Gastro-oesophageal reflux and interstitial lung disease.

BACKGROUND: Interstitial lung disease is a heterogeneous entity, which encompasses a large number of pulmonary disorders, including idiopathic pulmonary fibrosis. Gastro-oesophageal reflux appears to be more prevalent in idiopathic pulmonary fibrosis than in controls and in patients with secondary pulmonary fibrosis, but its contribution to interstitial lung disease remains unsettled. AIMS: To prospectively evaluate gastro-oesophageal reflux in patients with interstitial lung disease and to define acid reflux patterns in patients with idiopathic and secondary forms of pulmonary fibrosis. MATERIALS AND METHODS: Twenty-eight patients (15M, median age 66 years, interquartile range 60-71) were studied by history taking, pulmonary function tests, high resolution computed tomography, oesophageal manometry and 24h oesophago-gastric pH monitoring. RESULTS: Sixteen patients (57%) had typical reflux symptoms. All patients completed 24h pH metry and 14 underwent oesophageal manometry. An abnormal oesophageal acid exposure was observed in 19 patients (68%), 13 of which complained of predominant typical reflux symptoms. A diagnosis of idiopathic pulmonary fibrosis was made in 18 patients, while the remaining 10 patients were classified as secondary pulmonary fibrosis. Secondary pulmonary fibrosis patients had more restrictive lung defect, as expressed as Tiffeneau index (p<0.05) and greater acid reflux at nighttime (p<0.05) than idiopathic pulmonary fibrosis patients. CONCLUSIONS: The prevalence of abnormal acid reflux in interstitial lung disease patients is high and, in particular, patients with secondary pulmonary fibrosis show higher oesophageal acid exposure than those with idiopathic form.

Spiral CT evaluation of pulmonary emphysema using a low-dose technique.

PURPOSE: To evaluate the diagnostic accuracy and clinical acceptability of low-dose spiral CT for determining pulmonary volumes and emphysema extension in patients with pulmonary emphysema, in comparison with studies based on spiral CT at conventional dose. MATERIALS AND METHODS: We prospectively evaluated eighteen patients, current or former smokers, with a clinical diagnosis of chronic obstructive pulmonary disease. All the patients underwent: HRCT with three scans at predetermined levels; quantitative spiral CT, with two inspiratory scans, one conventional scan at 240 mA, and the second one a low-dose scan at 80 mA. We used the following parameters: 120 kV, rotation time 0.8", scan time less than 20" (single inspiratory breath-hold), layer thickness 7.5 mm, pitch 6 (high speed), interpolation algorithm at 180 degrees. A 3D reconstruction was performed, with segmentation of the lungs and automatic quantification of pulmonary volumes. We compared the volumes of absolute and percent emphysema and the ratings of the dose delivered to the patient (CTDIw and DLP) obtained with the two spiral CT scans with each other and with the respiratory function tests. RESULTS: The average total lung capacity (TLC) obtained by conventional-dose spiral CT (CTs1) was 6889.4 cc (SD +/-1813.2), and the capacity with low-dose spiral CT (CTs2) was 6929.4 cc (SD +/-1811.6). The percentage of emphysema was 39.7% (range: 2.2-63.5%; SD: +/-19.9) for the CTs1 and 41.1% (range: 2.1-66.4%; SD: +/-20). The CTDIw corresponding to CTs1 was 12.2 mGy (range: 11.9-16.4; SD: +/-1), the one corresponding to CTs2, 3.6 mGy (range: 3.6-4.9; SD: +/-0.3). The DLP corresponding to CTs1 was 391.7 mGy x cm (range: 333.3-518.9; SD: +/-46.7), the one corresponding to CTs2 was 117.8 mGy x cm (range: 100.3-156; SD: +/-14). As for the respiratory function tests, the total lung capacity (TLC) obtained by body plethysmography was 7061 cc (SD: +/-2029.7); the percent TLC was 115.9 (range: 66-165; SD: +/-27.6), the forced expiratory volume at one second (FEV1%, percentage of predicted value) was 46.7% (range: 17-123; SD: +/-27.3), residual volume (RV%) as a percentage of predicted value was 186.3 (range: 84-359; SD: +/-80.7), the Tiffeneau index (TI) was 46% (range: 25-71; SD: +/-15.7). We observed a very significant correlation between radiological and functional TLC for both CT methods. The percentage scores for emphysema obtained with the two methods correlated significantly with the functional indexes. The pixel index of CTs1 correlated with TLC% (r=0.87; p<0.0001), FEV1% (r=-0.53; p<0.02), RV% (r=0.76; p=0.004), TI (r=-0.79; p=0.0001). The pixel index of CTs2 correlated with TLC% (r=0.87; p<0.0001), FEV1% (r=-0.56; p=0.01), RV% (r=0.78; p=0.003), TI (r=-0.8; p=0.0001). The adoption of the method with low tube current entailed a highly significant reduction in the estimated dose delivered to patients (CTDIw and DLP) with r=0.9 and p < 0.0001. DISCUSSION AND CONCLUSIONS: Quantitative low-dose spiral CT is a very good method to quantify pulmonary volumes and calculate the extension of the anatomic emphysema. The reduction of mA from 240 to 80 lowers the estimated dose by 30%, without compromising the accuracy of the results. Our study achieved a highly significant correlation between the results obtained with the two spiral CT techniques and between these results and the respiratory function tests. In clinical practice, the easiest way to reduce the dose in spiral CT of the lung is to reduce the tube current. The low-dose method allows a significant reduction in radiation exposure. Further studies are required to establish to what extent the dose can be reduced without increasing in quantum noise and thereby compromising the quality of the study.

[Longitudinal follow-up evaluation of pulmonary emphysema using high-resolution Computed Tomography (HRCT) study and pulmonary function tests]. / Valutazione evolutiva dell'enfisema polmonare. Correlazioni fra lo studio con tomografia computerizzata con elevata risoluzione (HRCt) e i test funzionali.

PURPOSE: To evaluate the usefulness of HRCT in the identification of longitudinal progression of emphysema and to establish the sensitivity of HRCT compared with functional tests. MATERIAL AND METHODS: 15 ex-smokers with chronic obstructive lung disease were studied, using two consecutive HRCT examinations (t1 and t2); emphysema was evaluated by HRCT visual score and, at the same time, pulmonary function tests. RESULTS: As a whole, the extension of emphysema with HRCT presented a good correlation with Tiffeneau index (IT). At t1 a significant correlation between HRCT and IT was almost reached; it was achieved between HRCT and PaCO2, FEV1 and IT. At t2, there was a significant correlation between HRCT and IT, FEV1 and IT, FEV1 and PaO2, FEV1 and PaCO2, IT and PaO2. In the interval between t1 and t2 there was a significant worsening of HRCT visual score and IT, with no modification of FEV1, PaO2 and PaCO2. The change in HRCT visual score had a significant correlation with FEV1. DISCUSSION AND CONCLUSIONS: HRCT is able not only to identify and quantify anatomic emphysema, but also to evaluate progression of the disease. In the middle-short term anatomic emphysema worsens significantly and visual score HRCT is more sensitive than functional tests for longitudinal evaluation because emphysematous destruction is faster than decline in function. Furthermore emphysematous destruction in smokers progresses even after smoking cessation. The usefulness of combining HRCT with functional tests in the follow-up remains to be established. Longitudinal examination by HRCT could allow us to identify the smokers that tend to develop earlier and more seriously the symptoms of chronic obstructive lung disease.

[Automatic evaluation of total lung capacity and of emphysema involvement with spiral computerized tomography (CT) in obstructive pneumonia]. / Valutazione automatica della capacità polmonare totale e dell'estensione dell'enfisema mediante Tomografia Computerizzata (TC) spirale nella pneumopatia ostruttiva.

OBJECTIVE: To evaluate, in patients with chronic obstructive lung disease or chronic bronchitis, inspiratory helical CT with 3D postprocessing, to measure lung volumes and the amount of emphysema and to compare these measurements with lung function tests. MATERIAL AND METHODS: Seventeen patients with chronic obstructive lung disease disease or chronic bronchitis underwent pulmonary function tests and helical CT after a full inspiration with 3D postprocessing (lower threshold -1024 HU, upper thresholds -200, -300 and -400 HU). Lung inspiratory volumes (TLC-CT) were determined for each model; the amount of emphysema was evaluated by means of an automatic score and a visual score with HRCT. RESULTS: There is a good correlation between automatic and visual scores (p < 0.001); the automatic score had a good correlation with lung function tests, above all with total lung capacity (r = -0.56; p = 0.01) but the visual score had a much closer correlation with DLCO (r = -0.70; p < 0.001). TLC-CT had a significant correlation with pletismographic TLC (TLC-P); the upper threshold -200 HU was more correct (TLC-P = 8011 cc.; TLC-CT 200 = 7138 cc.; r = 0.83; p < 0.001). The volume change of 3D model was about 230 cc. per 100 HU (p < 0.001) modifying upper thresholds, but no change was observed in the volume occupied by emphysema and the percentage of emphysema presented minimal, clinically non significant modifications. DISCUSSION AND CONCLUSIONS: In emphysematous patients, the helical CT with 3D model construction is a good technique to evaluate lung volumes and to quantify emphysema with automatic score; this one, however, probably underscores the extent of pathology; therefore, the addition of a visual score with HRCT is probably worthwhile.

[Role of emphysema in the etiology of functional impairment in patients with severe chronic obstructive pulmonary disease. Study with high resolution computerized tomography]. / Contributo dell'enfisema alla genesi del danno funzionale nei pazienti con grave broncopneumopatia cronica ostruttiva. Studio con Tomografia Computerizzata con elevata risoluzione.

PURPOSE: To investigate whether high-resolution CT (HRCT) can detect the subjects with massive emphysematous destruction in a group of patients with severe chronic obstructive pulmonary disease (COPD) and therefore be of help in selecting the candidates to surgical lung volume reduction. MATERIAL AND METHODS: We examined 40 former smokers with severe COPD (FEV1, < or = 40% of the predicted value, with no major improvement after inhalation of bronchodilators). Clinico-functional assessment included: a flow/volume loop (mean FEV1 = 28.6% of predicted), arterial blood gas analysis at rest breathing room air (mean values: PaO2 = 65.2 mmHg, PaCO2 = 47.4 mmHg), hematocrit value (mean: 45.2%) and the body mass index (mean value: 23.8). The patients were divided into two groups, namely bronchitic (21) and dyspneic (19) subjects, according to onset symptoms. All the patients underwent HRCT with evaluation of emphysema presence, type, site and extent: centrilobular emphysema was seen in 11 cases, panlobular emphysema in 3 and mixed emphysema in 26 cases; the site was superior in 75%, inferior in 7.5% and diffuse in 17.5% of cases; the mean visual score was 40.8%. The presence, type, site and severity of airways disease were also studied, as well as the pathologic dilatation of the pulmonary artery. The patients were divided into three groups (mild, moderate, severe) according to emphysema extent and they were considered to have bronchial disease in the presence of at least 2 of the 6 signs of bronchial involvement. RESULTS: The emphysema extent score was significantly correlated with the hematocrit value and Tiffeneau index (p < .2) in all the 40 patients. The severity of bronchial obstruction was the same in bronchitic and dyspneic patients. The subjects with chronic bronchitis had milder emphysema (mean extent 35% versus 47% in the dyspneic subjects) and a higher frequency of bronchial involvement. A decrease in FEV1 was significantly correlated with emphysema extent (p < .1) in dyspneic, but not in bronchitic, patients. Moreover, the former had better arterial blood gas and lower hematocrit values. CONCLUSIONS: HRCT is a useful tool in diagnosing the presence of emphysema in vivo and in assessing its extent in COPD patients because it permits to divide the patients into two groups which roughly correspond to the clinical patterns of types A (dyspneic) and B (bronchitic). Severe emphysema patients are the best candidates to surgical lung volume reduction. Airways involvement might play a major role in causing bronchial obstruction in the subjects with mild emphysema. In our series HRCT did assess the severity of emphysema in COPD subjects, but our lung function screening failed to predict emphysema extent.

[Idiopathic interstitial pneumonitis presenting with Wells grade III. Can imaging methods help predict further progression of disease?]. / Fibrosi polmonare idiopatica con grado III di Wells all'esordio. Possono le metodiche di diagnostica per immagini aiutare a predire la progressione ulteriore della malattia?

PURPOSE: Three different grades of idiopathic pulmonary fibrosis can be identified by HRCT pattern. Patients with predominant ground-glass opacity (grade I) usually improve after treatment and may have a better prognosis. The subjects with a predominant reticular pattern and honeycombing (grade III) have irreversible fibrosis and usually do not improve after immunosuppressive therapy. Nevertheless, these patients may worsen even in the absence of HRCT features of the so-called alveolitis. We investigated the predictive role of some noninvasive imaging methods (HRCT with visual score of disease extent; Gallium scintigraphy; DTPA scintigraphy) in patients with idiopathic fibrosis and a prevalent macroscopic fibrosis at HRCT study. MATERIAL AND METHODS: Fourteen former smokers with grade III idiopathic fibrosis were examined. None of the patients had been treated. They were all submitted to HRCT, lung function studies, Gallium and DTPA scintigraphy, both at presentation (T0) and follow-up sessions (T1: mean one year post-diagnosis). The HRCT extent of disease was evaluated by means of the visual score as the fraction of the total lung volume. The patients were divided into two groups, using a cut-off value of 50%. All the patients underwent a Gallium scintiscan (using a fixation index of 160 as cut-off) and a ventilatory scintigraphy with DTPA-aerosol, with radionuclide clearance assessment. The lung function tests considered were vital capacity (VC), arterial blood oxygen partial pressure (PaO2) and the diffusing lung capacity for carbon monoxide (DLCO). RESULTS: After one year of follow-up, the HRCT extent score increased (from 46.6% to 50%) and lung function worsened (VC from 66.8% to 63.4% of predicted; DLCO from 37.6% to 27.1%; PaO2 from 77 to 71 mmHg). The patients presenting with HRCT extension score > 50% had a worse lung function at T0 and showed a significant deterioration of PaO2 and HRCT at T1. On the other hand, VC and DLCO significantly worsened in the subjects with HRCT score < 50% at presentation. The patients with a Gallium fixation index > 160 significantly deteriorated in HRCT score, VC and DLCO. Those with Gallium index < 160 had major worsening only for diffusing lung capacity for carbon monoxide. Thirteen of 14 patients had an abnormal value of DTPA clearance at presentation. No variation was observed at T1. DISCUSSION AND CONCLUSIONS: The majority of patients with idiopathic fibrosis are grade III at presentation. They can further deteriorate both in HRCT extent of disease and lung function impairment. After one year of follow-up HRCT extent score increased in 64% of the patients, with a mean increase of 5%. HRCT worsening was more apparent in the patients with a HRCT score > 50% at presentation. In the remaining patients, the worsening of lung function tests was more apparent than the anatomoradiological changes. DTPA clearance had no predictive value in this series. Gallium scintigraphy was a useful prognostic index. The patients with Gallium fixation index > 160 had better lung function and lower HRCT extent score at T0 but significantly deteriorated at T1. A positive Gallium scan at presentation could be considered a useful index of persisting active "alveolitis" in patients with grade III disease, not visible at HRCT study, due to overwhelming fibrosis. These patients, who were untreated, exhibit quicker radiological and functional worsening.

[Quantitative assessment of pulmonary emphysema with computerized tomography. Comparison of the visual score and high resolution computerized tomography, expiratory density mask with spiral computerized tomography and respiratory function tests]. / Valutazione quantitativa dell'enfisema polmonare mediante tomografia computerizzata. Confronto tra il punteggio visivo con alta risoluzione nell'inspirazione, maschera della densità automatica con Tomografia Computerizzata spirale nell'espirazione ed esami funzionali respiratori.

CT is the most accurate method to detect pulmonary emphysema in vivo. We compared prospectively two different methods for emphysema quantitation in 5 normal volunteers and 20 consecutive patients with chronic obstructive pulmonary disease (COPD). All subjects were submitted to function tests and HRCT; three scans were acquired at preselected levels during inspiration. The type and extent of pulmonary emphysema were defined, using the time-honored visual score system, by two independent observers under blind conditions. Disagreements were subsequently settled by consent. All subjects were also examined with expiratory spiral CT, using a density mask program, at two different cut-off levels (-850, -900 HU). Visual score and expiratory spiral density mask values (-850 HU) were significantly correlated (r = 0.86), but the visual extent of emphysema was always higher than shown by expiratory spiral CT. The emphysema extent assessed with both CT methods correlated with the function result of expiratory airflow obstruction and gas diffusion impairment (visual score versus forced expiratory volume in one second: r = -0.81, versus single breath carbon monoxide diffusion: r = -0.78. Spiral expiratory density mask -850 HU versus forced expiratory volume in one second: r = -0.85, versus single breath carbon monoxide diffusion: r = -0.77). When -900 HU was used as the cut-off value for the expiratory density mask, the correlation with single breath carbon monoxide diffusion worsened (r = -0.56). Visual score and expiratory density mask -850 HU gave similar results and permitted COPD patients to be clearly distinguished from normal controls (p < 0.01). Residual lung volume, measured with expiratory spiral CT correlated significantly with residual volume measured with the helium dilution technique (r = 0.66), but CT values were always higher than function results. We believe the true residual volume should lie somewhere in between the CT value and the function results with the helium dilution technique and conclude that the extent of pulmonary emphysema can be confidently assessed with CT methods. Finally, the simple visual score may be as reliable as such highly sophisticated new methods as the spiral expiratory density mask. Expiratory studies offer new insights into different normal and abnormal features of COPD and respiratory impairment.

[The assessment of the activity of idiopathic pulmonary fibrosis by high-resolution computed tomography]. / Valutazione di attività della fibrosi idiopatica polmonare mediante Tomografia Computerizzata ad alta risoluzione.

The authors report the results of the study performed with high resolution CT (HRCT) in a group of 29 patients affected with idiopathic pulmonary fibrosis (IPF). Each patient underwent HRCT at the beginning of the study and after one year. A complete clinico-functional assessment was available in 20 cases and functional CT correlation was made in these patients; 15/20 subjects underwent immunosuppressive therapy with corticosteroids and cyclophosphamide. Disease severity was assessed with chest radiography and HRCT. On the basis of CT findings the patients were classified into three groups, according to Wells classification: predominant ground-glass pattern, mixed pattern and predominant reticular disease with honeycombing. Furthermore, a visual score was assigned to total disease extent and a different score to ground-glass and reticular opacities. Our data confirm the poor accuracy of chest radiography in assessing disease type and overall severity, versus the outstanding diagnostic accuracy of HRCT. We also found a high incidence of mediastinal adenopathies (37.9% of the patients) and signs of pulmonary arterial hypertension (62%), together with low extent of pulmonary emphysema (65.5% of the patients; mean extent: 5.4%). Ground-glass attenuation is an early sign of IPF and might suggest alveolitis activity. In our series, however, the patients with grade I disease were rare (6.8%), but likely to benefit from therapy. Different from Wells, we found no significant difference in the evolution of the patients with grade II versus grade III disease. Wells grading was useful in early disease assessment, but the visual score of total disease extent and the score of ground-glass and reticular opacities were much more useful in the follow-up because they can assess disease progression. Furthermore, in the few patients with predominant alveolitis, who improve after therapy, the relative prevalence of the reticular pattern might allocate the patient in a higher Wells group with a "paradoxical" worsening, if the visual score of the extent of the primary lesion is not used.

Severity scores in respiratory intensive care: APACHE II predicted mortality better than SAPS II.

BACKGROUND: In recent years several scoring systems have been developed to describe the severity of illness, to establish the individual prognosis, and to group adult ICU patients by predicted risk of mortality. In addition, these scores can be used to measure and/or compare the quality of care in different ICUs. We compared the mortality predictions of the Acute Physiology and Chronic Health Evaluation (APACHE II) score and a new Simplified Acute Physiology Score (SAPS II) in patients with respiratory disease who require intensive care. PATIENTS & METHODS: We prospectively studied all 306 admissions from January 1, 1992 through December 31, 1994. McNemar and Hosmer-Lemeshow tests, and receiver operating characteristic (ROC) curves were used to describe and analyze our data. RESULTS: The average APACHE II score was 17.5 (SD 6.0), corresponding to a mean predicted death rate of 24.9% (SD 17.2%) as compared to an observed overall RICU mortality rate of 21.6%. The average SAPS II score was 39.1 (SD 11.1) corresponding to a mean predicted death rate of 26.0% (SD 18.4%). The ratio between the actual and predicted hospital mortality was 86% for APACHE II and 83% for SAPS II. Survivors had a significantly lower predicted risk of death than nonsurvivors (p < 0.0001) with both indices, and a higher Glasgow coma scale score (p < 0.0001). The ROC-curve analysis suggested the superior predictive ability of APACHE II in our patients. Area under the APACHE II ROC curve was 80.88% (standard error [SE] 2.89%), significantly larger (p < 0.01) than that found for SAPS II (73.52%, SE 3.61%). CONCLUSIONS: The APACHE II score was a good predictor of hospital outcome and better than SAPS II in our population.