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PubMed1997

Quantification of idiopathic pulmonary fibrosis using computed tomography and histology.

We used computed tomography (CT) and histologic analysis to quantify lung structure in idiopathic pulmonary fibrosis (IPF). CT scans were obtained from IPF and control patients and lung volumes were estimated from measurements of voxel size, and X-ray attenuation values of each voxel. Quantitative estimates of lung structure were obtained from biopsies obtained from diseased and normal CT regions using stereologic methods. CT density was used to calculate the proportion of tissue and air, and this value was used to correct the biopsy specimens to the level of inflation during the CT scan. The data show that IPF is associated with a reduction in airspace volume with no change in tissue volume or weight compared with control lungs. Lung surface area decreased two-thirds (p < 0.001) and mean parenchymal thickness increased tenfold (p < 0.001). An exudate of fluid and cells was present in the airspace of the diseased lung regions and the number of inflammatory cells, collagen, and proteoglycans was increased per 100 g of tissue in IPF. We conclude that IPF reorganized lung tissue content causing a loss of airspace and surface area without increasing the total lung tissue.

Aged↗
PubMed1997

Functional impairment in lone cryptogenic fibrosing alveolitis and fibrosing alveolitis associated with systemic sclerosis: a comparison.

Lone cryptogenic fibrosing alveolitis (CFA) is histologically identical to fibrosing alveolitis associated with systemic sclerosis (FASSc), but it has a much worse prognosis after matching for disease severity at presentation. Thin-section CT scanning (CT) provides a reproducible method of quantifying the morphologic extent of fibrosing alveolitis. The aim of this study was to gain insights into contrasting pathophysiologic mechanisms in the two diseases by comparing patterns of functional impairment after matching for extent of disease on CT, demographic factors, smoking history, and concurrent treatment. Patients with emphysema on CT (n = 16) and patients with FASSc with overt pulmonary hypertension (n = 5) were excluded; 111 patients were studied (CFA, n = 54; FASSc, n = 57). Patients with CFA were distinguished by more severe functional impairment and more extensive disease on CT (40.1 versus 22.1%, p < 0.00005). On multivariate analysis, patients with CFA had greater reduction in arterial P(O2) (p < 0.0005), wider AaP(O2) (p < 0.0005), greater oxygen desaturation on maximal exercise (p < 0.03), and higher dyspnea scores (p < 0.02) than did patients with FASSc after controlling for extent of disease on CT and other covariates. Measures of lung volume and gas transfer did not differ independently between CFA and FASSc. These findings persisted in subanalyses of patients with limited disease, extensive disease, histologic confirmation of fibrosing alveolitis, and with the reinclusion of patients with emphysema and pulmonary hypertension. The patterns of functional impairment were indicative of more severe ventilation-perfusion mismatch or anatomic shunting in CFA after adjustment for disease extent; we speculate that perfusion of poorly ventilated lung parenchyma in CFA occurs through new vessels formed in areas of intense inflammation. This mechanism may contribute to the greater mortality of patients with CFA than of patients with FASSc because of the deleterious effects of hypoxia on concurrent cardiac disease.

Female↗
PubMed1998

Serum level of interleukin 8 is elevated in idiopathic pulmonary fibrosis and indicates disease activity.

It has been shown that interleukin 8 (IL-8) is increased in bronchoalveolar lavage fluid (BALF) of patients with idiopathic pulmonary fibrosis (IPF) and there is increasing evidence that it is involved in the pathogenesis of this disease. To date, no data are available as to whether IL-8 is elevated in sera of IPF patients. We obtained sera from 42 patients with IPF and 20 healthy controls at time of BAL. From 20 of 42 patients with IPF and 12 of 20 controls BALF was available, enabling us to measure IL-8 in serum and BALF of the same time point. IL-8 was significantly elevated in serum (54.7 +/- 7.5 pg/ml, p < 0.0001) and BALF (715.7 +/- 112.4 pg/ml, p < 0.0001) of patients with IPF compared with controls (IL-8 in serum, 5.2 +/- 0.8 pg/ml; IL-8 in BALF, 67.3 +/- 9.7 pg/ml). We observed a significant positive correlation between IL-8 levels in BALF and percentage of BALF neutrophils (p < 0.001) and between serum IL-8 and BALF IL-8 levels (p < 0.005) in patients with IPF. Consequently, the serum IL-8 level correlated positively with the percentage of BAL neutrophils (p < 0.01), indicating that it may reflect the degree of neutrophilic alveolitis in IPF. Furthermore, the serum IL-8 level showed a negative correlation with important indicators of impairment of lung function (DL(CO), TLC, VC) and PaO2. In conclusion, we were able to demonstrate that the degree of neutrophilic alveolitis in IPF is reflected by increased serum levels of IL-8 and we suggest that the serological assessment of IL-8 may provide a useful parameter for clinicians in monitoring patients with IPF.

Anti-Inflammatory Agents↗
PubMed1998

Idiopathic pulmonary fibrosis: predicting response to therapy and survival.

Idiopathic pulmonary fibrosis (IPF) is associated with significant morbidity and mortality despite aggressive therapy. Thirty-eight patients with biopsy-proven IPF were studied to identify pretreatment features that could be used to predict short-term improvement in pulmonary function and improved longer term survival. In all patients, a pretreatment clinical (dyspnea), radiographic (chest radiograph), and physiologic (pulmonary function including exercise saturation) score was generated (CRP). A high-resolution CT scan (HRCT) was independently scored by four radiologists for ground glass (CT-alv) and linear opacity (CT-fib) on a scale of 0-4. Open lung biopsy samples were scored for cellular infiltration, interstitial fibrosis, desquamation, and granulation by an experienced pulmonary pathologist. All patients were treated with 3 mo of high-dose steroids and the CRP scoring repeated. Patients were divided into three groups: responders with a greater than 10-point drop in CRP (n = 10); stable with +/- 10 point change in CRP (n = 14); and nonresponders with > 10 point rise in CRP or death (n = 14). Those responding to steroids were treated for 18 mo in a tapering fashion. In all others, steroids were tapered quickly and oral cyclophosphamide prescribed. Responders (10 of 38) had a lower age (45.1+/-4.3 yr) than nonresponders (61.4+/-3.5 yr) or those remaining stable (53.1+/-3.3 yr) (p = 0.01). Pretreatment CRP was higher in responders (58.8+/-5.6) than nonresponders (40.5+/-4.7) or stable individuals (37.6+/-4.7) (p = 0.01). Cellular infiltration score of the open lung biopsies was higher in responders (7.6+/-0.6) than stable individuals (5.7+/-0.5) (p = 0.04). The CT-alv scores were higher and CT-fib scores were lower in responders than nonresponders. Receiver operating curve (ROC) analysis was employed to identify pretreatment features of longer term survival (follow-up of 29.1+/-2.3 mo). Only CT-fib (p = 0.009) and pathology fibrosis score (p = 0.03) were able to predict mortality. A pretreatment CT-fib score > or = 2.0 demonstrated 80% sensitivity and 85% specificity in predicting survival. Those patients who did not respond to initial steroid therapy demonstrated a worse long-term survival and greater likelihood of decreased pulmonary function. We demonstrate that pretherapy pulmonary function, pathologic and radiographic parameters are different in individuals who respond to initial prednisone therapy. Only HRCT imaging and pathologic fibrosis were able to reliably predict long-term survival in patients with biopsy-proven IPF.

Adult↗
PubMed1998

Improved exercise performance following lung volume reduction surgery for emphysema.

Lung volume reduction surgery (LVRS) for emphysema has been suggested to improve patient lung function and activity. The short-term impact of LVRS on exercise performance was evaluated using maximal and submaximal steady-state exercise testing in 27 patients with severe hypoxemic chronic obstructive pulmonary disease (COPD), along with measurements of patient function, dyspnea, and quality of life. LVRS significantly improved exercise performance, due to ventilatory improvements associated with increased ventilatory reserve, enhanced tidal volume recruitment, and improved alveolar ventilation. Preoperative measurements of ventilatory reserve and dead space ventilation during exercise testing were closely associated with improved exercise performance. Improvements in patient dyspnea, walk distances, and quality of life also occurred following LVRS and were associated with improvements in exercise performance. Surgical mortality from LVRS was low (4%), but short-term all-cause mortality was increased (19%). Short-term mortality was associated with reduced expiratory muscle strength and markedly elevated dead space ventilation. We conclude that LVRS produces significant improvements in exercise performance, dyspnea, and quality of life in selected patients with COPD. Physiologic prediction of patients most likely to survive for an extended period and have significant benefit following LVRS may also be possible.

Adult↗
PubMed1998

Increased prevalence of gastroesophageal reflux in patients with idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal interstitial lung disease (ILD) of unknown etiology. Introduction of acid into the respiratory tree can produce pulmonary fibrosis. Gastroesophageal reflux (GER) has previously been associated with several other respiratory conditions, including pneumonia, bronchitis, and asthma. To investigate prospectively the possible association of GER and IPF, 17 consecutive patients with biopsy-proven IPF and eight control patients with ILD other than IPF underwent dual-channel, ambulatory esophageal pH monitoring. Sixteen of 17 patients with IPF had abnormal distal and/or proximal esophageal acid exposure compared with four of eight control patients (p = 0.02). In the patients with IPF, mean percent distal total (13.6 versus 3.34, p = 0.006), distal upright (12.4 versus 5.1, p = 0.04), distal supine (14.7 versus 0.88, p = 0.02), and proximal supine (7.48 versus 0.24, p = 0.04) esophageal acid exposure times were significantly greater than those in control patients. Only four patients with IPF (25%) with increased acid exposure had typical reflux symptoms such as heartburn or regurgitation. Patients with IPF have a high prevalence of increased esophageal acid exposure, usually without typical GER symptoms. GER in these patients tends to occur at night and extend into the proximal esophagus. Acid reflux may be a contributing factor in the pathogenesis of IPF.

Adult↗
PubMed1999

Type III and type I procollagen markers in fibrosing alveolitis.

Deposition of types I and III collagen is a typical feature in the development of pulmonary fibrosis. We assessed the propeptides of these procollagens as prognostic markers in 18 patients with fibrosing alveolitis. We analyzed the amino-terminal propeptide of type III procollagen (PIIINP) and the carboxy-terminal propeptide of type I procollagen (PICP) from samples of bronchoalveolar lavage fluid (BALF) and serum, and also estimated their concentrations in epithelial lining fluid (ELF) by the urea method. The level of PIIINP in serum (p < 0.05), BALF (p < 0.05), and ELF (p < 0.05), and the levels of PICP in BALF (p < 0.001) and ELF (p < 0.001) but not in serum, were significantly increased in the patients with fibrosing alveolitis as compared with 17 controls who had been investigated for minor respiratory symptoms. In the BALF and ELF of patients with fibrosing alveolitis, PICP but not PIIINP had significant negative correlations with the specific diffusion coefficient for carbon monoxide (DLCO/ VA). The amino-terminal propeptide of type III procollagen and the carboxy-terminal propeptide of type I procollagen in BALF correlated significantly with one another. During the follow-up period of 6 yr, seven of the 18 patients with fibrosing alveolitis died of the disease, 3 others died of malignancy, and one patient died from an unknown cause. DLCO (p < 0.05) differed significantly between the surviving patients and those who died of fibrosing alveolitis, and detectable PIIINP in BALF predicted death from fibrosing alveolitis (p = 0.05). In conclusion, these results show that PIIINP in BALF, ELF, and serum, and PICP in BALF and ELF, are increased in patients with fibrosing alveolitis. A high level of PICP in BALF, and especially in ELF, suggests a chronic process and increased synthesis of type I collagen in the lungs, whereas PIIINP in BALF and ELF suggests active disease and a poor prognosis.

Biomarkers↗
PubMed1999

A randomized clinical trial of alpha(1)-antitrypsin augmentation therapy.

We have investigated whether restoration of the balance between neutrophil elastase and its inhibitor, alpha(1)-antitrypsin, can prevent the progression of pulmonary emphysema in patients with alpha(1)-antitrypsin deficiency. Twenty-six Danish and 30 Dutch ex-smokers with alpha(1)-antitrypsin deficiency of PI*ZZ phenotype and moderate emphysema (FEV(1) between 30% and 80% of predicted) participated in a double-blind trial of alpha(1)-antitrypsin augmentation therapy. The patients were randomized to either alpha(1)-antitrypsin (250 mg/kg) or albumin (625 mg/kg) infusions at 4-wk intervals for at least 3 yr. Self-administered spirometry performed every morning and evening at home showed no significant difference in decline of FEV(1) between treatment and placebo. Each year, the degree of emphysema was quantified by the 15th percentile point of the lung density histogram derived from computed tomography (CT). The loss of lung tissue measured by CT (mean +/- SEM) was 2.6 +/- 0.41 g/L/yr for placebo as compared with 1.5 +/- 0.41 g/L/yr for alpha(1)-antitrypsin infusion (p = 0.07). Power analysis showed that this protective effect would be significant in a similar trial with 130 patients. This is in contrast to calculations based on annual decline of FEV(1) showing that 550 patients would be needed to show a 50% reduction of annual decline. We conclude that lung density measurements by CT may facilitate future randomized clinical trials of investigational drugs for a disease in which little progress in therapy has been made in the past 30 yr.

Double-Blind Method↗
PubMed2001

Relationship between extent of pulmonary emphysema by high-resolution computed tomography and lung elastic recoil in patients with chronic obstructive pulmonary disease.

We investigated the relationship between the extent of pulmonary emphysema, assessed by quantitative high-resolution computed tomography (HRCT), and lung mechanics in 24 patients with chronic obstructive pulmonary disease (COPD). The extent of emphysema was quantified as the relative lung area with CT numbers < -950 Hounsfield Units (HU). Patients with COPD had severe airflow obstruction (FEV(1) 35 +/- 15% pred) and severe reduction of CO diffusion constant (DCO/VA 37 +/- 19% pred). Maximal static elastic recoil pressure (Pst(max)) averaged 54 +/- 24% predicted, and the exponential constant K of pressure-volume curves was 258 +/- 116% predicted. Relative lung area with CT numbers < -950 HU averaged 21 +/- 11% (range 1 to 38%). It showed a highly significant negative correlation with DCO/VA (r = -0.84, p < 0.0001), a weak correlation with FEV(1)% predicted, and no correlation with either Pst(max) or constant K. A significant relationship was found between the natural logarithm of K and the full width at half maximum of the frequency distribution of CT numbers, taken as an index of the heterogeneity of lung density (r = 0.68, p < 0.0005). We conclude that currently used methods of assessing the extent of emphysema by HRCT closely reflect the reduction of CO diffusion constant, but cannot predict the elastic properties of the lung tissue.

Aged↗
PubMed1990

Alterations in pulmonary function in cancer patients receiving adoptive immunotherapy with tumor-infiltrating lymphocytes and interleukin-2.

Adoptive immunotherapy with tumor-infiltrating lymphocytes (TIL) and interleukin-2 (IL-2) is currently being investigated in the treatment of chemoresistant cancers. In protocols using high dosages of IL-2 and adoptive transfers of lymphokine-activated killer (LAK) cells, severe pulmonary toxicities, including pulmonary edema and respiratory failure, are regularly observed. Serial measurements of pulmonary function in patients receiving TIL and continuous infusions of moderate dosages of IL-2 showed the development of mild obstructive and restrictive defects. Partial reversibility of the FEV1 with bronchodilators was observed, suggesting the development of hyperreactive airways. Decreases in lung volumes, DLCO, and gas exchange occurred and may reflect pulmonary infiltration by inflammatory cells, increased lung water, or diminished chest wall function. We conclude that adoptive immunotherapy with TIL and IL-2 produces changes in systemic immune response that may contribute to abnormal pulmonary physiology.

Combined Modality Therapy↗
PubMed1990

Emphysema in silicosis. A comparison of smokers with nonsmokers using pulmonary function testing and computed tomography.

The presence of emphysema in silicosis is believed to be secondary to the development of progressive massive fibrosis (PMF). However, it is difficult to separate out other causative factors, particularly cigarette smoking. In order to attempt to distinguish these factors, we examined 30 patients with silicosis by means of pulmonary function testing and computed tomography (CT) scans of the chest. Eighteen of these patients were either exsmokers or current smokers, and 12 of them were nonsmokers. The CT scans were read independently by two observers on two separate occasions. Silicosis was graded on a 5-point scale from 0 to 4; emphysema was graded as a percentage of lung involved. Percent emphysema was associated with level of pulmonary function (FEV1, FVC, and DLCO) independent of its association with either cigarette smoking or silicosis grade (p less than 0.01). Silicosis grade was associated with DLCO (p less than 0.05) independent of its association with either cigarette smoking or percent emphysema, but was not associated with level of FEV1 or FVC. In the group without PMF (silicosis Grade 0, 1, or 2), smokers had worse emphysema than nonsmokers (p less than 0.01); there was no such difference among the patients with PMF (silicosis Grade 3 or 4). Only one of the nonsmoking subjects with silicosis but without PMF had any emphysema detected on CT. Our data suggest that silicosis, in the absence of PMF, does not cause significant emphysema, and that it is primarily the degree of emphysema rather than the degree of silicosis that determines the level of pulmonary function.

Adult↗
PubMed1991

Silicosis, chronic airflow limitation, and chronic bronchitis in South African gold miners.

In a cross-sectional study of a working population of black South African gold miners, 1,197 men were studied with respiratory and occupational questionnaires, lung function tests, and chest radiographs. The study was designed to examine the effects of silicosis on respiratory symptoms and lung function. A total of 857 men with chronic, simple silicosis and 340 men without silicosis were included in the sample. Other determinants of lung disease including the duration and intensity of underground dust exposure and tobacco smoking were also examined. Three distinct pulmonary disorders could be discerned: silicosis-associated pulmonary dysfunction with dyspnea on effort; chronic airflow limitation, which was related to the duration of underground exposure; and a chronic bronchitic symptom complex, which reflected the intensity of dust exposure in the workplace. Chronic, uncomplicated silicosis was found to be associated with significant loss of lung function, and all of the measured indices, FVC, FEV1, FEV1/FVC%, maximal midexpiratory flow rate (MMEF), and lung diffusion for carbon monoxide measured by the single-breath method (DLCO) were reduced. When comparing men with Category 3/3 nodule profusion with men without silicosis, reductions of FVC of 351 ml, FEV1 of 447 ml, MMEF of 1.04 L/s, and DLCO of 4.7 ml/min/mm Hg (p = 0.0001) were detected after controlling for age, height, the direct effects of the underground environment, and tobacco smoking. Dyspnea on effort was more common in the men with silicosis (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Pathogenetic significance of reactive oxygen species in diffuse fibrosing alveolitis.

Excessive release of reactive oxygen metabolites (ROM) from lung inflammatory cells has been claimed to be of major pathogenetic significance in diffuse fibrosing alveolitis. In the present study, the content of oxidized methionine residues [Met(O)] as a percentage of total methionine (Met) in BAL-derived proteins was used to assess the biologic effect of ROM. In addition, procollagen-III-peptide was measured in BAL fluid as a marker of fibroblast activation. We investigated bronchoalveolar lavage (BAL) samples from seven control patients without evidence of interstitial lung disease and from 42 patients with fibrosing alveolitis caused by idiopathic pulmonary fibrosis (IPF), n = 20, or by collagen vascular disease (CVD), n = 22. Met(O) was elevated in the patients with IPF or CVD compared with that in the control subjects (8.86 +/- 1.26 and 8.13 +/- 1.44% versus 3.36 +/- 0.49%, p less than 0.01 and p less than 0.05, respectively; mean +/- SEM). A positive correlation was found between percentage of neutrophils in BAL and Met(O) in both groups separately and combined (IPF, r = 0.84; p less than 0.001; CVD, r = 0.44; p less than 0.05; IPF and CVD, r = 0.60; p less than 0.001), whereas an inverse relationship existed between Met(O) and the percentage of alveolar macrophages in BAL (IPF, r = -0.59; p less than 0.01; CVD, r = -0.24; NS; IPF and CVD, r = -0.41; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗