Search PubMed⌕ Search

Biomedical subjects

Alfredo Chetta

Publications and source records attributed to Alfredo Chetta.

26 records · Page 2Linked to original sources

[Chronic hypersensitivity pneumonitis or idiopathic pulmonary fibrosis? Diagnostic role of high resolution Computed Tomography (HRCT)].

PURPOSE: In the diagnosis of extrinsic allergic alveolitis, high-resolution computed tomography (HRCT) is more sensitive and more specific than radiography; however, the accuracy of HRCT is not absolute. The role of HRCT in this field has scarcely been investigated in the literature. The purpose of this paper is to explore the possibilities of HRCT in this field and to analyse the correlations between HRCT and functional parameters. MATERIALS AND METHODS: We performed a retrospective blind evaluation the HRCT scans of 24 patients (19 males and 5 females). Twelve were affected by idiopathic pulmonary fibrosis (IPF); 12 had chronic extrinsic allergic alveolitis (EAA) or hypersensitivity pneumonitis. The HRCT findings were studied by two radiologists, who were not aware of the diagnoses. The possible differences in evaluation were subsequently resolved by consensus. In the presence of interstitial fibrosis, we recorded the prevailing site and the anatomical extension (with the method of the visual percentage score, described in the literature). In all the cases, we recorded the blood gas values (PaO2, PaCO2, and pH), total lung capacity (TLC), forced expiratory volume in 1 second (FEV1), Vital Capacity (VC), Tiffeneau index (FEV1/VC) and monoxide carbon diffusion (DLCO). The statistical significance of the correlations was investigated using the Mann-Whitney and Wilcoxon tests. Student "t"-test and Pearson's chi squared were used to compare the variables of the different groups. A value of p< or =0.05 was considered significant. RESULTS: Overall, the diagnosis was formulated with a high degree of confidence in 13 of 24 cases (54.1%); in these patients, the result was correct in 84.6% of cases (11 of 13). In the diagnosis of EAA, HRCT sensitivity was 50%, with 91.6% specificity, 70.8% accuracy. In the diagnosis of IPF, HRCT sensitivity was 75%, with 83.3% specificity, 79.1% accuracy. The HRCT signs of interstitial fibrosis were visible in 11 cases of IPF (91.6%) and in 4 cases of EAA (33.3%), with significant statistical difference (p<0.005). In the analysis of the whole series (24 patients) we found a significant inverse correlation between the HRCT score of fibrosis and the extension of the areas with air-trapping (p<0.003). There was no significant difference between IPF and EAA considering age, FEV1, PaO2, PaCO2 and pH. We found inverse correlation (p<0.001) between HRCT extension of the fibrosis and DLCO. There was a significant difference between pulmonary fibrosis and extrinsic allergic alveolitis considering TLC (in average, respectively: 65% and 84.3%; p<0.02), and DLCO (respectively 40.4% and 74.7%; p<0.03). DISCUSSION AND CONCLUSIONS: HRCT is a reliable and strong method to be used in particularly complex fields. We found signs of interstitial fibrosis more frequently in IPF than in EAA (91.6% versus 33.3%). In IPF cases, the extension of the fibrosis--evaluated with the visual score method--was higher then in EAA (34.7% versus 6%). The presence of fibrosis with basal and peripheral distribution was characteristic of idiopathic pulmonary fibrosis, with good sensitivity and specificity (75%), whereas in chronic extrinsic allergic alveolitis the areas of fibrosis often presented an irregular and heterogeneous distribution, in 91.6% of cases. However, 25% of extrinsic allergic alveolitis cases had a distribution mimicking idiopathic pulmonary fibrosis. The presence of areas with increased ground-glass opacity is more common in EAA than in IPF (66.6% versus 33.3%). Areas of mosaic attenuation, visible in inspiratory CT scans, are not rare in IPF (41.6% of cases), and generally have a basal distribution. The presence of hyperlucent lobules inside the fibrotic areas does not exclude the diagnosis of IPF. The finding of the expiratory air-trapping is more common in chronic EAA than in IPF, and the extension of this areas is greater in EAA (17.3% versus 6.5%). We found an inverse correlation between the extension of the fibrosis and the expiratory trapping. Signs of emphysema were observed in 25% of cases, wiema were observed in 25% of cases, with equal prevalence and the same extension in IPF and in EAA. All patients were smokers or ex-smokers. Smoking has not been demonstrated to have a protective effect against EAA. The areas of mosaic perfusion during inspiration do not represent a sound criterion for the differential diagnosis between IPF and chronic EAA. In fact, they can also be frequently found in IPF. HRCT can be employed in clinical practice for the differential diagnosis between IPF and chronic EAA with good (but not absolute) accuracy.

Alveolitis, Extrinsic Allergic↗

Inhaled steroids and airway remodelling in asthma.

Bronchial asthma is a chronic inflammatory disease characterized by inflammatory cell infiltration and by some long-lasting structural changes of bronchial wall, defined as airway remodelling. Airway remodelling can significantly affect two important functional characteristics of asthma, i.e. airway hyperresponsiveness and bronchial obstruction reversibility. Airway remodelling might be responsible for most of the inter-individual variability of bronchial hyperresponsiveness and might also determine the irreversible component of the airway obstruction, sometimes detectable in asthmatic patients. Among anti-asthma drugs, inhaled steroids are the most effective on inflammation and remodelling of airway wall. Recent evidences indicate that high doses of inhaled corticosteroids can significantly reduce not only inflammatory cells but also some components of airway remodelling, such as the increased airway wall vascularity and the basement membrane thickness. Conversely, low doses of inhaled corticosteroids can significantly act only on airway cell infiltration.

Administration, Inhalation↗

Vascular component of airway remodeling in asthma is reduced by high dose of fluticasone.

We conducted a randomized, double-blind, parallel-group study to assess the effect of 6 weeks treatment with low-dose (100 microg twice a day) or high-dose (500 microg twice a day) inhaled fluticasone propionate (FP) on the vascular component of airway remodeling in 30 patients with mild to moderate asthma. We also studied the effect on the inflammatory cells and the basement membrane thickness, and we compared findings from bronchial biopsies taken in patients with asthma with those in eight control subjects. Bronchial responsiveness to methacholine and asthma symptom score were measured before and after treatments. Eight patients in the low-dose FP group and eight patients in high-dose FP group completed the study. At baseline, patients with asthma showed an increase in the number of vessels and in vascular area as compared with control subjects. In the subjects with asthma, number of vessels correlated with vascular area (p < 0.01) and with number of mast cells (p < 0.01). Bronchial responsiveness to methacholine, asthma symptom score, and inflammatory cells decreased significantly after both low- and high-dose FP (p < 0.05). However, the number of vessels, the vascular area, and the basement membrane thickness decreased only after high-dose FP (p < 0.05). In conclusion, this study shows that in patients with mild to moderate asthma, high dose of inhaled FP given over 6 weeks can significantly affect airway remodeling by reducing both submucosal vascularity and basement membrane thickness.

Administration, Inhalation↗

Reliability of quantitative computed tomography to predict postoperative lung function in patients with chronic obstructive pulmonary disease having a lobectomy.

OBJECTIVE: To verify the reliability of quantitative computed tomography (CT) to estimate the postoperative lung function in patients with mild to severe chronic obstructive pulmonary disease (COPD) who underwent a lobectomy. METHODS: Nine COPD patients with lung cancer having a lung lobectomy with preoperative CT were enrolled. By applying a density mask technique and a specific equation, predicted postoperative forced expiratory volume in 1 second (FEV1) and vital capacity (VC) were calculated. Predicted values were correlated with postoperative measured values. RESULTS: Estimated FEV1 and VC were always significantly lower than the corresponding postoperative values; however, CT-estimated postresection FEV1 values were better than the postresection VC values (biases between estimated and measured values were -0.14 and -0.536 L, respectively, according to the Bland-Altman method). Quantitative CT predicted postoperative FEV1 (r = 0.97, P < 0.001) and VC (r = 0.93, P < 0.001) well in all patients, however. CONCLUSIONS: Quantitative CT may be an alternative tool to perfusion scan to predict postresection lung function, even in patients with borderline pulmonary function undergoing a lobectomy.

Aged↗

Pulmonary function testing in interstitial lung diseases.

Interstitial lung diseases (ILDs) are functionally characterized by a restrictive ventilatory defect due to a reduced distensibility of the lung parenchyma. ILD patients also show a reduced exercise tolerance, the main factors limiting exercise capacity being ventilatory and gas exchange abnormalities. Functional abnormalities in ILDs are typical, but not specific. Despite the fact that different lung function patterns have been described among ILDs, they overlap and their practical application to differentiate ILDs is poor. Resting pulmonary function and exercise-induced hypoxemia can aid in defining the prognosis of ILDs and in referring patients for lung transplantation. Additionally, spirometry and diffusing capacity are useful to monitor the response of patients to therapy.

Humans↗

Psychological implications of respiratory health and disease.

The possibility that a subject's psychological status may influence respiratory sensations and that chronic respiratory disease may have psychological consequences has sparked great interest among clinicians and researchers. This paper reviews the existing research on the association between respiratory symptom perception and the psychological status and between chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease, and psychological disturbances. Moreover, it focuses on the role of stressful events in determining asthma exacerbations. The recent literature suggests that in patients with chronic respiratory diseases, the evaluation of breathlessness perception, psychological disturbances and the recording of any stressful events should be considered as relevant as the physical and functional assessment of respiration.

Chronic Disease↗