The efficacy of montelukast and airway mast cell profiles in patients with cough variant asthma.
BACKGROUND
Cough variant asthma (CVA) is characterized by chronic cough without apparent wheezing; its pathophysiology is considered to be similar to that of classic asthma.


OBJECTIVE
The clinical effects of montelukast, a cysteinyl-leukotriene receptor antagonist, on cough variant asthma were assessed, and the activation profile of airway mast cells was examined.


METHODS
Montelukast (10 mg/day) was given orally to 36 CVA patients (25 women and 11 men; median age, 37.5 years). Before treatment, the patients' bronchial mucosa underwent a biopsy with a fiberoptic bronchoscope. The biopsy specimens were double stained with anti-CD63 antibody and anti-human tryptase antibody.


RESULTS
After 2 weeks of montelukast treatment, cough symptoms improved in 22 patients (the effective group) but did not improve in 14 patients (the ineffective group); in the ineffective group, the symptoms disappeared 2 weeks after they were switched to fluticasone propionate (400 microg/day) inhalation therapy. In the effective group, the time interval from the onset of symptoms to the initiation of treatment was significantly shorter than in the ineffective group. The bronchial mucosa biopsy specimens showed that the proportion of CD63-positive cells in tryptase-positive mast cells was significantly higher in the effective group than in the ineffective group; although the total numbers of mast cells were not different between the two groups.


CONCLUSIONS
There is a subgroup of CVA patients in whom leukotrienes are closely involved in the pathogenesis of their chronic cough; activation of airway mast cells may be an essential feature in these patients.
Kawai
Seiko
S
Division of Respiratory Medicine and Allergology, Department of Internal Medicine, Aichi Medical University School of Medicine, Aichi, Japan.
Baba
Kenji
K
Matsubara
Ayako
A
Shiono
Hiroyuki
H
Okada
Tadashi
T
Yamaguchi
Etsuro
E
D000085:Acetates / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D018927:Anti-Asthmatic Agents / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology; D001491:Basophils / Q000276:immunology; D003371:Cough / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology; D003521:Cyclopropanes; D004804:Eosinophils / Q000276:immunology; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007958:Leukocyte Count; D020024:Leukotriene Antagonists / Q000627:therapeutic use*; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D008875:Middle Aged; D011804:Quinolines / Q000627:therapeutic use*; D020545:Respiratory Mucosa / Q000166:cytology / Q000276:immunology; D013440:Sulfides; D016896:Treatment Outcome
D000085:Acetates; D018927:Anti-Asthmatic Agents; D003521:Cyclopropanes; D020024:Leukotriene Antagonists; D011804:Quinolines; D013440:Sulfides; D007073:Immunoglobulin E; C093875:montelukast