Hypersensitivity pneumonitis (extrinsic allergic alveolitis) induced by isocyanates.

Abstract

BACKGROUND:

Chemical-induced hypersensitivity pneumonitis has been so far rarely described. The purpose of this study was to find out whether hypersensitivity pneumonitis is a common disorder in isocyanate workers.

METHODS:

Company physicians' case histories of 1780 isocyanate workers were evaluated. In 16 subjects suspected of having isocyanate-induced hypersensitivity pneumonitis, chest x-ray films were made; levels of IgE and IgG antibodies to isocyanate-human serum albumin were estimated; conjugates and isocyanate challenge tests, bronchoalveolar lavage fluid analyses, and/or lung histologic investigations were performed.

RESULTS:

Each of the 14 study patients who had hypersensitivity pneumonitis had work-related dyspnea and fever occurring several hours after the start of work with isocyanates. Typical clinical findings were the reduction of lung diffusing capacity (n = 10), reticular or nodular lung patterns in the x-ray film (n = 9), and serum IgG antibodies specific to isocyanate-human serum albumin conjugates (n = 10). Restrictive ventilation patterns in the inhalation challenge tests (n = 5), lymphocytic and/or neutrophilic alveolitis seen in bronchoalveolar lavage fluid analyses (n = 7), and lymphohistiocytic patterns mostly associated with mild fibrosis in lung histology (n = 5) confirmed the diagnosis.

CONCLUSIONS:

Occupational exposure to isocyanate vapors and aerosols induces typical hypersensitivity pneumonitis in at least 1% of the isocyanate workers with symptoms. Diphenylmethane diisocyanate was found to be the main cause of this disorder.

• Authors: X Baur
• Journal: The Journal of allergy and clinical immunology (J Allergy Clin Immunol) Vol. 95 Issue 5 Pt 1 Pg. 1004-10 (May 1995) ISSN: 0091-6749 [Print] United States
• PMID: 7751497 (Publication Type: Journal Article)

Chemical References

• Allergens
• Immunoglobulin G
• Isocyanates
• 4,4'-diphenylmethane diisocyanate

Topics

• Adolescent
• Adult
• Allergens (adverse effects, immunology)
• Alveolitis, Extrinsic Allergic (etiology)
• Antibody Specificity
• Biopsy
• Bronchoalveolar Lavage Fluid (cytology)
• Bronchoscopy
• Chemical Industry
• Female
• Humans
• Immunoglobulin G (blood, immunology)
• Isocyanates (adverse effects, immunology)
• Lung (pathology)
• Male
• Middle Aged
• Occupational Exposure
• Radiography, Thoracic
• Respiratory Mechanics