Patterns of improvement in spirometry, bronchial hyperresponsiveness, and specific IgE antibody levels after cessation of exposure in occupational asthma caused by snow-crab processing

Am Rev Respir Dis. 1988 Oct;138(4):807-12. doi: 10.1164/ajrccm/138.4.807.


Thirty-one workers with occupational asthma caused by snow-crab processing were assessed by a long-term follow-up on three occasions at mean +/- SD intervals of 12.8 +/- 5.4, 31.4 +/- 6.3, and 64.4 +/- 6.3 months after leaving work. The diagnosis of work-related asthma was initially confirmed in all of them by specific inhalation challenges at the workplace or by laboratory inhalation of snow-crab boiling water (n = 24) or by serial monitoring of airway caliber and bronchial responsiveness to histamine at work and off work (n = 7). Total duration of work-related exposure was 12.8 +/- 5.6 months (range, 3 to 21 months), and the duration of symptoms after onset was 6.8 +/- 4.2 months (range, 1 to 18 months). At the time of diagnosis, all 31 subjects required medication for asthma, 11 had a FEV1 less than or equal to 85% predicted, and all subjects had a PC20 less than or equal to 16 mg/ml. Twelve of 25 serum samples assessed showed high levels of specific immunoglobulin E (IgE) antibodies to crab meat and/or boiling water. At the time of the first follow-up, there was a reduction in the number of subjects still requiring medication, with a significant reduction in FEV1, and a PC20 less than or equal to 16 mg/ml. However, no further change was observed afterwards. Similarly, the mean FEV1 and FEV1/FVC improved significantly from the time of diagnosis to the first follow-up (p less than 0.01), with a plateau thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Animals
  • Antibodies / analysis*
  • Asthma / etiology*
  • Asthma / physiopathology
  • Brachyura* / immunology
  • Bronchi / physiopathology*
  • Environmental Exposure
  • Female
  • Food-Processing Industry*
  • Forced Expiratory Volume
  • Humans
  • Immunoglobulin E / immunology*
  • Male
  • Spirometry
  • Vital Capacity


  • Antibodies
  • Immunoglobulin E