Guest guest Posted August 23, 2005 Report Share Posted August 23, 2005 Be sure to read the NOTE at the bottom. Tobacco Worker's Lung Last Updated: January 21, 2003 Rate this Article Email to a Colleague http://www.emedicine.com/med/topic2282.htm Synonyms and related keywords: hypersensitivity pneumonitis, HP, extrinsic allergic pneumonitis, EAA, TWL, parenchymal lung diseases, tobacco molds AUTHOR INFORMATION Section 1 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Author: Olade, MD, MPH, Fellow, Occupational And Environmental Medicine, Harvard School Of Public Health, Massachusetts General Hospital Coauthor(s): Klaus-Dieter Lessnau, MD, FCCP, Clinical Assistant Professor of Medicine, New York University School of Medicine; Medical Director, Pulmonary Physiology Laboratory, Department of Medicine, Section of Pulmonary Medicine, Lenox Hill Hospital Olade, MD, MPH, is a member of the following medical societies: American College of Occupational and Environmental Medicine, and American College of Physicians Editor(s): Sat Sharma, MD, FRCPC, FACP, FCCP, DABSM, Program Director, Associate Professor, Department of Internal Medicine, Divisions of Pulmonary and Critical Care Medicine, University of Manitoba; Site Coordinator of Respiratory Medicine, St Boniface General Hospital; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Gregg T Anders, DO, Medical Director, Great Plains Regional Medical Command, Brook Army Medical Center; Clinical Associate Professor, Department of Internal Medicine, Division of Pulmonary Disease, University of Texas Health Science Center at San ; D Rice, MD, Associate Professor, Departments of Internal Medicine and Pediatrics and Adolescent Medicine, Saint Louis University School of Medicine; and Zab Mohsenifar, MD, Director, Division of Pulmonary/Critical Care Medicine, Department of Medicine, Cedars-Sinai Medical Center; Professor, Department of Internal Medicine, University of California at Los Angeles School of Medicine Disclosure INTRODUCTION Section 2 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Background: Tobacco worker's lung (TWL) is one disease in the group of parenchymal lung diseases categorized as hypersensitivity pneumonitis (United States) or extrinsic allergic alveolitis (Britain). This disease entity is caused by inhalation of tobacco molds and is encountered in persons who work in tobacco fields and cigarette manufacturing plants. Increased humidity plays a major role in favoring mold growth. The clinical features and natural history are akin to hypersensitivity pneumonitis of other causes. Pathophysiology: Immune mediation plays a major pathogenetic role in TWL. Serum antibodies are present in most patients with TWL, but a lack of correlation between the presence of serum antibodies and pulmonary symptoms has been noted. In TWL, the culprit antigen is the Aspergillus species, with a source in tobacco molds. The antigens induce injury by causing macrophages and polymorphonuclear leukocytes to produce substances such as proteolytic enzymes and reactive oxygen compounds. These further lead to synthesis and release of interleukin (IL)-1, tumor necrosis factor (TNF)-alpha, and IL-6 from macrophages and lymphokines from lymphocytes, which result in pulmonary inflammation. Lung biopsies in patients with long-term exposure usually demonstrate chronic interstitial inflammation and poorly formed nonnecrotizing granulomas. Frequency: In the US: Data are not available. Internationally: Data are not available. Mortality/Morbidity: Because of the excellent prognosis, little documented evidence of long-term illness or death from TWL exists. Sex: Although no documented evidence indicates a sex predilection, TWL is more common in males, probably because most tobacco workers are men. Age: TWL occurs in adults of working age but not in children or retired people. CLINICAL Section 3 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography History: A comprehensive history of exposure to tobacco mold and leaves should be obtained. TWL, as with most hypersensitivity pneumonitis syndromes, has acute, subacute, and chronic presentations. In acute presentations, patients develop abrupt onset of fever, cough, chills, myalgias, headache, and malaise about 4-6 hours following exposure to tobacco plants and molds. These symptoms are self-limited, resolving in 12 hours to several days once the patient avoids the inciting agent. The symptoms may recur with reexposure. Patients who have had long-term exposure to tobacco plantations usually have insidious onset of cough, exertional dyspnea, fatigue, and weight loss. Disabling and irreversible respiratory findings due to pulmonary fibrosis may occur late in the course of the disease. Removing patients from tobacco exposure results in only partial improvement. Physical: Physical examination reveals the following: Tachypnea Diffuse fine rales Wheezing Weight loss Digital clubbing Fever Evidence of cor pulmonale Causes: Major causative antigens include the following: Aspergillus species Scopulariopsis brevicaulis DIFFERENTIALS Section 4 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Chronic Bronchitis Pulmonary Fibrosis, Idiopathic Sarcoidosis Other Problems to be Considered: Inhalation fever (Monday illness) Organic-dust toxic syndrome Allergic bronchopulmonary aspergillosis Pneumoconiosis Bagassosis Byssinosis Quick Find Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Click for related images. Related Articles Chronic Bronchitis Pulmonary Fibrosis, Idiopathic Sarcoidosis Continuing Education CME available for this topic. Click here to take this CME. Patient Education Click here for patient education. WORKUP Section 5 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Lab Studies: No specific tests exist for TWL; the diagnosis is established with a history of exposure and possibly with the support of the following tests. Elevated serum levels of angiotensin-converting enzyme (ACE), N- acetyl-beta-glucosaminidase (NAG), and beta-glucuronidase (beta-GLU) may be present. Elevation of these enzymes does not have a high sensitivity or specificity. Bronchoalveolar lavage (BAL) may show lymphocytosis, neutrophilia or eosinophilia, and reversal of CD4/CD8 ratio. Immunoglobulin (Ig)G, IgM, and IgA serum antibodies to causative antigens may be present. Nonspecific markers of inflammation are elevated. Elevated erythrocyte sedimentation rate Elevated C-reactive protein Positive rheumatoid factor Elevated serum lactate dehydrogenase (LDH) Imaging Studies: Chest radiograph: No distinctive changes are noted on chest radiography, but it might show progressive fibrotic changes associated with upper lobe volume loss or diffuse reticulonodular infiltrates in chronic exposure. In acute exposure, the infiltrates are usually more prevalent in the lower lobes. High-resolution computed tomography (HRCT) scan: This may show a ground-glass appearance, prominent medium-sized bronchial walls, parenchymal micronodules, and absence of hilar adenopathy. Other Tests: Pulmonary function testing shows mostly restrictive patterns with occasionally mixed restrictive and obstructive patterns, impaired diffusion capacity, and lung volume loss. Arterial hypoxemia with hypocapnia reflecting an increased A-a oxygen gradient commonly occurs at rest, with further worsening on exercise. Procedures: Lung biopsies are rarely required to confirm diagnosis because diagnosis is primarily derived from a thorough occupational history, clinical features, and radiography. Both transbronchial and video- assisted thoracoscopic lung biopsy are used to provide adequate specimens for histopathological examination. Histologic Findings: Samples from lung biopsies show chronic interstitial inflammation with infiltration of plasma cells, mast cells, macrophages, and lymphocytes, usually with poorly formed nonnecrotizing granulomas. The granulomas are loosely formed and tend to occur in proximity to the bronchioles. Cholesterol clefts and giant cells also are observed within and outside the granulomas. TREATMENT Section 6 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Medical Care: No medical treatment is available for TWL. The major treatment strategy is elimination of exposure to tobacco molds or leaves. Systemic glucocorticoids have been used to treat patients with TWL but without any good evidence of effectiveness, especially in patients with chronic exposure. Removal from exposure to the offending agents usually leads to symptom resolution. Consultations: Pulmonology MEDICATION Section 7 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography No medications are available. FOLLOW-UP Section 8 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Further Outpatient Care: Patients should receive supportive follow-up care at a chest clinic. Deterrence/Prevention: Avoidance of exposure to tobacco leaves is the best prevention. Complications: Some patients have irreversible lung damage progressing to pulmonary fibrosis with resultant cor pulmonale. Prognosis: The prognosis is excellent if exposure to tobacco plants is curtailed before permanent damage occurs. Patient Education: Inform tobacco workers about the possible risk of chronic lung damage from continuous exposure and that they should seek medical attention if certain symptoms are noted. MISCELLANEOUS Section 9 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Medical/Legal Pitfalls: Medicolegal issues could ensue if the physician fails to recognize the relationship between occupational exposure and symptoms. Workers' compensation usually covers treatment if the exposure was at work. BIBLIOGRAPHY Section 10 of 10 Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Bibliography Bhisey RA, Bagwe AN, Mahimkar MB: Biological monitoring of bidi industry workers occupationally exposed to tobacco. Toxicol Lett 1999; 108: 259-65[Medline]. Ghosh SK, Parikh JR, Gokani VN: Studies on occupational health problems during agricultural operation of Indian workers: a preliminary survey report. J Occup Med 1: 45-7[Medline]. Huuskonen MS, Husman K, Jarvisalo J: Extrinsic allergic alveolitis in the tobacco industry. Br J Ind Med 1984; 1: 77-83[Medline]. Huuskonen MS, Jarvisalo J, Koskinen H: Serum angiotensin-converting enzyme and lysosomal enzymes in tobacco workers. Chest 1986; 2: 224-8 [Medline]. Kusemamariwo T, Neill P: Carcinoma of the bronchus in tobacco farm workers. An unrecognised high risk group. Trop Geogr Med 1990; 3: 261-4[Medline]. NOTE: Medicine is a constantly changing science and not all therapies are clearly established. New research changes drug and treatment therapies daily. The authors, editors, and publisher of this journal have used their best efforts to provide information that is up-to- date and accurate and is generally accepted within medical standards at the time of publication. However, as medical science is constantly changing and human error is always possible, the authors, editors, and publisher or any other party involved with the publication of this article do not warrant the information in this article is accurate or complete, nor are they responsible for omissions or errors in the article or for the results of using this information. The reader should confirm the information in this article from other sources prior to use. In particular, all drug doses, indications, and contraindications should be confirmed in the package insert. FULL DISCLAIMER Tobacco Worker's Lung excerpt Quote Link to comment Share on other sites More sharing options...
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