Two cases of the Marfan syndrome presented with spontaneous pneumothorax. Both had chest radiographs showing bilateral bullae in the upper lung zones and pulmonary function tests consistent with mild emphysema. There were dereases in forced expiratory flow rates at low lung volumes, carbon monoxide transfer factor, and lung elastic recoil. It is suggested that pneumothorax and bullous emphysema in this syndrome are caused by a weakness in the pulmonary connective tissue framework. (+info)
Detection of anti-cytokeratin 8 antibody in the serum of patients with cryptogenic fibrosing alveolitis and pulmonary fibrosis associated with collagen vascular disorders.
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BACKGROUND: It has been suggested that the humoral immune system plays a role in the pathogenesis of cryptogenic fibrosing alveolitis (CFA). Although circulating autoantibodies to lung protein(s) have been suggested, none of the lung proteins have been characterised. The purpose of this study was to determine the antigen to which the serum from patients with pulmonary fibrosis reacted. METHODS: The anti-A549 cell antibody was characterised in a patient with CFA using Western immunoblotting and immunohistochemical staining of A549 cells. As we identified that one of the antibodies against A549 cells was anti-cytokeratin 8, the expression of mRNA of cytokeratin 8 in A549 cells was evaluated. In addition, we attempted to establish an enzyme linked immunosorbent assay to measure the levels of anti-cytokeratin 8 antibody in the serum of patients with CFA and pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). RESULTS: Initially two anti-A549 cell antibodies were detected in the serum of patients with pulmonary fibrosis, one of which was characterised as anticytokeratin 8 antibody by Western immunoblotting. We were able to establish an ELISA to measure anti-cytokeratin 8 antibody and found significantly higher levels in patients with CFA and PF-CVD than in normal volunteers, patients with sarcoidosis, pneumonia, and pulmonary emphysema. CONCLUSIONS: One of the anti-A549 cell antibodies in the serum of patients with CFA was against cytokeratin 8. The serum levels of anti-cytokeratin 8 antibody were increased in patients with CFA and PF-CVD. These results suggest that anticytokeratin 8 antibody may be involved in the process of lung injury in pulmonary fibrosis. (+info)
Improvements in thoracic movement following lung volume reduction surgery in patients with severe emphysema.
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In twelve patients with severe emphysema who underwent lung volume reduction surgery (LVRS), we assessed the results of dyspnea scale, pulmonary function, 6-minute walk distance (6MD), and thoracic movement prior to and 6 months following LVRS. Postoperatively, forced expiratory volume (FEV1), maximum inspiratory mouth pressures (MIP), maximum expiratory mouth pressures (MEP), maximum voluntary ventilation (MVV), diffusing capacity for carbon monoxide (DLCO), partial pressure of oxygen (PaO2) and 6MD were significantly increased with the decrease in dyspnea scale and lung hyperinflation. Thoracic movement, as assessed by the bilateral lung area ratio of the mid-sagittal dimension of dynamic magnetic resonance imaging (MRI) at full inspiration to that at full expiration, was significantly increased. The improvement in thoracic movement was significantly correlated with the increases in FEV1, MVV, and MIP, and with the decrease in residual volume (RV), and with the improvement in the dyspnea scale. These findings suggest that LVRS is an effective procedure for improving not only the airflow limitation and gas exchange but also the thoracic movement in severe emphysema, and these improvements may contribute to an increase in exercise performance and relief of dyspnea. (+info)
Physiological basis of improvement after lung volume reduction surgery for severe emphysema: where are we?
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Lung volume reduction surgery has become an accepted therapeutic option to relieve the symptoms of selected patients with severe emphysema. In a majority of these patients, it causes objective as well as subjective functional improvement. A proper understanding of the physiological determinants underlying these beneficial effects appears very important in order to better select patients for the procedure that is currently largely carried out on an empirical basis. Lung volume reduction surgery has two distinct effects. Firstly, it causes an increased elastic recoil, which at least partially explains the enhanced maximal expiratory flow. Secondly, it is associated with a reduction of hyperinflation which allows for an increase in global inspiratory muscle strength and in diaphragmatic contribution to tidal volume as well as a decrease in the inspiratory elastic load imposed by the chest wall. Taken together, these effects result in a reduced work of breathing and in an enhanced maximal ventilation which both contribute to the increased exercise capacity and reduced dyspnoea after surgery. The improved lung recoil and the reduced hyperinflation after volume reduction surgery were the primary postulates upon which the usual selection criteria for the procedure were based. It is now likely that these are correct. Nevertheless, some patients do not benefit from lung volume reduction surgery and the current literature does not allow for a refinement of the selection process from a physiological point of view. The exact mechanisms underlying the improvement in lung recoil, lung mechanics, and respiratory muscle function remain incompletely understood. Moreover, the effects of lung volume reduction surgery on gas exchange and pulmonary haemodynamics still need to be more fully investigated. An analysis of the characteristics of patients who do not benefit from the procedure and the development of an animal model for lung volume reduction surgery would probably help address these important issues. (+info)
Subjective differentiation of normal and pathological bronchi on thin-section CT: impact of observer training.
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The effect of observer training on sensitivity, specificity and interobserver agreement in the differentiation between normal and pathological bronchi on computed tomography (CT) was studied. The wall thickness of bronchi with normal walls and with pathologically thickened walls were subjectively scored by three independent observers before and after a training period of 2 weeks. Sensitivity, specificity and interobserver agreement were calculated for reading sessions before and after training. Increase and decrease in agreement after training were determined. There was a statistically significant difference (p=0.001) between objectively measured wall thickness of normal and pathological bronchi, both for reference bronchi and for bronchi used for reading sessions. While training increased interobserver agreement, it had no effect on sensitivity (0.46 versus 0.44 after training) and specificity (0.71 versus 0.72 after training) in detecting pathological bronchi. Increased agreement after training was significantly (p=0.001) more frequent than decreased agreement. There is a discrepancy between the effect of training on interobserver agreement and on sensitivity and specificity in the subjective differentiation between normal and pathological bronchi. Interobserver agreement alone is not a reliable indicator of a beneficial effect of training in the evaluation of this parameter. (+info)
Outcome of asthma: longitudinal changes in lung function.
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Current knowledge about factors determining outcome of asthma is limited, but observations over the last few decades suggest that active asthma has a negative impact on the longitudinal changes in lung function. This review aims to give an overview of the present knowledge concerning longitudinal changes in lung function, including clinical markers for distinctly poor outcome with regard to lung function, in children and adults suffering from asthma. The majority of patients with asthma have a good prognosis. However, some patients with asthma, especially those with more severe disease, are at risk of impaired growth of lung function during childhood, a lower maximally attained level of lung function and excessive decline in lung function in adulthood, which may lead to life-threatening lung function impairment. Clinical markers of poorly controlled airway inflammation appear to have a negative impact on the longitudinal changes in lung function, and disease progression to nonreversible airflow obstruction may be observed in a minority of patients with asthma. Early intervention with anti-inflammatory therapy may improve the short-term outcome of asthma, but long-term controlled studies are clearly needed in order to verify whether or not treatment, especially with inhaled corticosteroids, according to the current international guidelines alters the natural history of asthma, i.e. disease progression with regard to changes in lung function and possible development of nonreversible airflow obstruction. (+info)
Surgical aspects and techniques of lung volume reduction surgery for severe emphysema.
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Lung volume reduction surgery (LVRS) has become an accepted procedure for palliative treatment of diffuse, nonbullous emphysema. Single or multiple peripheral segmental wedge resections of the most destroyed areas of the lungs are performed with the use of stapling devices, in order to decrease hyperinflation and restore diaphragmatic function. Median sternotomy, videoendoscopy or anterior muscle sparing thoracotomies have been used as surgical approaches. The functional improvement after bilateral resections exceed those after a unilateral approach. LVRS has demonstrated its potential as an alternative to transplantation, and with growing experience, the indications for the procedure have been widened. In selected patients with peripheral lung cancer who have been considered unsuitable for a surgical resection, the combination of both tumour resection and LVRS has successfully been performed. In contrast to LVRS, laser surgery of the emphysematous lung has been abandoned in most institutions. (+info)
Emphysematous lesions, inflammation, and fibrosis in the lungs of transgenic mice overexpressing platelet-derived growth factor.
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Because of its expression pattern and its potent effects on mesenchymal cells, platelet-derived growth factor (PDGF) has been implicated as an important factor in epithelial-mesenchymal cell interactions during normal lung development and in the pathogenesis of fibrotic lung disease. To further explore the role of PDGF in these processes, we have developed transgenic mice that express the PDGF-B gene from the lung-specific surfactant protein C (SPC) promoter. Adult SPC-PDGFB transgenic mice exhibited lung pathology characterized by enlarged airspaces, inflammation, and fibrosis. Emphysematous changes frequently occurred throughout the lung, but inflammation and fibrotic lesions were usually confined to focal areas. The severity of this phenotype varied significantly among individual mice within the same SPC-PDGFB transgenic lineage. A pathology similar to that observed in adult mice was noted in lungs from transgenic mice as young as 1 week of age. Neonatal transgenic mice exhibited enlarged saccules and thickened primary septa. Results of these studies indicated that overexpression of PDGF-B induced distinct abnormalities in the developing and adult lung and led to a complex phenotype that encompassed aspects of both emphysema and fibrotic lung disease. (+info)