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Thomas V Colby

Publications and source records attributed to Thomas V Colby.

At least 37 records · Page 2Linked to original sources
PubMed2004

Disseminated basidiobolomycosis in an immunocompetent woman.

Basidiobolomycosis is a chronic subcutaneous infection of the trunk and limbs due to Basidiobolus ranarum. The disease is well known in tropical areas, although recent cases of gastrointestinal basidiobolomycosis have also been reported in Arizona. We describe a young immunocompetent women who had presented with eosinophilia and lung infiltrates. She subsequently died, and diagnosis of disseminated basidiobolomycosis was made on the basis of histological features at autopsy.

Adult↗
PubMed2004

CT features of lung disease in patients with systemic sclerosis: comparison with idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia.

PURPOSE: To evaluate computed tomographic (CT) patterns of lung disease in patients with systemic sclerosis (SSc) and compare them with CT appearance in patients with biopsy-proved idiopathic pulmonary fibrosis (IPF) and idiopathic nonspecific interstitial pneumonia (NSIP). MATERIALS AND METHODS: The CT features of consecutive patients with SSc (n = 225; male patients, 44; female patients, 181; median age, 47 years; age range, 16-78 years), IPF (n = 40; men, 26; women, 14; median age, 54.5 years; age range, 36-77 years) and NSIP (n = 27; men, 18; women, nine; median age, 53 years; age range, 32-68 years) were quantified separately by two observers. The extent of interstitial lung disease, ground-glass opacification, emphysema, and the coarseness of a reticular pattern were quantified. Group comparisons were made nonparametrically with the Wilcoxon rank sum test. Differences in CT features were identified with multiple logistic regression analysis. RESULTS: The coarseness of fibrosis was similar in patients with SSc and idiopathic NSIP but strikingly different between patients with SSc (median coarseness score, 5.5; range, 0.0-13.3) and IPF (median coarseness score, 8.8; range, 2.5-15.0) (P <.001). The proportion of ground-glass opacification at CT was similar in patients with SSc and idiopathic NSIP but differed significantly between patients with SSc (median proportion, 49.9%; range, 0.0%-100.0%) and IPF (median proportion, 23.5%; range, 0.0%-97.2%) (P <.001). At logistic regression analysis, there were no differences in the CT features between patients with SSc and those with NSIP after controlling for age, disease extent, and the percentage predicted forced vital capacity and carbon monoxide diffusing capacity. CONCLUSION: Interstitial lung disease in patients with SSc is less extensive, less coarse, and characterized by a greater proportion of ground-glass opacification than that in patients with IPF. The CT features of lung disease in patients with SSc closely resemble those in patients with idiopathic NSIP.

Adolescent↗
PubMed2004

Prognostic implications of histologic patterns in multiple surgical lung biopsies from patients with idiopathic interstitial pneumonias.

STUDY OBJECTIVES: To determine the prevalence and prognostic significance of histologic discordance in multiple lung biopsy specimens obtained from patients investigated for suspected cryptogenic fibrosing alveolitis (CFA)/idiopathic pulmonary fibrosis (IPF). METHODS: and results: Between 1984 and 2001, 64 patients undergoing investigation for CFA/IPF were identified in whom multiple biopsies were performed that showed either a pattern of usual interstitial pneumonia (UIP) or nonspecific interstitial pneumonia (NSIP). These cases were classified into three groups: concordant UIP-UIP (n = 25, 39.1%), discordant UIP-NSIP (n = 8,12.5%), and concordant NSIP-NSIP (n = 31, 48.4%). The discordant UIP group had survival, clinical, and physiologic features similar to those of the concordant UIP group, and prognosis in both concordant and discordant UIP groups was significantly worse than that of the concordant NSIP group (p = 0.02 and p = 0.04, respectively). The age of the concordant UIP group was higher than that of the concordant NSIP group, with the mean age of the discordant group being intermediate. There were no significant differences among the three groups in smoking history, duration of dyspnea, presence or absence of crackles, FVC, diffusion capacity of the lung for carbon monoxide, or PaO(2). CONCLUSIONS: Patients with discordant UIP-NSIP results on multiple biopsies show clinical behavior similar to those with concordant UIP-UIP and should be regarded as having CFA/IPF in the correct clinical context, rather than "idiopathic NSIP" for the purposes of management. Multiple biopsies should be considered in all patients in order to improve the prognostic information provided by lung biopsy.

Age Factors↗
PubMed2004

Transforming growth factor-beta 1 and extracellular matrix-associated fibronectin expression in pulmonary lymphangioleiomyomatosis.

STUDY OBJECTIVES: Lymphangioleiomyomatosis (LAM) is a rare disorder of unknown etiology, affecting almost exclusively women of childbearing age, that is associated with the proliferation of spindle cells and cystic changes in the affected lung. The underlying processes that contribute to this disease are poorly understood. Transforming growth factor (TGF)-beta(1) is a potent cytokine that promotes mesenchymal cell proliferation and regulates the synthesis of extracellular matrix (ECM) components, particularly fibronectins. Herein, we evaluate the expression of TGF beta(1) and matrix-associated fibronectin in lung specimens demonstrating LAM. DESIGN: Lung biopsy specimens that were confirmed to contain pathologic LAM cells were obtained from 13 patients. The specimens were submitted to immunohistochemical evaluation for TGF beta(1) and fibronectin, as well as the typical markers of LAM cells. Healthy lung parenchyma surrounding resected neoplasms was studied in a parallel fashion as control tissues. MEASUREMENTS AND RESULTS: In all 13 LAM cases and in healthy lung parenchyma, we demonstrated that TGF beta(1) localized consistently to airway epithelial cells. However, in LAM tissues, matrix-associated TGF beta(1) was also consistently found in regions containing pathologic LAM cells. Notably, more abundant TGF beta(1) was observed in highly cellular areas compared to the walls of chronic cystic regions in LAM tissues. Fibronectin, a matrix component that is strongly expressed in response to active TGF beta(1) was found to consistently colocalize with this protein in these highly cellular regions, supporting TGF beta(1) activity in these regions. The markers of proliferating LAM cells, including proliferating cell nuclear antigen, were also markedly present in these highly cellular LAM regions. CONCLUSION: These studies suggest that the proliferation of aberrant LAM cells may be associated with altered regional expression of TGF beta(1) and related ECM proteins.

Actins↗
PubMed2004

Diffuse panbronchiolitis.

Diffuse panbronchiolitis (DPB) is an idiopathic inflammatory disease, largely restricted to Japan, that is characterized by progressive suppurative and obstructive airway disease, which, if left untreated, progresses to bronchiectasis, respiratory failure, and death. The lesion was first described in the early 1960s. In 1969 the name diffuse panbronchiolitis (DPB) was proposed to distinguish it from chronic bronchitis. Diffuse refers to the distribution of the lesions throughout both lungs, and pan refers to the involvement of inflammation in all layers of the respiratory bronchioles. Its distinctive imaging and histologic features, the coexisting sinusitis, and the isolation of Haemophilus influenzae and Pseudomonas aeruginosa in the sputum should enhance disease recognition. Neutrophils and T-lymphocytes, particularly CD8- cells, together with cytokines IL-8 and macrophage inflammatory protein-1 are believed to play key roles in the development of this disease. Significant improvement in the prognosis of this potentially fatal disease has been reported after the use of long-term therapy with macrolide antibiotics, the effect of which is attributed to an anti-inflammatory and immunoregulatory action.

Bronchiolitis↗
PubMed2003

Asbestosis and idiopathic pulmonary fibrosis: comparison of thin-section CT features.

PURPOSE: To identify differences, if any, in thin-section computed tomographic (CT) features between asbestosis and idiopathic pulmonary fibrosis (IPF) and to test the findings in a subset of histopathologically proved cases of usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP). MATERIALS AND METHODS: Consecutive patients with a diagnosis of IPF (n = 212) or asbestosis (n = 74) were included. The relationships derived from the initial comparison were tested in a separate group of biopsy-proved UIP (n = 30) and NSIP (n = 23) cases. Two observers independently scored thin-section CT images for extent, distribution, and coarseness of fibrosis; proportion of ground-glass opacification; severity of traction bronchiectasis; and extent of emphysema. RESULTS: After controlling for extent of fibrosis, patients with asbestosis had coarser fibrosis than those with IPF (odds ratio, 1.52; 95% CI: 1.25, 1.84; P <.001). Compared with the biopsy-proved cases, the asbestosis cases involved coarser fibrosis (after controlling for disease extent) than the NSIP cases (odds ratio, 2.48; 95% CI: 1.49, 4.11; P <.001) but fibrosis similar to that in the UIP cases. A basal and subpleural distribution of disease was usual in all subgroups but significantly more prevalent (P, <.01 to.001) with asbestosis than with UIP or NSIP. CONCLUSION: The thin-section CT pattern of asbestosis closely resembles that of biopsy-proved UIP and differs markedly from that of biopsy-proved NSIP.

Asbestosis↗
PubMed2003

Prognostic value of desaturation during a 6-minute walk test in idiopathic interstitial pneumonia.

Exercise-induced hypoxia is an index of the severity of interstitial lung disease. We hypothesized that desaturation during a 6-minute walk test would predict mortality for patients with usual interstitial pneumonia (n = 83) and nonspecific interstitial pneumonia (n = 22). Consecutive patients with biopsy-proven disease performed a 6-minute walk test between January 1996 and December 2001. Desaturation was defined as a fall in oxygen saturation to 88% or less during the 6-minute walk test. Desaturation was common (44 of 83 usual interstitial pneumonia and 8 of 22 nonspecific interstitial pneumonia; chi square, p = 0.39). Patients with usual interstitial pneumonia or nonspecific interstitial pneumonia who desaturated had a significantly higher mortality than patients who did not desaturate (respective log-rank tests, p = 0.0018, p = 0.0089). In patients with usual interstitial pneumonia, the presence of desaturation was associated with an increased hazard of death (hazard ratio, 4.2; 95% confidence interval, 1.40, 12.56; p = 0.01) after adjusting for age, sex, smoking, baseline diffusion capacity for carbon monoxide, FVC, and resting saturation. We conclude that knowledge of desaturation during a 6-minute walk test adds prognostic information for patients with usual interstitial pneumonia and nonspecific interstitial pneumonia.

Cohort Studies↗
PubMed2003

Clinical diagnosis of hypersensitivity pneumonitis.

The diagnosis of hypersensitivity pneumonitis (HP) is difficult and often relies on histopathology. Our objective was to identify diagnostic criteria and to develop a clinical prediction rule for this disease. Consecutive patients presenting a condition for which HP was considered in the differential diagnosis underwent a program of simple standardized diagnostic procedures. High-resolution computed tomography scan and bronchoalveolar lavage (BAL) defined the presence or absence of HP. Patients underwent surgical lung biopsy when the computed tomography scan, BAL, and other diagnostic procedures failed to yield a diagnosis. A cohort of 400 patients (116 with HP, 284 control subjects) provided data for the rule derivation. Six significant predictors of HP were identified: (1) exposure to a known offending antigen, (2) positive precipitating antibodies to the offending antigen, (3) recurrent episodes of symptoms, (4) inspiratory crackles on physical examination, (5) symptoms occurring 4 to 8 hours after exposure, (6) and weight loss. The area under the receiver operating characteristic curve was 0.93 (95% confidence interval: 0.90-0.95). The rule retained its accuracy when validated in a separate cohort of 261 patients. The diagnosis of HP can often be made or rejected with confidence, especially in areas of high or low prevalence, respectively, without BAL or biopsy.

Algorithms↗
PubMed2003

Fibrotic idiopathic interstitial pneumonia: the prognostic value of longitudinal functional trends.

Survival is linked to the histopathologic distinction between usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP), the most commonly encountered fibrotic idiopathic interstitial pneumonia. We retrospectively compared the prognostic significance of histopathologic diagnoses, baseline pulmonary function indices, and serial trends in pulmonary function indices (diffusing capacity, FVC, FEV1, the recently defined composite physiologic index) at 6 and 12 months in 104 patients (UIP, n = 63; fibrotic NSIP, n = 41). Survival was lower in UIP than in fibrotic NSIP (p = 0.001) but not in patients with severe functional impairment; mortality during the first 2 years was linked solely to the severity of functional impairment at presentation. The composite physiologic index was the strongest determinant of outcome (p < 0.001). At 6 months, serial diffusing capacity levels (p = 0.003) and histopathologic diagnosis (p = 0.002) were prognostically equivalent. At 12 months, serial pulmonary function trends were the only major prognostic determinant (p < 0.0005 for all variables), with no independent significance associated with the distinction between UIP and fibrotic NSIP. We conclude that at 12 months, serial pulmonary function trends have considerable prognostic value in UIP and NSIP. Their histologic distinction provides no additional prognostic information when pulmonary function trends are clear cut or when functional impairment is severe.

Aged↗
PubMed2003

Prognostic implications of physiologic and radiographic changes in idiopathic interstitial pneumonia.

Idiopathic interstitial pneumonias are a diverse group of lung diseases with varied prognoses. We hypothesized that changes in physiologic and radiographic parameters would predict survival. We retrospectively examined 80 patients with usual interstitial pneumonia and 29 patients with nonspecific interstitial pneumonia. Baseline characteristics were examined together with 6-month change in forced vital capacity, diffusing capacity for carbon monoxide, and ground glass infiltrate and fibrosis on high resolution computed tomography. Patients with usual interstitial pneumonia were more likely to have a statistically significant or marginally significant decline in lung volume, diffusing capacity for carbon monoxide, and an increase in ground glass infiltrates (p < or = 0.08) compared with patients with nonspecific interstitial pneumonia. For patients with usual interstitial pneumonia, change in forced vital capacity was the best physiologic predictor of mortality (p = 0.05). In a multivariate Cox proportional hazards model controlling for histopathologic diagnosis, gender, smoking history, baseline forced vital capacity, and 6-month change in forced vital capacity, a decrease in forced vital capacity remained an independent risk factor for mortality (decrease > 10%; hazard ratio 2.47; 95% confidence interval 1.29, 4.73; p = 0.006). We conclude that a 6-month change in forced vital capacity gives additional prognostic information to baseline features for patients with idiopathic interstitial pneumonia.

Adult↗
PubMed2003

Idiopathic pulmonary fibrosis: a composite physiologic index derived from disease extent observed by computed tomography.

In idiopathic pulmonary fibrosis, the quantitation of disease severity using pulmonary function tests is often confounded by emphysema. We have identified the composite physiologic index (CPI) most closely reflecting the morphologic extent of pulmonary fibrosis. Consecutive patients with a clinical/computed tomography (CT) diagnosis of idiopathic pulmonary fibrosis (n = 212) were divided into group I (n = 106) and group II (n = 106). The CPI was derived in group I (by fitting pulmonary function tests against disease extent on CT) and was tested in Group II. The formula for the CPI was as follows: extent of disease on CT = 91.0 - (0.65 x percent predicted diffusing capacity for carbon monoxide [DLCO]) - (0.53 x percent predicted FVC) + (0.34 x percent predicted FEV1). In group II, the CPI correlated more strongly with disease extent on CT (r2 = 0.51) than the individual pulmonary function test (DLCO the highest value, r2 = 0.38). A subanalysis demonstrated that the better fit of the CPI was ascribable to a correction of the confounding effects of emphysema. Mortality was predicted more accurately by the CPI than by a pulmonary function test in all clinical subgroups, including a separate cohort of 36 patients with histologically proven usual interstitial pneumonia (CPI, p < 0.0005; FVC, p = 0.002; PO2, p = 0.002). In conclusion, a new CPI, derived against CT and validated using split sample testing, is a more accurate prognostic determinant in usual interstitial pneumonia than an individual pulmonary function test.

Aged↗
PubMed2003

Fibroblastic foci in usual interstitial pneumonia: idiopathic versus collagen vascular disease.

A histologic feature of usual interstitial pneumonia is the presence of fibroblastic foci. As some patients with usual interstitial pneumonia and an underlying collagen vascular disease have a better prognosis, we hypothesized that they would have fewer fibroblastic foci. Pathologists reviewed surgical lung biopsies from 108 patients with usual interstitial pneumonia (nine with collagen vascular disease) and assigned a score (absent 0, mild 1, moderate 2, and marked 3) for fibroblastic foci. Patients with idiopathic usual interstitial pneumonia had a higher median profusion of fibroblastic foci (1.75 vs. 1.0, p = 0.003). Baseline characteristics were similar, although patients with a collagen vascular disease were younger, had a shorter duration of symptoms, and had a higher percentage of predicted total lung capacity. Profusion of fibroblastic foci was the most discriminative feature for separating idiopathic from collagen vascular disease-associated usual interstitial pneumonia (odds ratio 8.31; 95% confidence interval, 1.98, 59.42; p = 0.002 for a one-unit increase in fibroblastic foci score). No deaths were noted in the collagen vascular disease-associated usual interstitial pneumonia group; 52 deaths occurred in the idiopathic usual interstitial pneumonia group (log rank; p = 0.005). We conclude that patients with collagen vascular disease-associated usual interstitial pneumonia have fewer fibroblastic foci and improved survival.

Analysis of Variance↗
PubMed2003

Surgical pathology of granulomatous interstitial pneumonia.

Agranulomatous interstitial pneumonia is a form of diffuse lung disease in which granulomas are a component of the histologic findings. The differential diagnosis is quite broad, but most cases represent examples of either sarcoidosis, diffuse granulomatous infections, or hypersensitivity pneumonitis. "Hot tub lung" is a recently described form of granulomatous interstitial pneumonia that appears to have some features of diffuse infections and some features of hypersensitivity pneumonitis. The pathologist's approach to these conditions can be facilitated by giving careful attention to the anatomic distribution of the granulomas, the qualitative features of the granulomas, and the histologic changes in the lung tissue around and away from the granulomas. These features, along with the results of cultures and special stains for micro-organisms and clinical and radiologic correlation allow for a diagnosis in the vast majority of cases.

Diagnosis, Differential↗
PubMed2003

Histopathology of bronchiolar disorders.

Bronchiolar pathologic lesions result from the interplay between inflammatory and mesenchymal cells following injury to bronchioles. Offending agents include viruses, bacteria, fungi, cigarette smoke, toxic inhalants, inorganic dusts, allergens, and systemic or localized autoimmune or inflammatory processes. Bronchiolar pathologic lesions also arise in the context of allograft transplantation and pathology of the large airways and in the setting of an idiopathic disorder. Given the great variety of sources of injury and diversity of clinical, radiological, and functional patterns that result, it is no surprise that most morphological abnormalities of the bronchioles are not specific. They thus represent a diagnostic challenge to the surgical pathologist, and the necessity of a multidisciplinary (clinical/radiological/pathologic) approach cannot be overemphasized. After a survey of the normal histology of bronchioles, we present a pragmatic classification that reflects the spectrum of bronchiolar pathology, illustrating the intimate interdependence of clinical, radiological, and pathologic findings in assessing the significance of bronchiolar lesions. This classification is intended to be applicable to surgical pathology material that can be correlated with clinical disease syndromes. It includes asthma-associated bronchiolar changes, chronic bronchitis/emphysema-associated bronchiolar changes, cellular bronchiolitis, respiratory bronchiolitis, bronchiolitis obliterans with intraluminal polyps/ BOOP, constrictive bronchiolitis, mineral dust small airway disease, peribronchiolar fibrosis and bronchiolar metaplasia, and bronchiolocentric nodules.

Journal Article↗
PubMed2003

Noninfectious lung pathology in patients with Crohn's disease.

Lung involvement in Crohn's disease is not well characterized. We reviewed our experience with 11 lung biopsies (seven wedge and four transbronchial) from patients with Crohn's disease to study this association further. Negative cultures, special stains for organisms Gomori-methenamine-silver [GMS], acid fast), and polymerase chain reaction for (four cases) were required for inclusion. The group included five women and six men with a mean age of 47 years (range 13-84 years). A diagnosis of Crohn's disease preceded the lung disease in nine patients. In two patients the diagnosis of Crohn's disease followed the diagnosis of their pulmonary disease 1 and 15 months later. Radiologically, eight patients had diffuse infiltrates, two had bilateral nodular infiltrates, and one had a mass. Chronic bronchiolitis with nonnecrotizing granulomatous inflammation was present in four patients, one of whom was taking mesalamine. Two patients had an acute bronchiolitis associated with a neutrophil-rich bronchopneumonia with suppuration and vague granulomatous features. One patient on mesalamine had cellular interstitial pneumonia with rare giant cells. Four patients demonstrated organizing pneumonia with focal granulomatous features, two of whom were taking mesalamine, and one of these two responded to infliximab (anti-tumor necrosis factor) monoclonal antibody therapy. Noninfectious pulmonary disease in patients with Crohn's disease has variable histologic appearances, including granulomatous inflammation and airway-centered disease resembling that seen in patients with ulcerative colitis. Drugs may contribute to pulmonary disease in some patients.

Adult↗
PubMed2003

The overlap between respiratory bronchiolitis and desquamative interstitial pneumonia in pulmonary Langerhans cell histiocytosis: high-resolution CT, histologic, and functional correlations.

OBJECTIVES: To characterize the histologic, high-resolution CT (HRCT), and functional correlates of respiratory bronchiolitis (RB)/desquamative interstitial pneumonia (DIP)-like changes in biopsy specimens of adults with pulmonary Langerhans cell histiocytosis (PLCH). METHODS: We retrospectively identified 14 adult patients with histologically proven PLCH (all smokers) in whom both biopsy specimens and HRCT were available for review. The presence and extent of RB/DIP-like changes on lung biopsy specimens of patients with PLCH were correlated with total pack-years of smoking, lung function variables, and the presence of ground-glass attenuation on HRCT. RESULTS: Varying degrees of RB/DIP-like changes were identified in all biopsy specimens. The extent of involvement with RB/DIP-like changes correlated with the cumulative exposure to cigarettes smoked at the time of biopsy (r = 0.61, p = 0.03). Ground-glass attenuation was detected in three HRCTs, two of which had extensive RB/DIP-like changes (> or = 70% involvement) on histology, suggesting that substantial smoking-induced RB/DIP-like changes may be the cause of ground-glass attenuation on the HRCT of patients with PLCH. No correlation was found between the extent of RB/DIP-like changes and total lung capacity, FEV(1), or diffusion capacity of the lung for carbon monoxide. CONCLUSIONS: RB/DIP-like changes are exceedingly common in PLCH, may be sufficiently severe to cause the appearance of ground-glass attenuation on HRCT, and correlate with the cumulative exposure to cigarettes smoked. This study provides additional evidence that PLCH, RB, and DIP form a spectrum of interstitial patterns of lung injury to cigarette smoke.

Bronchiolitis↗