Allergic Rhinitis, Asthma
Conditions
Keywords
Leukotriene D4, allergic rhinitis, nasal airway resistance, nasal provocation test, nasal hyperreactivity, airway inflammation, asthma
Brief summary
Leukotrienes play critical roles in the inflammatory process in allergic rhinitis and bronchial asthma, therefore, anti-leukotriene therapy is part of treatment for asthma. However, not all allergic rhinitis accompanied with or without asthma treated with anti-leukotriene were effective. So it is critical to develop a method to identify the response subgroup. In this study, it is assumed that nasal physiological responsiveness to leukotriene nasal provocation test (NPT) is able to gain evidence on the effect of leukotriene on the development of allergic rhinitis and asthma, and is helpful to the use of anti-leukotriene agent. The purpose of the study is to establish the methodology and diagnostic value of leukotriene D4 (LTD4) nasal provocation.
Detailed description
Nasal provocation test induced by LTD4 will be conducted by measuring nasal airway resistance and airway symptoms in a stepwise concentration of LTD4 by nasal spray. Inflammation biomarkers, such as eosinophilic granulocyte in sputum and nasal lavage, fractional exhaled nitric oxide(FeNO), and lung function before and after nasal provocation will be studied to explore the impact of LTD4 nasal provocation test on airway inflammation.
Interventions
DRUGleukotriene D4
Nasal challenge using 16% ethanol diluent, the concentration of which corresponded to the highest concentration of LTD4, was undertaken for exclusion of subjects hypersensitive to ethanol or saline. The LTD4 challenge could be initiated provided that NAR increase was \<30%. Ranges of 4 to 16 mcg.mL-1 LTD4 diluents were applied for a double-fold increment approach at intervals of 6 minutes.
DRUGhistamine
Nasal challenge using 0.9% saline, was undertaken for exclusion of subjects hypersensitive to saline. The histamine nasal challenge could be initiated provided that NAR increase was \<30%. Ranges of 0.4 to 3.2 mg.mL-1 histamine diluents were applied for a double-fold increment approach at intervals of 3 minutes.
Sponsors
Guangzhou Institute of Respiratory Disease
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients with allergic rhinitis accompanied with or without asthma * positive skin prick test (SPT) * had no acute upper or lower airway infection 2 weeks prior to study * no oral or nasal anti-histamines * no leukotriene receptor antagonists for 1 week * no oral or nasal and inhaled corticosteroids for 2 weeks
Exclusion criteria
* smokers * a past confirmed history of chronic respiratory disease other than asthma * other severe systemic diseases (myocardial infarction, malignant tumor, etc.) * under immunotherapy * unable to complete the test or had limited understanding * pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of participants positive response to leukotriene D4 or histamine nasal provocation test | Until 1 hour after the nasal provocation test | Nasal airway resistance measured by positive anterior rhinomanometry. Concentration induced 60% increase of nasal airway resistance (PC60-NAR) will be measured and reported; Composite symptoms score defined by reichmann H and his colleagues showed as follows:3-5 sneezes = 1 point (pt), \>5 sneezes = 2 points (pts); rhinorrhoea \< 1 milliliter (mL) = 1 pt, rhinorrhoea \> 1 milliliter = 2 pts; pruritus of the palate or ear or eye= 1 pt, conjunctivitis or cough or urticaria or difficult breathing= 2 pts. Total score ranges from 0 to 6 pts. Positive response to LTD4 nasal provocation test was defined as PC60-NAR less than 16mcg/mL or the symptom score higher than 3. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from baseline of eosinophils in sputum and nasal lavage and fractional exhaled nitric oxide (FeNO) | 4 and 24 hours after the nasal provocation test | Biomarkers in upper and lower airways such as eosinophils in sputum and nasal lavage and fractional exhaled nitric oxide (FeNO) will be studied. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Change from baseline of cumulative dosage of methacholine causing a 20% fall in forced expiratory volume in 1 second (PD20FEV1-MCH) | Half an hour after nasal provocation test | The increase of brochial hyperresponsiveness induced by nasal provocation test was assessed by the decrease of cumulative dosage of methacholine causing a 20% fall in forced expiratory volume in 1 second (PD20FEV1-MCH). |
| Peak Nasal Inspiratory Flow (PNIF) | 3 minutes after each concentration of provocation agent administrated into the nostrils | The peak nasal inspiratory flow (PNIF) is measured by PNIF meter (in-check dial, Clement Clarke International Ltd.); Change from baseline of peak nasal inspiratory flow (PNIF) at the end of nasal provocation test will be reported. |
Countries
China
Outcome results
None listed