Biomedical subjects

P Soler

Publications and source records attributed to P Soler.

At least 73 records · Page 4Linked to original sources

PubMed1991

Glucose, K+, and albumin concentrations in the alveolar milieu of normal humans and pulmonary sarcoidosis patients.

Some properties of the alveolar epithelial barrier during transalveolar transport of water and solutes were studied in normal humans and patients with sarcoidosis by means of the transalveolar capillary concentration gradients of various solutes. A total of 9 normal control subjects (Group A) and 60 sarcoidosis patients, 52 with an evolving disease (Group B) and 8 recovered (Group C), underwent bronchoalveolar lavage (BAL). The second aliquot of fluid was used to measure urea, glucose, potassium, and albumin, which were also investigated in plasma. Urea was used to determine the volume of alveolar epithelial lining fluid (AELF volume). Results are expressed as the ratio of solute concentration in AELF over that in plasma (A/P ratio). In Group A there were clear concentration gradients of glucose, potassium, and albumin between the AELF and plasma, as the A/P ratios of glucose, potassium, and albumin were 0.02 +/- 0.006 (mean +/- SEM), 3.2 +/- 0.34, and 0.04 +/- 0.008, respectively. In Group B the A/P ratios of glucose (0.21 +/- 0.02, p less than 0.001) and albumin (0.17 +/- 0.02, p less than 0.001) were significantly increased but that of potassium remained unchanged (2.9 +/- 0.2). The A/P ratios of these various solutes were independent of chest x-ray typing. The albumin but not the glucose A/P ratio was correlated with the percentage of lymphocytes recovered from BAL (p less than 0.02); however, there was no correlation between the albumin A/P ratio and the CD4+/CD8+ T lymphocyte ratio. In group C there was a striking contrast between the albumin A/P ratio, which was normal, and the glucose A/P ratio, which was clearly elevated despite a normal lymphocyte count.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

Expression of 1,25(OH)2D3 receptors on alveolar lymphocytes from patients with pulmonary granulomatous diseases.

1,25(OH)2D3 is known to be produced at sites of granulomatous reactions. In order to characterize the cell types that are targets for this immunoregulatory hormone, we have evaluated the expression of 1,25(OH)2D3 receptors on peripheral blood T-lymphocytes and those recovered from the lung by bronchoalveolar lavage from patients with pulmonary granulomatous diseases (tuberculosis and sarcoidosis) and from normal control subjects using combined autoradiographic and immunohistochemical techniques. Lavage T-lymphocytes from patients with tuberculosis or with sarcoidosis, but not those from normal control subjects, expressed 1,25(OH)2D3 receptors as demonstrated by binding of [3H]1,25(OH)2D3, which was inhibited by the presence of excess unlabeled 1,25(OH)2D3, but not by the presence of unlabeled 25(OH)D3 (receptor-positive lymphocytes: sarcoidosis, 20 +/- 12%; tuberculosis, 31 +/- 17%). In contrast, blood lymphocytes from patients with granulomatous diseases did not express detectable 1,25(OH)2D3 receptors. The percentage of lavage T-lymphocytes expressing 1,25(OH)2D3 receptors was significantly greater for patients with tuberculosis presenting with isolated hilar adenopathy than for patients with pulmonary infiltrates and/or cavities. 1,25(OH)2D3 receptors were expressed to a greater extent on CD8+ T-lymphocytes than on CD4+ T-lymphocytes in sarcoidosis, whereas a greater proportion of CD4+ than of CD8+ T-lymphocytes from patients with tuberculosis were receptor-positive. These findings support the conclusion that the interaction of 1,25(OH)2D3 with its receptor on T-lymphocytes may play an important role in the regulation of granulomatous reactions, but because these receptors are expressed on different lymphocyte populations, the net effect of this potent immunoregulatory molecule is likely different in sarcoidosis and tuberculosis.

Adult↗

PubMed1991

Bronchoalveolar mast cells in normal farmers and subjects with farmer's lung. Diagnostic, prognostic, and physiologic significance.

To evaluate the specificity and significance of increased lavage mast cells in farmer's lung, we examined the lavage cell differentials of 89 farmers and 19 normal nonfarming control subjects. The farmers were divided into four groups: acute farmer's lung (n = 17), farmers with one or more prior episodes of farmer's lung who remained in daily contact with hay (n = 26) or quit farming (n = 14), and normal farmers (n = 36). A total of 14 of the subjects with prior episodes of farmer's lung and still farming and 15 normal farmers were evaluated twice at a 2-yr interval. The lavage mast cell numbers were significantly higher in acute farmer's lung (7.5 +/- 7.3 x 10(3)/ml, mean +/- SD) and ex-farmer's lung who were still farming (1.2 +/- 1.3 x 10(3)/ml) than in normal farmers (0.1 +/- 0.1 x 10(3)/ml) (p less than 0.01). A total of 8 of 14 exfarmer's lung patients who had quit farming and 18 of 36 normal farmers had an increased number of mast cells in lavage, but mast cell count never exceeded 0.5% of total recovered cells. In the acute farmer's lung and ex-farmer's lung-still farming groups, the mast cell count correlated with the lymphocyte count: r = 0.83 and r = 0.69 (p less than 0.001), respectively. In the two groups evaluated twice, mast cell numbers at the first study did not correlate with changes seen at the second study in chest roentgenogram and pulmonary functions. We conclude that an increase in lavage mast cells occurs commonly as a part of the immune response against thermophilic bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1991

Gamma/delta T-lymphocytes are not increased in number in granulomatous lesions of patients with tuberculosis or sarcoidosis.

gamma delta T-lymphocytes have been suggested to play a role in granuloma formation and to participate in the immune responses observed in tuberculosis and sarcoidosis. To further evaluate the role of gamma delta T-lymphocytes in these disorders, we used immunohistochemical techniques and specific monoclonal antibodies to characterize the number of distribution of T-lymphocytes expressing alpha beta and gamma delta T-cell receptors in granulomatous lesions from patients with sarcoidosis (n = 8) or tuberculosis (n = 4). The vast majority of T-lymphocytes present in lymph nodes from patients with tuberculosis or sarcoidosis expressed alpha beta TCR, whereas only rare gamma delta T-lymphocytes were observed inside or at the periphery of the granulomas. Recently formed granulomas induced by positive Kveim test reactions in patients with sarcoidosis also contained only small numbers of gamma delta T-lymphocytes, including those present in biopsies from two patients with increased numbers of circulating gamma delta T-lymphocytes. These observations demonstrate that T-cells involved in immune granulomatous reactions in sarcoidosis and tuberculosis express predominantly alpha beta TCR, and they do not support the conclusion that gamma delta T-lymphocytes necessarily play an important role in granuloma formation.

Adult↗

PubMed1991

[Pulmonary dendritic cells].

The dendritic cells were initially described in lymphoid organs and have been recently shown in the normal human lung at the level of the bronchioles, preferentially in the peribronchiolar connective tissue and in the alveolar parenchyma. Langerhans cells, which constitute a sub-population amongst the dendritic cells are equally present, but virtually exclusively limited to the bronchiolar epithelium. The pulmonary Langerhans cells probably derive from dendritic cells as in the skin. The number and state of differentiation of pulmonary dendritic cells vary as a function of the epithelial microenvironment which seems necessary in the differentiation of dendritic cells into Langerhans cells. Langerhans cells are frequently seen in zones of alveolar hyperplasia and/or alveolar metaplasia induced by tobacco or by inflammatory lesions. Dendritic cells and Langerhans cells have a potent capacity for presenting an antigen to lymphocytes. Their presence in the normal lung and their differentiation in the course of certain pathological pulmonary processes strongly suggest that they have a significant role in the pulmonary immune response as well as in the pathogenesis of certain diseases.

Dendritic Cells↗

PubMed1990

Bronchoalveolar lavage for rapid diagnosis of the fat embolism syndrome in trauma patients.

OBJECTIVE: To evaluate the usefulness of bronchoalveolar lavage in establishing the diagnosis of the fat embolism syndrome in trauma patients with long-bone fractures. DESIGN: Case series. SETTING: Referral hospital. PATIENTS: Eighteen trauma patients with long-bone fractures, including 5 with definite fat embolism syndrome, 5 in whom the diagnosis had been clinically suspected but was impossible to confirm or exclude before bronchoscopy, and 8 with no clinical evidence of the syndrome. Control groups included 9 patients without previous trauma who developed the adult respiratory distress syndrome for various reasons and 15 normal volunteers. MEASUREMENTS AND MAIN RESULTS: Each patient had fiber-optic bronchoscopy with bronchoalveolar lavage, and the percentage of lavage cells containing intracellular fat droplets stained with oil red 0 were determined. In the five patients with definite fat embolism syndrome, light microscopic study of bronchoalveolar cells stained with oil red 0 showed many large intracellular fat droplets (mean percentage of cells containing fat droplets, 63%; range, 31% to 82%), whereas less than 2% of cells recovered by lavage from trauma patients with no clinical evidence of the syndrome, from patients with the adult respiratory distress syndrome, or from normal volunteers contained such inclusions. Use of the same technique in the five patients with possible fat embolism syndrome permitted the immediate identification of three patients in whom this diagnosis was later confirmed by subsequent autopsy or clinical follow-up. CONCLUSIONS: The identification of fat droplets within cells recovered by bronchoalveolar lavage in trauma patients may be a rapid and specific method for establishing the diagnosis of the fat embolism syndrome.

Adolescent↗

PubMed1990

Abnormal epithelial cells recovered by bronchoalveolar lavage: are they malignant?

The recovery of neoplastic cells by bronchoalveolar lavage is useful in the diagnosis of lung cancer. Abnormal epithelial cells can also be recovered from patients with interstitial lung diseases who do not have cancer, and therefore the usefulness of lavage in the diagnosis of malignancy in this setting is unknown. In this study, we evaluated the diagnostic significance of abnormal lavage cells recovered from patients with diffuse parenchymal abnormalities and compared the usefulness of standard cytologic assessment, correlation with clinical features, and immunocytochemical staining for carcinoembryonic antigen (CEA) in identifying abnormal cells that are truly malignant. Thirty of 2,314 patients had atypical lavage cells, but in only nine was lung cancer demonstrated. Although most patients with clinical suspicion of malignancy had lung carcinoma (six of seven), one such patient did not have cancer, and three were shown to have unsuspected carcinoma. Cytologic criteria identified definitely malignant cells in only four of nine patients with lung cancer, indicating that the approach is not sensitive. Immunostaining of abnormal cells with anti-CEA antibodies proved helpful. All patients with lung malignancy had CEA+ cells (n = 9), and no patient whose abnormal cells were CEA- proved to have cancer (n = 17). Because only nine of 13 patients with CEA+ cells had lung malignancy, the test is not diagnostic, but it appears to limit the need for further evaluation to a smaller group of patients in whom cancer is likely to be present. When used together, cytopathologic findings, detection of CEA by immunocytochemical techniques, and clinical correlates proved useful in diagnosis of lung malignancy, but further improvements are still needed to improve diagnostic accuracy.

Bronchoalveolar Lavage Fluid↗

PubMed1990

Intraluminal fibrosis and elastic fiber degradation lead to lung remodeling in pulmonary Langerhans cell granulomatosis (histiocytosis X).

To evaluate the morphogenesis of lung remodeling in pulmonary Langerhans cell granulomatosis (LCG; previously called histiocytosis X or eosinophilic granuloma), lung tissues obtained by open biopsy from 62 patients with pulmonary LCG were studied by light and electron microscopy. Tissues from 20 patients were also studied by immunohistochemical methods for the detection of fibronectin, elastin, and S-100 protein, and samples from six patients were studied using OKT6 monoclonal antibody. In early stages of pulmonary LCG, the epithelial lining cells were detached and Langerhans cells, inflammatory cells, and myofibroblasts migrated into intraluminal spaces through gaps in the epithelial basement membranes in and around the granulomatous lesions. In late stages, intraluminal fibrosis led to obstruction of alveolar spaces and airways and to coalescence of alveolar walls in and around the granulomatous lesions. Adjacent to these lesions, irregularly dilated alveoli were found with degraded and disrupted elastic fibers. Together, these observations suggest that intraluminal fibrosis and elastic fiber degradation are important processes of lung remodeling in pulmonary LCG.

Antibodies, Monoclonal↗

PubMed1989

Cigarette smoking-induced changes in the number and differentiated state of pulmonary dendritic cells/Langerhans cells.

To evaluate the effect of cigarette smoking on the number, distribution, and differentiated state of dendritic cells (DC) and Langerhans cells (LC) in the human lung, we have quantitated the number of these cells present in the bronchioles and alveolar parenchyma of lung tissue from nonsmokers and cigarette smokers using anti-CD1 monoclonal antibodies which react preferentially with DC (M241) and LC (T6). M241+ DC were found in the bronchiolar submucosa and alveolar parenchyma of nonsmokers; T6+ LC were present within the bronchiolar epithelium. Cigarette smoking was associated with a twofold increase in the total number of cells of DC/LC lineage and a 30-fold increase in the number of T6+ cells, many of which contained Birbeck granules (LC), present in the alveolar parenchyma. Most LC found in the parenchyma of smokers were observed in close association with areas of alveolar type II pneumocyte hyperplasia. Cigarette smoking did not change the number of differentiated state of cells of DC/LC lineage within the bronchioles. Both DC and LC are present in the human lung. Cigarette smoking has an important effect on the number, distribution, and differentiated state of these cells, which may explain why most adult patients who develop Langerhans cell granulomatosis are smokers.

Adult↗

PubMed1989

Urinary neopterin in pulmonary sarcoidosis. Relationship to clinical and biologic assessment of the disease.

Neopterin is a metabolite of guanosine-triphosphate, released in vitro by macrophages under the control of gamma-interferon and described as a marker of T cell activation in vivo. We have compared the urinary neopterin/creatinine ratio (mumol/mol) in patients with pulmonary sarcoidosis (n = 66), interstitial lung diseases other than sarcoidosis (nonsarcoid ILD, n = 35), and 45 normal control subjects. For the sarcoid population as a whole, urinary neopterin was higher (496 +/- 52 mumol/mol [mean +/- SEM]) than in control subjects (126 +/- 5 mumol/mol) (p less than 0.001). In patients with nonsarcoid ILD, urinary neopterin was frequently higher in granulomatous and/or lymphoproliferative diseases (hypersensitivity pneumonitis, tuberculosis, primitive Sjögren's syndrome, and malignant lymphomas) (781 +/- 193 mumol/mol, n = 10) but remained normal in other types of nonsarcoid ILD [( 163 +/- 14 mumol/mol, n = 25]: histiocytosis X, idiopathic pulmonary fibrosis, lung collagen-vascular diseases, diffuse neoplasms, pneumoconiosis; p less than 0.001 compared with sarcoidosis). We have also evaluated the relationship between urinary neopterin and the clinical or biologic markers currently used to assess sarcoidosis: alveolar lymphocytosis in lavage fluid (ALY), 67-gallium scan semiquantitative index (67Ga), or serum angiotensin-converting enzyme (SACE). Sarcoid patients with the highest urinary neopterin were those in whom mean values of these markers were the highest (p less than 0.05, all comparisons). Patients with positive markers (i.e., either clinical expression of sarcoidosis-ALY greater than 30%-67Ga greater than 20-SACE greater than 60 U/ml) had significantly higher urinary neopterin levels than did other sarcoid patients (p less than 0.05, all comparisons).

Adult↗

PubMed1988

Diagnosis of nosocomial bacterial pneumonia in intubated patients undergoing ventilation: comparison of the usefulness of bronchoalveolar lavage and the protected specimen brush.

PURPOSE: To compare the usefulness of specimens recovered using a protected specimen brush and those recovered by bronchoalveolar lavage in the diagnosis of nosocomial pneumonia occurring in intubated patients undergoing ventilation, we performed both procedures in patients suspected of having pneumonia because of the presence of a new pulmonary infiltrate and purulent tracheal secretions. PATIENTS AND METHODS: Twenty-one patients (16 men and five women) with an average age of 57 +/- 12 years were studied. They had been receiving mechanical ventilation for 8 +/- 6 days before inclusion in the trial. The clinical suspicion for nosocomial bacterial pneumonia was high in these patients. Fiberoptic bronchoscopy was performed in each patient. Bronchoscopy specimens were obtained by a protected specimen brush and by bronchoalveolar lavage, and were then processed for quantitative bacterial and fungal culture using standard methods. Total cell counts were performed on an aliquot of resuspended original lavage fluid. Differential cell counts were made on at least 500 cells. In addition, 300 cells were examined at high-power magnification and the percentage of cells containing intracellular microorganisms and the average number of extracellular organisms per oil-immersion field were determined. RESULTS: Quantitative culture of specimens recovered using the protected specimen brush were positive (more than 10(3) colony-forming units [cfu]/ml) in five of five patients with subsequently confirmed pneumonia, and negative (less than 10(3) cfu/ml) in 13 of 13 patients without bacterial pneumonia, but results were not available until 24 to 48 hours after the procedure. Quantification of intracellular organisms in cells recovered by lavage was also useful in distinguishing patients with pneumonia (more than 25 percent of cells with intracellular organisms in five of five patients) from those without pneumonia (less than 15 percent of cells with intracellular organisms in all cases), and results were available immediately. In contrast, quantitative culture of lavage fluid and differential cell counts were of little value in identifying infected patients. CONCLUSION: The protected specimen brush and microscopic identification of intracellular organisms in cells recovered by lavage yield useful and complementary information, and together permit rapid and specific treatment of most patients with nosocomial pneumonia.

Bacteria↗

PubMed1988

Smoking and pulmonary sarcoidosis: effect of cigarette smoking on prevalence, clinical manifestations, alveolitis, and evolution of the disease.

Patients with pulmonary sarcoidosis are less likely to smoke than persons of a similar age in the general population. This could be because smoking reduces the likelihood of developing sarcoidosis, or alternatively smoking could reduce the severity of the disease process so that smoking patients are underrepresented among patients with clinically overt disease. To evaluate these possibilities 64 patients with sarcoidosis of recent onset were studied at presentation and after a one year follow up period, clinical, functional, radiographic, and bronchoalveolar lavage fluid criteria being used to identify factors that might account for the lower incidence of sarcoidosis in smokers and to determine whether the disease is less severe in smoking patients. Smoking was less common in the patients with sarcoidosis (30%) than in the control subjects (46%). The study did not support the conclusion that sarcoidosis is less severe in smokers, as clinical, radiographic, and functional abnormalities were similar in smokers and non-smokers at initial evaluation and after a one year follow up period. Nevertheless, smoking did influence various indices used to assess disease "activity." Cigarette smoking was associated with a significant increase in the serum angiotensin converting enzyme activity (SACE), and patients with very high SACE and pulmonary gallium-67 uptake were smokers. Furthermore, more CD8+ (but not CD4+) lymphocytes were recovered by lavage from smoking than from non-smoking patients, giving a lower CD4: CD8 ratio in smokers. Fewer alveolar macrophages were recovered by lavage from smokers with sarcoidosis than from normal subjects with a similar smoking history. These finding support the possibility that smokers, particularly those with a prominent accumulation of alveolar macrophages in the lower respiratory tract, may be less likely to develop sarcoidosis.

Adult↗

PubMed1988

T-lymphocytes recovered by bronchoalveolar lavage from normal subjects and patients with sarcoidosis are refractory to proliferative signals.

Granuloma formation in the lung of patients with sarcoidosis is preceded by the accumulation of large numbers of activated T-lymphocytes, which results, at least in part, from the proliferation of T-lymphocytes within the lung. To determine whether the increased proliferation of lung T-lymphocytes in sarcoidosis results from a failure of mechanisms responsible for limiting their proliferation, we have compared the ability of purified T-lymphocytes present in bronchoalveolar lavage fluid and peripheral blood from normal subjects and patients with sarcoidosis to respond to proliferative signals. The mitogen-induced proliferative response of lavage T-lymphocytes from normal subjects and patients with sarcoidosis was similar, but the response of lavage T-lymphocytes was much less than that observed using normal or sarcoid blood T-lymphocytes. The reduced proliferative response of sarcoid lavage T-lymphocytes could not be overcome by addition of accessory cells or exogenous interleukin-2, and it did not result from the presence of suppressor cells. Furthermore, sarcoid lavage lymphocytes are capable of being activated by "mitogenic" signals, as indicated by the ability of phytohemagglutinin to induce expression of the 4F2 surface antigen and stimulate interleukin-2 production. However, the expression of interleukin-2 receptors was reduced on stimulated sarcoid lavage T-lymphocytes compared with that observed on normal blood T-lymphocytes, which may account in part for their reduced proliferative capacity. Because mechanisms that render lavage T-lymphocytes from normal subjects refractory to proliferative signals appear to operate in sarcoidosis as well, these findings suggest that a defect in the inhibition of T-lymphocyte proliferation is unlikely to be an important cause of lymphocyte accumulation in this disorder.

Adult↗

PubMed1988

High inflation pressure pulmonary edema. Respective effects of high airway pressure, high tidal volume, and positive end-expiratory pressure.

The respective roles of high pressure and high tidal volume to promote high airway pressure pulmonary edema are unclear. Positive end-expiratory pressure (PEEP) was shown to reduce lung water content in this type of edema, but its possible effects on cellular lesions were not documented. We compared the consequences of normal tidal volume ventilation in mechanically ventilated rats at a high airway pressure (HiP-LoV) with those of high tidal volume ventilation at a high (HiP-HiV) or low (LoP-HiV) airway pressure and the effects of PEEP (10 cm H2O) on both edema and lung ultrastructure. Pulmonary edema was assessed by extravascular lung water content and microvascular permeability by the drug lung weight and the distribution space of 125I-labeled albumin. HiP-LoV rat lungs were not different from those of controls (7 cm H2O peak pressure ventilation). By contrast, the lungs from the groups submitted to high volume ventilation had significant permeability type edema. This edema was more pronounced in LoP-HiV rats. It was markedly reduced by PEEP, which, in addition, preserved the normal ultrastructural aspect of the alveolar epithelium. This was in striking contrast to the diffuse alveolar damage usually encountered in this type of edema. To our knowledge, this constitutes the first example of a protective effect of PEEP during permeability edema.

Animals↗

PubMed1987

In situ characterization of cells in periapical granuloma by monoclonal antibodies.

Monoclonal antibodies were used in histopathologic and immunohistologic studies of periapical granulomas. In cellular zones, plasma cells and lymphocytes predominated, with variable numbers of fibroblasts, macrophages, and polymorphonuclear leukocytes. Labeling with monoclonal antibodies disclosed relatively infrequent, usually scattered macrophages. Plasma cells were numerous and frequently clumped. The vast majority of lymphocytes were T cells, scattered individually or in small groups of three or four cells and dispersed throughout the granulomas without any topographic predilection, with prevalence of T-suppressor/cytotoxic cells over T-helper/inducer cells. Our findings of numerous plasma cells, which were in agreement with descriptions of numerous immunoglobulin-producing cells by other authors, imply the participation of antibody-mediated immune reactions in periapical granulomas. The presence of cell-mediated immunity, in spite of numerous T cells, could not be confirmed.

Adolescent↗

PubMed1987

Pulmonary disposition of roxithromycin (RU 28965), a new macrolide antibiotic.

The penetration of roxithromycin (RU 28965), an ether oxime derivative of erythromycin, into the cells and fluid lining the epithelial surface of the lower respiratory tract was studied by performing fiber-optic bronchoscopy with bronchoalveolar lavage on eight patients who had received roxithromycin at 300 mg perorally every 12 h for 5 days. The apparent volume of epithelial lining fluid recovered by bronchoalveolar lavage was determined by using urea as an endogenous marker. There was a significant relationship (r = 0.75; P less than 0.02) between roxithromycin levels in plasma and epithelial lining fluid, with a correlation whose slope suggested that the level of drug penetration into the lining fluid was 0.2. Concentrations of the antibiotic in cells recovered by bronchoalveolar lavage (21 +/- 10 micrograms/ml) were 2 and 10 times higher than in plasma (11.4 +/- 5.7 micrograms/ml) and epithelial lining fluid (2.0 +/- 1.7 micrograms/ml), respectively. Thus, when administered perorally in humans, roxithromycin is markedly accumulated by resident alveolar macrophages in concentrations largely exceeding the MBCs of the drug for most facultative intracellular pathogens including Legionella pneumophila, despite low concentrations in the epithelial lining fluid.

Bronchitis↗

PubMed1987

Role of mast cells in the pathogenesis of hypersensitivity pneumonitis.

To examine the possibility that mast cells have a central role in the pathogenesis of hypersensitivity pneumonitis, 20 patients with this disease were studied with the aim of seeking evidence for mast cell degranulation. The number of mast cells recovered by bronchoalveolar lavage from patients with hypersensitivity pneumonitis was more than 1,000 times greater than those recovered from normal individuals. Furthermore, discontinuation of antigen exposure resulted in an increase in the number of mast cells observed, consistent with the possibility that antigen exposure had induced mast cell degranulation. Cessation of antigen exposure also resulted in a rapid decrease in the number of neutrophils and eosinophils recovered by lavage, followed by an increase in the number of T8+ T lymphocytes present. In each case the time course of the changes was consistent with the possibility that mast cell degranulation had been important in regulating the number of the immune and inflammatory cells present in the lung. Histamine was present in lavage fluid supernatant from patients with hypersensitivity pneumonitis. The amount of histamine present was, however, closely correlated with the number of mast cells present and not with the interval since last antigen exposure. Delay in separating cells from lavage fluid supernatant resulted in an increase in histamine content. These results suggest that the free histamine in lavage fluid resulted from the degranulation of mast cells induced by the lavage procedure as histamine released in vivo has a short half life. We suggest that hypersensitivity pneumonitis results from a "late phase reaction" initiated by antigen induced mast cell degranulation.

Alveolitis, Extrinsic Allergic↗

PubMed1987

Acute and latent pneumonitis after subcutaneous injections of silicone in transsexual men.

We evaluated 13 transsexual men who were hospitalized for symptoms resulting from illicit subcutaneous injections of silicone. Patients with acute silicone pneumonitis were admitted because of fever, bilateral pulmonary infiltrates, and hypoxemia (mean PaO2, 58 +/- 14 mm Hg). Most patients in this group had received new silicone injections within hours of admission, but one presented with the same clinical syndrome a few hours after a brawl. The alveolitis of acute silicone pneumonitis was characterized by increased numbers of alveolar macrophages, neutrophils, and eosinophils (p less than 0.05 compared with those in normal persons with a similar smoking history). Evidence of alveolar hemorrhage was also present in some cases. Alveolar macrophages contained large, pleomorphic, cytoplasmic inclusions, which were identified as silicone by atomic absorption and infrared spectrometry. Patients with latent silicone pneumonitis underwent clinical study at much longer times after the silicone fluid injections because they developed local inflammatory phenomena at the sites of previous injections. Pulmonary function studies usually showed slight restrictive changes, and bronchoalveolar lavage disclosed abnormalities similar to those found in patients with acute silicone pneumonitis, although to a lesser degree. Thus, illicit silicone fluid injection carries a serious respiratory risk since it can induce pneumonitis, followed in some patients by respiratory failure.

Acute Disease↗