The Role of the Nasal Allergen Provocation Test in Starting and Monitoring Allergen Immunotherapy

• AIT (Drug): AIT for airborn allergens (SCIT/SLIT)
• NAPT (Diagnostic test): NAPT test with airborn allergens ( HDM, Threes, Grasses)

Primary outcomes

• The effectiveness of AIT treatment assessed by the change in the blood concentration in total en specific IgE . [before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing blood results, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up).
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the Lebelscore. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing the Lebelscores ,assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). Lebelscore has a range between 0 and 12.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the SNOT-22. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing SNOT-22, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). SNOT-22 is sino-nasal outcome test with 22 items which ranges from 0 to 110.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the VAS. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing VAS, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). The visual analogue scale (VAS) ranges from 0 to 10cm for every item.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the TNSS. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing TNSS, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). Total nasal symptom score (TNSS) ranges from 0 to 12.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the ACT. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing ACT, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). ACT is the Asthma control test with scores between 0 and 25. The higher the score the better.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the RQLQ. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing RQLQ, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). RQLQ is the rhinoconjunctivits quality of life questionnaire with scores between 0 and 168. The higher the score of these questionnaires the more discomfort.
• The effectiveness of AIT treatment assessed by the change in quality of life meassured by the TRE. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing TRE, assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). TRE is the therapeutic response evaluation and will be scored between 'much better' and 'much worse'.
• The effectiveness of AIT treatment assessed by the change in the PNIF value. [Before start AIT, every 6 months en after 3 years]: The effectiveness of AIT treatment will be analysed by comparing PNIF values assessed by the NAPT tests, before, during (every 6 months after starting AIT) and after end of treatment (approximately 3 years after start-up). PNIF is the peak nasal inspiratory flow with a value between 0 and 370 l/min). The higher the value the less congested the nose is.

Secondary outcomes

• Calculating the cost savings by desensitizing poly-sensitized patients only to the allergen to which they respond most strongly in the NAPT test. [3 years]
• Calculating the cost savings by timely stopping AIT treatment in non-responders, which we can define as patients who do not experience subjective or objective improvement after 1 year of treatment. [3 year]

Sex: All, ages: 18 Years to 60 Years

Inclusion Criteria:

* Age >18 and ≤60 years
* Persistent or intermittent allergic rhinitis complaints, confirmed by SPT and/of immunocap for the specific IgEs.

OR suspected local allergic rhinitis

* Patients who start with AIT treatment
* The patient must be motivated and willing to come to all visits
* The patient must be able to understand and sign the informed consent

Exclusion Criteria:

* Uncontrolled asthma
* Conditions affecting the functioning of the immune system (eg: immune deficiencies, malignancies, autoimmune diseases)
* Use of β-blockers, immunosuppressants or ACE inhibitors
* Hypersensitivity to aluminum hydroxide and/or hypersensitivity to any of the excipients in AIT
* Anaphylaxis after allergen challenge in the past
* Acute rhinosinusitis in the last 12 weeks
* Recent surgery on the nose and/or paranasal sinuses in the last 12 weeks
* Pregnancy