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OBJECTIVE. The clinical management of patients with idiopathic pulmonary fibrosis differs markedl... more OBJECTIVE. The clinical management of patients with idiopathic pulmonary fibrosis differs markedly from that of patients with hypersensitivity pneumonitis. However, the two diseases often cannot be differentiated on clinical grounds. The purpose of this study was to establish whether CT can be used to make the distinction.

It is not known if a surgical lung biopsy is necessary in all patients for the diagnosis of idiop... more It is not known if a surgical lung biopsy is necessary in all patients for the diagnosis of idiopathic pulmonary fibrosis (IPF). We conducted a blinded, prospective study at eight referring centers. Initially, cases were evaluated by clinical history and examination, transbronchial biopsy, and high-resolution lung computed tomography scans. Pulmonologists at the referring centers then assessed their certainty of the diagnosis of IPF and provided an overall diagnosis, before surgical lung biopsy. The lung biopsies were reviewed by a pathology core and 54 of 91 patients received a pathologic diagnosis of IPF. The positive predictive value of a confident (certain) clinical diagnosis of IPF by the referring centers was 80%. The positive predictive value of a confident clinical diagnosis was higher, when the cases were reviewed by a core of pulmonologists (87%) or radiologists (96%). Lung biopsy was most important for diagnosis in those patients with an uncertain diagnosis and those thought unlikely to have IPF. These studies suggest that clinical and radiologic data that result in a confident diagnosis of IPF by an experienced pulmonologist or radiologist are sufficient to obviate the need for a lung biopsy. Lung biopsy is most helpful when clinical and radiologic data result in an uncertain diagnosis or when patients are thought not to have IPF.

Emphysema due to cigarette smoking is characterized by a loss of alveolar structures. We hypothes... more Emphysema due to cigarette smoking is characterized by a loss of alveolar structures. We hypothesize that the disappearance of alveoli involves apoptosis of septal endothelial cells and a decreased expression of lung vascular endothelial growth factor (VEGF) and its receptor 2 (VEGF R2). By terminal transferase dUTP nick end labeling (TUNEL) in combination with immunohistochemistry, we found that the number of TUNEL+ septal epithelial and endothelial cells/lung tissue nucleic acid (microg) was increased in the alveolar septa of emphysema lungs (14.2 +/- 2.0/microg, n = 6) when compared with normal lungs (6.8 +/- 1.3/microg, n = 7) (p < 0.01) and with primary pulmonary hypertensive lungs (2.3 +/- 0.8/microg, n = 5) (p < 0.001). The cell death events were not significantly different between healthy nonsmoker (7.4 +/- 1.9/microg) and smoker (5.7 +/- 0.7/microg) control subjects. The TUNEL results were confirmed by single-stranded DNA and active caspase-3 immunohistochemistry, and by DNA ligation assay. Emphysema lungs (n = 12) had increased levels of oligonucleosomal-length DNA fragmentation when compared with normal lungs (n = 11). VEGF, VEGF R2 protein, and mRNA expression were significantly reduced in emphysema. We propose that epithelial and endothelial alveolar septal death due to a decrease of endothelial cell maintenance factors may be part of the pathogenesis of emphysema.

Journal of Computer Assisted Tomography, 1995

The purposes of this study were to describe and compare the prevalence of disease features in sub... more The purposes of this study were to describe and compare the prevalence of disease features in subjects with Mycobacterium avium complex (MAC) disease with those of Mycobacterium tuberculosis infection (MTB), to compare the abilities of CT and chest radiography to identify the features of MAC disease, and to determine if sputum positivity is related to any of the CT features of MAC disease. Computed tomographic scans of 15 subjects with MTB and 55 subjects with MAC were reviewed by 2 observers. Sputum culture results (obtained within 1.9 +/- 2.8 days of scanning) were available in 50 of the 55 subjects with MAC. Bronchiectasis involving four or more lobes (often associated with centrilobular nodules) was seen only in subjects with MAC. The combination of right middle lobe and lingular bronchiectasis was seen only in MAC (p = 0.015). Thirty-one of the 34 subjects (91%) with MAC who had cavities on CT had a positive sputum culture within 3 weeks of CT, compared with 7 of 12 subjects (58%) without cavities (p = 0.001). Similarly, 36 of 42 subjects (85%) with airspace disease, but only 2 of 8 subjects (25%) without airspace disease grew mycobacteria from their sputa (p < 0.001). Sputum positivity was not associated with the presence of bronchiectasis (p = 0.156) or nodules (p = 0.377). A subgroup of patients with MAC may be distinguished from those with MTB by the presence of widespread bronchiectasis, particularly if it involves the right middle lobe and lingula. Cavities and airspace opacification on CT are associated with positive sputum cultures for MAC.

OBJECTIVE. The clinical management of patients with idiopathic pulmonary fibrosis differs markedl... more OBJECTIVE. The clinical management of patients with idiopathic pulmonary fibrosis differs markedly from that of patients with hypersensitivity pneumonitis. However, the two diseases often cannot be differentiated on clinical grounds. The purpose of this study was to establish whether CT can be used to make the distinction.

It is not known if a surgical lung biopsy is necessary in all patients for the diagnosis of idiop... more It is not known if a surgical lung biopsy is necessary in all patients for the diagnosis of idiopathic pulmonary fibrosis (IPF). We conducted a blinded, prospective study at eight referring centers. Initially, cases were evaluated by clinical history and examination, transbronchial biopsy, and high-resolution lung computed tomography scans. Pulmonologists at the referring centers then assessed their certainty of the diagnosis of IPF and provided an overall diagnosis, before surgical lung biopsy. The lung biopsies were reviewed by a pathology core and 54 of 91 patients received a pathologic diagnosis of IPF. The positive predictive value of a confident (certain) clinical diagnosis of IPF by the referring centers was 80%. The positive predictive value of a confident clinical diagnosis was higher, when the cases were reviewed by a core of pulmonologists (87%) or radiologists (96%). Lung biopsy was most important for diagnosis in those patients with an uncertain diagnosis and those thought unlikely to have IPF. These studies suggest that clinical and radiologic data that result in a confident diagnosis of IPF by an experienced pulmonologist or radiologist are sufficient to obviate the need for a lung biopsy. Lung biopsy is most helpful when clinical and radiologic data result in an uncertain diagnosis or when patients are thought not to have IPF.

Emphysema due to cigarette smoking is characterized by a loss of alveolar structures. We hypothes... more Emphysema due to cigarette smoking is characterized by a loss of alveolar structures. We hypothesize that the disappearance of alveoli involves apoptosis of septal endothelial cells and a decreased expression of lung vascular endothelial growth factor (VEGF) and its receptor 2 (VEGF R2). By terminal transferase dUTP nick end labeling (TUNEL) in combination with immunohistochemistry, we found that the number of TUNEL+ septal epithelial and endothelial cells/lung tissue nucleic acid (microg) was increased in the alveolar septa of emphysema lungs (14.2 +/- 2.0/microg, n = 6) when compared with normal lungs (6.8 +/- 1.3/microg, n = 7) (p < 0.01) and with primary pulmonary hypertensive lungs (2.3 +/- 0.8/microg, n = 5) (p < 0.001). The cell death events were not significantly different between healthy nonsmoker (7.4 +/- 1.9/microg) and smoker (5.7 +/- 0.7/microg) control subjects. The TUNEL results were confirmed by single-stranded DNA and active caspase-3 immunohistochemistry, and by DNA ligation assay. Emphysema lungs (n = 12) had increased levels of oligonucleosomal-length DNA fragmentation when compared with normal lungs (n = 11). VEGF, VEGF R2 protein, and mRNA expression were significantly reduced in emphysema. We propose that epithelial and endothelial alveolar septal death due to a decrease of endothelial cell maintenance factors may be part of the pathogenesis of emphysema.

Journal of Computer Assisted Tomography, 1995

The purposes of this study were to describe and compare the prevalence of disease features in sub... more The purposes of this study were to describe and compare the prevalence of disease features in subjects with Mycobacterium avium complex (MAC) disease with those of Mycobacterium tuberculosis infection (MTB), to compare the abilities of CT and chest radiography to identify the features of MAC disease, and to determine if sputum positivity is related to any of the CT features of MAC disease. Computed tomographic scans of 15 subjects with MTB and 55 subjects with MAC were reviewed by 2 observers. Sputum culture results (obtained within 1.9 +/- 2.8 days of scanning) were available in 50 of the 55 subjects with MAC. Bronchiectasis involving four or more lobes (often associated with centrilobular nodules) was seen only in subjects with MAC. The combination of right middle lobe and lingular bronchiectasis was seen only in MAC (p = 0.015). Thirty-one of the 34 subjects (91%) with MAC who had cavities on CT had a positive sputum culture within 3 weeks of CT, compared with 7 of 12 subjects (58%) without cavities (p = 0.001). Similarly, 36 of 42 subjects (85%) with airspace disease, but only 2 of 8 subjects (25%) without airspace disease grew mycobacteria from their sputa (p < 0.001). Sputum positivity was not associated with the presence of bronchiectasis (p = 0.156) or nodules (p = 0.377). A subgroup of patients with MAC may be distinguished from those with MTB by the presence of widespread bronchiectasis, particularly if it involves the right middle lobe and lingula. Cavities and airspace opacification on CT are associated with positive sputum cultures for MAC.

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