, cavity, interlobular septal thickening, irregular linear opacities, bronchial wall thickening, bronchovascular bundle distortion, bronchiectasis, atelectasis, and pericicatrical emphysema. We compared the ratio of the area of nodule and consolidation to that of whole lung, and compared the findings between active and inactive tuberculosis. RESULTS: Eleven of 100 patients were excluded because the final diagnosis was other than tuberculosis. In 59 patients, the presence of active pulmonary tuberculosis was proven by positive sputum smear and/or culture for Mycobacterium tuberculosis. On the basis of the negative results of these tests, pulmonary tuberculosis was found to be inactive in 30 patients; serial chest radiographs indicated that their condition remained stable over a 6-month period. For HRCT, sensitivity was 96.6%, specificity 56.7%, positive predictive value 81.4%, negative predictive value 89.5%, and accuracy 83.1%. For active tuberculosis, the presence of centrilobular nodules, tree-in-bud, macronodules, cavity within the nodule, and consolidations was statistically significant, while for inactive tuberculosis, that of irregular linear opacities, micronodules, bronchiectasis, and cicatrization atelectasis was similarly significant. The CT score for the area of nodules and consolidations was higher in active than in inactive tuberculosis, but only the nodule score showed statistical significance. CONCLUSION: HRCT can be a useful diagnostic tool for evaluating the activity of pulmonary tuberculosis