Abstract | BACKGROUND: The relationship between cough receptor sensitivity and eosinophilic inflammation of the airway in patients with asthma remains unclear. METHODS: Eighteen patients with asthma sensitised to house dust mite (HDM) were enrolled in a randomised parallel group study. Patients with asthma whose main symptom was cough were not enrolled in the study. Half the patients were randomly assigned to inhale saline and the other half to inhale HDM allergen. Cough receptor sensitivity to capsaicin, airway responsiveness to histamine, and sputum eosinophils analysed with hypertonic saline inhalation were investigated before and 24 hours after saline or HDM allergen bronchoprovocation. RESULTS: Patients inhaling saline showed no significant changes in sputum eosinophils (from 7.87% (95% confidence interval (CI) 5.08 to 12.19) to 8.60% (95% CI 3.03 to 14.18); p=0.97), airway responsiveness to histamine (from 726.68 micro g/ml (95% CI 251.90 to 2096.36) to 773.01 micro g/ml (95% CI 251.36 to 2377.23); p=0.96), or capsaicin sensitivity (from 7.23 micro M (95% CI 2.45 to 21.31) to 7.24 micro M (95% CI 2.46 to 21.31); p=0.96). Early asthmatic response was induced in all patients, and late asthmatic response was observed in six of nine patients inhaling HDM allergen. Although there were significant increases in sputum eosinophils (from 9.83% (95% CI 6.78 to 14.27) to 21.00% (95% CI 13.85 to 28.15); p<0.01) and airway responsiveness to histamine (from 784.16 micro g/ml (95% CI 318.24 to 1932.24) to 377.81 micro g/ml (95% CI 118.43 to 1205.24); p<0.05) 24 hours after HDM allergen inhalation compared with baseline levels, capsaicin sensitivity did not change significantly (from 5.75 micro M (95% CI 1.91 to 17.30) to 6.20 micro M (95% CI 2.21 to 17.38); p=0.77). CONCLUSIONS:
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Authors | H Minoguchi, K Minoguchi, A Tanaka, H Matsuo, N Kihara, M Adachi |
Journal | Thorax
(Thorax)
Vol. 58
Issue 1
Pg. 19-22
(Jan 2003)
ISSN: 0040-6376 [Print] England |
PMID | 12511713
(Publication Type: Clinical Trial, Journal Article, Randomized Controlled Trial)
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Chemical References |
- Allergens
- Dust
- Sodium Chloride
- Capsaicin
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Topics |
- Adult
- Allergens
(pharmacology)
- Asthma
(physiopathology)
- Bronchi
(physiology)
- Bronchial Provocation Tests
- Bronchitis
(physiopathology)
- Capsaicin
- Cough
(physiopathology)
- Dust
- Eosinophils
(physiology)
- Female
- Forced Expiratory Volume
(physiology)
- Humans
- Male
- Sensory Receptor Cells
(physiology)
- Sodium Chloride
(pharmacology)
- Sputum
(cytology)
- Vital Capacity
(physiology)
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