Because of the negative results reported in other studies

Occupational exposure is known to cause 15% of asthma cases. The main treatment for occupational asthma is to stop exposure if possible. Although, remission of occupational asthma only occurs in only 30 % of patients after cessation of exposure. There is currently no way of predicting which patients will go into remission after cessation of exposure.

In non-occupational asthma, the inflammatory biomarker T2 has allowed the entry into personalized medicine and can predict future exacerbations.

The investigators hypothesize that T2 biomarkers could be predictive markers for remission in occupational asthma after exposure cessation.

The investigators intend to carry out a follow-up study at the University Hospital of Strasbourg to perform the non-specific bronchial hyperresponsiveness test to assess remission in patients diagnosed with occupational asthma and to compare baseline T2 biomarkers in remission and non remission patients.

Inclusion Criteria:

• Age over 18
• Diagnosis of occupational asthma by specific inhalation challenge
• Exposure to sensitizing agent avoided or reduced
• Able to understand the aims and risks of the research and to give free and informed consent
• For women of childbearing age: effective contraception in progress.
• Benefiting from social security coverage

Exclusion Criteria:

• Impossibility of giving the subject informed information (subject in emergency situation, difficulties in understanding the subject)
• Subject under court protection
• Subject under guardianship or curatorship
• Pregnant or breast-feeding patient