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G R Epler

Publications and source records attributed to G R Epler.

35 records · Page 2Linked to original sources
PubMed1985

Diffuse pleural thickening in an asbestos-exposed population: prevalence and causes.

Two types of pleural reaction have been described in association with asbestos exposure: pleural plaques and diffuse pleural thickening. This study was undertaken to determine the prevalence and causes of diffuse thickening in asbestos-exposed persons. Serial chest radiographs in 1373 exposed individuals and 717 controls were interpreted according to the ILO scheme by two B readers. Diffuse pleural thickening was defined as a smooth, noninterrupted pleural density extending over at least one-fourth of the chest wall, with or without costophrenic angle obliteration. Among the exposed group, plaques and diffuse thickening occurred with almost equal frequency, 16.5% and 13.5%, respectively. Of the 185 cases with diffuse thickening, the radiographic appearance was most often due to the residual of a benign asbestos effusion (31.3%) or confluent plaques (25.4%). The most commonly held explanation of diffuse thickening, an extension of pulmonary fibrosis to the visceral and parietal pleura, was actually infrequent (10.2%). Among the group with diffuse thickening without asbestosis, the forced vital capacity and single-breath diffusing capacity were significantly lower than those of comparable normal persons and those with confluent plaques.

Asbestosis↗
PubMed1984

Prevalence survey of respiratory abnormalities in New Mexico uranium miners.

To obtain additional data concerning uranium mining and nonmalignant respiratory diseases, we conducted a prevalence survey of 192 long-term New Mexico uranium miners. Survey procedures included spirometry, completion of a respiratory symptoms questionnaire, physical examination and interpretation of available chest x rays. Total duration of underground uranium mining was used as the exposure index. Of the major respiratory symptoms, only the prevalence of dyspnea increased significantly with duration of uranium mining. With linear multiple-regression analysis, small but statistically significant effects of mining were found for two spirometric parameters, the forced expiratory volume in one sec and the maximal midexpiratory flow. By the 1980 International Labor Organization (ILO) U/C classification, 12 of 143 participants with x rays available for interpretation had at least category 1/0 pneumoconiosis. The opacities were predominantly nodular and compatible with silicosis.

Adult↗
PubMed1984

Exercise alveolar-arterial oxygen pressure difference in interstitial lung disease.

Abnormality of gas exchange is best evaluated by the exercise alveolar-arterial oxygen pressure difference, P(A-a)O2. We studied the P(A-a)O2 in 168 patients with sarcoidosis, desquamative interstitial pneumonia (DIP), usual interstitial pneumonia (UIP), berylliosis, and asbestosis who were seen for clinical and disability consultations. The increase of P(A-a)O2 with exercise was greatest in UIP (mean 16 mm Hg), least in sarcoidosis (mean 1 mm Hg), and intermediate in DIP, berylliosis, and asbestosis (means 9, 9, and 7 mm Hg, respectively). The increase was best predicted by the single breath diffusing capacity (Dsb), and it occurred in patients with sarcoidosis and DIP if the Dsb was less than 50 percent predicted and in patients with the other diseases if the Dsb was less than 70 percent predicted. However, the magnitude of the increase could not be predicted from resting tests, even when multilinear regression equations were used. We conclude that for clinical evaluation of patients with interstitial lung disease, the exercise test with arterial blood gas measurement adds important information if the Dsb is less than 70 percent predicted. For disability evaluation, the invasive exercise study may be helpful when there is a wide discrepancy between clinical findings and resting physiologic studies.

Adult↗
PubMed1982

Prevalence and incidence of benign asbestos pleural effusion in a working population.

Benign asbestos effusion was defined by (1) exposure to asbestos, (2) confirmation by roentgenograms or thoracenteses, (3) no other disease related to pleural effusion, and (4) no malignant tumor within three years. There were 34 benign effusions among 1,135 exposed workers compared with no otherwise unexplained effusions among 717 control subjects. Prevalence was dose related with 7.0%, 3.7%, and 0.2% effusions with severe (III), indirect (II), and peripheral (I) exposure, respectively. The latency period was shorter than for other asbestos-related disorders. Benign effusion was the most common asbestos-related abnormality during the first 20 years after exposure. Incidence studies showed 9.2 effusions per 1,000 person-years for level III exposure, 3.9 for level II, and 0.7 for level I. Most effusions were small; 28.6% recurred, and 66% were asymptomatic. There was one mesothelioma six years after effusion. Asbestos exposure should be carefully searched for in patients with "idiopathic" pleural effusion.

Adult↗
PubMed1980

Asbestos-related disease from household exposure.

The importance of nonoccupational asbestos exposure has been emphasized recently. To illustrate this problem, we report 4 persons with asbestos-related disease from household exposure. There were 2 wives of asbestos workers, who cleaned their husbands' work clothes. One developed a mesothelioma and the other plaques, calcification, benign asbestos pleural effusion and subpleural parenchymal fibrosis. 2 men were exposed as children while playing in a cellar room which was also used for their father's muffler repair business. At ages 27 and 33, they had pleural and diaphragmatic calcifications.

Adult↗
PubMed1980

Calibration of time derivatives of forced vital capacity by explosive decompression.

A simple, portable, inexpensive device is described that simulates expiratory flow curves for calibration of spirometers. A 4-L metal cylinder filled with copper mesh is fitted with a precision manometer. The pressure is increased to twice atmospheric and released by explosive decompression through 4 easily interchangeable resistors. The ratio of forced expiratory volume in one second to forced vital capacity ranged from 0.80 to 0.25, thus encompassing the range from normal to severe obstruction. Accuracy was defined by 25 measurements of forced vital capacity that differed by no more than 0.5% from the actual cylinder volume. Repeatability was reflected by a standard deviation of at most 0.04 L/s for one-second forced expiratory volume, mid-expiratory flow, and instantaneous flows at 50 and 25% of the forced vital capacity. Peak flow was less reproducible. Calibrations of a water spirometer at increased altitude and at temperatures from 4 degrees to 37 degrees C revealed no significant changes in volume or flow rates. Standard values have remained unchanged for 2.5 yr. Three volume spirometers and 2 primary flow devices were tested extensively.

Altitude↗
PubMed1980

Determination of severe impairment (disability) in interstitial lung disease.

Physicians trained primarily to recognize and treat disease are being asked more frequently to quantify impairment of health. Criteria for defining impairment due to chronic obstructive pulmonary diseases are widely accepted, but it has been difficult to establish guidelines for interstitial diseases. To develop and validate criteria, we selected 2,420 patients with airflow obstruction; 821 had interstitial disease, and 938 were employees of asbestos industries. We found that clinical and roentgenographic criteria were inappropriate for defining impairment. The forced vital capacity and single-breath diffusing capacity, each expressed as a percentage of the predicted value, were selected for analysis. Sensitivity studies using response to standard exercise as an independent criterion suggested that the limits reflecting severe impairment were a forced vital capacity 50% of predicted and a single-breath diffusing capacity 40% of predicted. Applying these criteria, 35.6% of patients with interstitial pneumonia, 12.1% with sarcoidosis, and 13.6% with pneumoconioses, but only 1.1% of the workers exposed to asbestos were severely impaired. In more than one half of patients the single-breath diffusing capacity was the only test that indicated severe impairment.

Asbestosis↗
PubMed1979

Bronchiolitis and bronchitis in connective tissue disease. A possible relationship to the use of penicillamine.

Rapid onset of severe and irreversbile airflow obstruction developed in two women. One had eosinophilic fasciitis and the other had rheumatoid arthritis. Both were treated with penicillamine. In the first patient, aged 42 years, dyspnea developed after six months of therapy. Her roentgenogram showed hyperinflation. Forced vital capacity expired in one second (FEV1/FVC%) decreased from 75% to 40%, and the residual volume increased by 1 L. In the second patient, aged 54 years, cough and dyspnea developed after ten months of therapy. The FEV1/FVC% was 56%, the FEV1 was 0.9 L, and the roentgenogram was normal. Lung biopsy specimens demonstrated severe and widespread bronchiolitis. An association between obliterative bronchiolitis and rheumatoid arthritis has been reported. Penicillamine may impair healing of bronchiolitis in such patients.

Adult↗
PubMed1979

Absence of synergism between exposure to asbestos and cigarette smoking in asbestosis.

To assess both independent and synergistic effects of exposure to asbestos and cigarette smoking on the development of asbestosis, survey data from 4 groups of workers exposed to asbestos were analyzed with multivariate statistical models. Survey methods were standardized and included for the 383 subjects a respiratory symptoms questionnaire, occupational history, physical examination, pulmonary function testing, and a chest radiograph. Exposure to asbestos and cigarette smoking were assessed by questionnaire. Synergism between the 2 exposures was not present for previously identified manifestations of asbestosis including bilateral fine crackles, clubbing, dyspnea, radiographic abnormality, decreased forced vital capacity, and decreased single-breath diffusing capacity of the lung for CO. However, additive, independent effects of these 2 exposures were present for each of these parameters.

Adult↗
PubMed1978

Normal chest roentgenograms in chronic diffuse infiltrative lung disease.

We undertook this study to determine the prevalence of normal roentgenograms in chronic diffuse infiltrative lung diseases. Of 458 patients with such disorders histologically confirmed, 44, or 9.6 per cent, had normal pre-biopsy films. In this group with normal x-ray films, desquamative interstitial pneumonia, sarcoidosis and allergic alveolitis were the most frequent diagnoses. Dyspnea was the principal complaint, and fine rales were common. The vital capacity was reduced in 57 per cent, and the single-breath diffusing capacity in 71 per cent. In half, histological changes and functional impairment were moderately severe. Films may be normal in such cases because isolated foci are too small or too few, because diffuse interstitial or intra-alveolar disease may cast no discrete shadows or because the lesions primarily affect airways or blood vessels. Patients with normal chest roentgenograms and normal mechanics of breathing but with impaired gas exchange should have lung biopsy for early diagnosis and therapy.

Adult↗
PubMed1978

Crackles (rales) in the interstitial pulmonary diseases.

There is renewed interest in the classification and methods of recording adventitious pulmonary sounds. This is a study of the importance of fine crackles (rales) in the diagnosis and estimation of the severity of diffuse infiltrative pulmonary disease. Among 272 cases documented by lung biopsy, bilateral fine crackles were heard in 60 percent of those with interstitial pneumonias and asbestosis but in only 20 percent of those with sarcoidosis and other granulomatoses. These incidences were identical in 335 patients diagnosed clinically. In 322 selected ambulatory patients with chronic obstructive pulmonary disease, fine crackles were recorded in only 10 to 12 percent, while coarse crackles were not uncommon in patients with chronic bronchitis. In workers exposed to asbestos, crackles correlated with exposure. In serial studies of such workers, the occurrence of crackles alone appeared to be a random event, while among those with crackles together with one other of five criteria, almost one-half developed asbestosis within four to six years. Fine crackles correlated with pathologic severity, with radiographic honeycombing, and with physiologic abnormalities.

Asbestosis↗
PubMed1975

Isoniazid-associated hepatitis in 114 patients.

Analysis of the overt hepatic disease that developed in 114 patients while taking isoniazid for chemoprophylaxis of tuberculosis showed it to be mainly hepatocellular. The severity of the hepatic injury was manifested by the 13 fatalities (12.3%) and by the histological demonstration of submassive necrosis in 9 and massive necrosis in 4 patients. The 20 other patients from whom hepatic tissue was available for study included 16 with moderately severe acute hepatocellular injury (4 had a mixed hepatocellular-cholestatic pattern), and 4 with chronic hepatic diseases (1 had cirrhosis). Clinical manifestations of hepatic disease prior to the onset of jaundice included vague digestive complaints in 55% of the group and "viral' disease-like complaints in 35%, some with and some without gastrointestinal symptoms. Jaundice was the presenting complaint in 10% of patients. Fever and rash were reported in very few patients (less than 4%) and eosinophilia of modest degree was noted in approximately 10%. Hepatic injury was recognized during the 1st month of isoniazid administration in 15% and during the 2nd month in an additional 31%. In the remaining 54% of patients, the drug had been administered for periods of 2 to 11 months before hepatic injury was noted. Analyses of variables suggested that hepatic injury which presented after 2 months, especially with bilirubin levels that exceeded 20 mg per 100 ml, was more likely to have a fatal outcome than disease that presented during the first 2 months even with higher bilirubin levels. The case fatality rate was significantly higher in black females than in black males or in whites of either sex. The observations of the present study offer no support for the view that isoniazid-induced hepatic disease results from hypersensitivity to the drug. Other data that support the view that hepatotoxic metabolites of isoniazid may be responsible for the injury are considered.

Age Factors↗
PubMedDate not supplied

A radiographic classification for sarcoidosis: physiologic correlation.

The chest roentgenogram is frequently used to judge severity and course of sarcoidosis. The only widely used method for staging, suggested by Siltzbach, does not provide for such judgments. Therefore, we devised a scheme for objective description of type and quantity of opacities based on the ILO/UC Classification for the Pneumoconioses. We added a "reticulonodular" category (x y z) to the present "rounded (p q r) and "linear-irregular" (s t u) categories. We retained the 11 point scale for profusion (severity) and added notations to describe ground glass (alveolar) patterns, size of nodes, and hilar retractions. Among 211 patients, x y z (35%) and p q r (33%) opacities predominated while s t u opacities (19%) were unusual. Radiographic severity correlated best with vital capacity (rs = -0.49) and the diffusing capacity (rs = -0.32). With the Siltzbach classification these correlations were not as good (rs = -0.27 and -0.19). Siltzbach Stage III (fibrosis) was a distinct group with poor function and frequent airway obstruction. There was no correlation between radiographic appearance and pathologic severity because the latter grading, on a scale from 0 to 10, never exceeded 3. Sequential studies in 64 patients showed that, when individuals are used as their own controls, overall profusion correlated highly with physiologic changes over time.

Adult↗