In its first official statement since 1986 on the topic, the American Thoracic Society (ATS) has published a document entitled "Diagnosis and Initial Management of Nonmalignant Diseases Related to Asbestos." The revised statement, updated and reviewed by an 11-person committee of experts, appears in the second issue for September 2004 of the ATS peer-reviewed American Journal of Respiratory and Critical Care Medicine. According to the authors, the new statement is designed to provide guidance to clinicians in the diagnosis of nonmalignant asbestos-related disease. The nonmalignant medical conditions covered, which are associated with breathing the mineral dust, include: asbestosis, a chronic, progressive lung disease often marked by scarring (fibrosis) of the lung tissue; pleural plaques and more diffuse forms of pleural thickening; benign or nonmalignant pleural effusions (the abnormal collection of fluid in the pleural space); and airway obstruction. (The pleura is the delicate membrane covering the lungs and the inner walls of the chest.) In the late 19th century, industry recognized that commercial asbestos had high tensile strength, flexibility, resistance to chemical and thermal degradation, and high electrical resistance. Because of these qualities, asbestos was widely used in the past for insulation, brake linings, flooring, cement, paint, textiles, and various other products. However, after documentation of its hazards in the 1970s and 1980s, use of asbestos fell rapidly, and the industrial mineral was ultimately banned in many western countries. When asbestos-related illness is suspected by a physician, the document advises the doctor to take a comprehensive occupational and environmental history, with emphasis on exposure 15 years or more prior to the current office visit. The report estimates that asbestos is still a hazard for 1.3 million workers in the construction industry in the United States and for workers involved in the maintenance of buildings and equipment. Although the majority of products containing asbestos are older versions, new products that may contain the industrial mineral include brake pads, roofing materials, vinyl tiles, and imported cement pipe and sheeting. According to the experts, a chest X-ray is an extremely useful tool to aid in the diagnosis of asbestos-related pleural disease (fluid in the pleural spaces). In addition, the report notes: "The specificity of the diagnosis of asbestosis increases with the number of consistent findings on chest film, the number of clinical features present (symptoms, signs, and pulmonary function changes), and the significance and strength of the history of exposure." However, according to the document, once exposure to asbestos has occurred, no prophylactic medication or treatment is currently available to prevent the development or the progression of asbestosis or other asbestos-related diseases. Treatment is often designed to ease symptoms.
REDUCING EOSINOPHILIC AIRWAY INFLAMMATION IN SEVERE ASTHMA
In a study of patients with severe asthma who had eosinophils in their sputum despite extensive anti-asthma medication, investigators showed that a high dose of extra intra-muscular corticosteroids resulted in almost complete disappearance of eosinophilic cells, led to decreased use of "rescue" medications by treated patients, and helped to improve the individual's lung function tests. (Eosinophils are a type of white blood cell that constitutes from 1 to 3 percent of total white cell count and functions in allergic or inflammatory responses.) The researchers studied 22 non-smoking outpatients with severe asthma in order to prove that patients with extensive eosinophilia, despite significant anti-inflammatory treatment, were sensitive to high dose injected corticosteroids. Of the 22 patients in the study, 11 received injected steroids and 11 were given placebo over a 3-week period. All patients had sputum eosinophilia above the upper limit of normal. However, after treatment with injected corticosteroids, sputum eosinophils returned to normal levels (from zero to 2 percent) in the 11 treated patients. The researchers believe that levels of symptoms and lung function can, and should be, improved by intensifying treatment and/or administering corticosteroids via the systemic route. They point out that injecting these drugs might help reach regions of the airways that are not accessible to inhaled corticosteroids. The 22 nonsmoking patients who had severe bronchial asthma were between the ages of 21 and 73; 15 of the group were women. The research appears in the second issue for September 2004 of the ATS peer-reviewed American Journal of Respiratory and Critical Care Medicine.
For the complete text of these articles, please see the American Thoracic Society Online Web Site at http//www.atsjournals.org. For either contact information or to request a complimentary journalist subscription to ATS journals online, or if you would like to add your name to the Society's twice monthly journal news e-mail list, contact Cathy Carlomagno at (212) 315-6442, or by e-mail at ccarlomagno@thoracic.org
Journal
American Journal of Respiratory and Critical Care Medicine