Efficacy of serial medical surveillance for chronic beryllium disease in a beryllium machining plant.

There is limited information on the use of the blood beryllium lymphocyte proliferation test (BeLPT) at regular intervals in medical surveillance. Employees of a beryllium machining plant were screened with the BeLPT biennially, and new employees were screened within 3 months of hire. Of 235 employees screened from 1995 to 1997, a total of 15 (6.4%) had confirmed abnormal BeLPT results indicating beryllium sensitization; nine of these employees were diagnosed with chronic beryllium disease. Four of the 15 cases were diagnosed within 3 months of first exposure. When 187 of the 235 employees participated in biennial screening in 1997 to 1999, seven more had developed beryllium sensitization or chronic beryllium disease, increasing the overall rate to 9.4% (22 of 235). The blood BeLPT should be used serially in beryllium disease surveillance to capture new or missed cases of sensitization and disease. Beryllium sensitization and chronic beryllium disease can occur within 50 days of first exposure in modern industry.

Observer variation and relationship of computed tomography to severity of beryllium disease.

Although high resolution computed tomography (HRCT) is commonly used to assess interstitial lung disease (ILD), relatively little is known about interrater reliability and construct validity of HRCT-reported nodules, ground-glass opacity, or other typical findings. We determined the interobserver and intraobserver variability of HRCT findings and correlated HRCT abnormalities with physiologic measures in 57 patients with chronic beryllium disease (CBD). Reliability of HRCT scan measurements were assessed using weighted kappa (K(W)) and intraclass correlation coefficients. We correlated HRCT with spirometry, body plethysmographic lung volumes, diffusing capacity for carbon monoxide (DL(CO)), maximal exercise testing with measurement of arterial blood gases, and bronchoalveolar lavage (BAL). Interobserver agreement for three of the HRCT abnormalities found in CBD was moderate: the K(W) for nodules, septal lines, and ground-glass attenuation were 0.53, 0.44, and 0.53, respectively. Agreement was poor for bronchial wall thickening (K(W) = 0.15). HRCT scores correlated significantly with DL(CO), gas exchange at rest and at maximal exercise, and lung volume. This study demonstrates that HRCT has good interrater reliability and correlates with indices of the severity of granulomatous lung diseases such as CBD.

Airway responsiveness and job selection: a study in coal miners and non-mining controls.

BACKGROUND: It has been suggested that health related job selection is a major cause of the healthy worker effect, and may result in inaccurate estimates of health risks of exposures in the working environment. Improved understanding of self selection, including the role of airway hyperresponsiveness, should improve accuracy in estimating occupational risks. METHODS: We evaluated symptoms of the respiratory tract, lung function, occupational and smoking histories, and airway responsiveness from a cross sectional survey of 478 underground bituminous coal miners and non-mining controls. Workers with abnormal spirometry were excluded from methacholine testing. RESULTS: Methacholine responsiveness (> or = 15% decline in forced expiratory volume in one second) was associated in both miners and controls with reduced ventilatory lung function and an increased risk of respiratory symptoms. Miners with the longest duration of work at the coal face had a low prevalence of methacholine responsiveness, compared with miners who had never worked at the coal face (12% v 39%, P < 0.01). Throughout their mining careers, miners who responded to methacholine were consistently less likely to have worked in dusty jobs than miners who did not respond to methacholine. CONCLUSIONS: These results provide evidence that workers who are employed in dusty jobs are less likely than their unexposed coworkers to show increased non-specific airway responsiveness, presumably as a result of health related job selection. Surveys of workers in which responsiveness data are unavailable may underestimate the effects of dust exposure on respiratory health.