Leukotriene C4 Synthase A-444C Gene Polymorphism in Patients with Allergic Rhinitis

OBJECTIVE: To determine the frequency of leukotriene C4 synthase A-444C polymorphism in allergic rhinitis patients.

STUDY DESIGN AND SETTING: A prospective, randomized, case-controlled study. Blood samples were obtained from 85 patients with allergic rhinitis and 95 healthy individuals. After the extraction of DNA from the blood samples, the leukotriene C4 synthase A-444C polymorphism was studied by a real-time polymerase chain reaction method.

RESULTS: The AC and CC genotype frequencies were statistically higher in the study group ( P = 0.048 and P = 0.037, respectively). In addition, the AC polymorphism carried an increased risk of developing allergic rhinitis (odds ratio = 2.18, 95% confidence interval, 1.173–4.053, P = 0.014).

CONCLUSION: The C allele of the leukotriene C4 synthase gene increases the risk of developing allergic rhinitis.

SIGNIFICANCE: The leukotriene C4 synthase A-444C gene polymorphism is important in susceptibility to allergic rhinitis and this is the first study of this gene polymorphism in allergic rhinitis.

BSACI guidelines for the management of allergic and non-allergic rhinitis

This guidance for the management of patients with allergic and non-allergic rhinitis has been prepared by the Standards of Care Committee (SOCC) of the British Society for Allergy and Clinical Immunology (BSACI). The guideline is based on evidence as well as on expert opinion and is for use by both adult physicians and paediatricians practicing in allergy. The recommendations are evidence graded. During the development of these guidelines, all BSACI members were included in the consultation process using a web-based system. Their comments and suggestions were carefully considered by the SOCC. Where evidence was lacking, consensus was reached by the experts on the committee. Included in this guideline are clinical classification of rhinitis, aetiology, diagnosis, investigations and management including subcutaneous and sublingual immunotherapy. There are also special sections for children, co-morbid associations and pregnancy. Finally, we have made recommendations for potential areas of future research.

Turkish physicians' perception of allergic rhinitis and its impact on asthma

BACKGROUND

The clinical association of rhinitis and asthma has been recognized for centuries, leading to a current definition of 'one airway, one disease'. Current findings indicate that the optimal treatment of rhinitis might improve coexisting asthma.

OBJECTIVES

To evaluate perception of the asthma-rhinitis association and to determine their capability in managing rhinitis.

METHODS

Participants of three national asthma meetings, in 2004, were asked to complete a questionnaire which, aside from demographic queries, elicited responses in order to reflect agreement or not with the given statements.

RESULTS

Of the 354 attendees, 220 (62%) responded to the questionnaire. Although over 80% reported good perception of the asthma-rhinitis association, only one-third were examining nasal mucosa of asthmatics, and over 70% believed sinus X-ray, blood eosinophil count, and determination of total serum IgE were required to diagnose allergic rhinitis. Between 20% and 40% of the physicians reported misuse of medications for rhinitis.

CONCLUSIONS

This survey documented that the asthma-rhinitis association is generally recognized by physicians treating asthma in Turkey. However, there are certain training needs in terms of attitude towards examinations and appropriate use of laboratories and medications for rhinitis. Improved understanding/management of rhinitis may contribute to asthma care as well as patient satisfaction and adherence to treatment.

Protective effect of montelukast on lower and upper respiratory tract responses to short-term cat allergen exposure

BACKGROUND

Challenge with short-term exposure to airborne cat allergen in sensitized patients produces pulmonary function changes and rhinitis symptoms.

OBJECTIVE

To determine the benefit of montelukast, 10 mg, for patients with concomitant asthma and allergic rhinitis as demonstrated by protection against both lower and upper airway responses to cat allergen challenge.

METHODS

This randomized, crossover study treated patients with montelukast vs placebo during two 2-week, double-blind treatment periods, separated by a 1-week washout period. After each treatment period, patients underwent a 60-minute or less exposure to high levels of airborne cat allergen. Lower and upper airway responses were measured by spirometry and symptom scores.

RESULTS

Of 52 patients with data from both treatment arms, 79% of patients taking montelukast and 67% taking placebo were exposed to the full 60-minute allergen challenge. Montelukast provided significant (P < or = .001) protection against allergen challenge in the lower airway coprimary end point of area under the curve during challenge (AUC0-60min) for percentage decrease in forced expiratory volume in 1 second: mean of 10.5% per hour and 14.7% per hour for montelukast and placebo, respectively. Although the effect on the overall nasal symptoms score (NSS) coprimary end point of AUC0-60min was not statistically significance (P = .12), nasal congestion during the challenge and NSS during recovery showed statistically significant (P = .048) protection by montelukast. Additional analyses of simultaneous lower and upper airway responses showed that more patients taking montelukast (22, 43%) vs placebo (13, 26%) were protected from both asthma and rhinitis (P = .02), with an odds ratio of 2.24 (95% CI, 1.16-4.32) in favor of montelukast.

CONCLUSIONS

Montelukast has a protective effect against both lower and upper airway responses during exposure to high levels of cat allergen.

The effect of montelukast on rhinitis symptoms in patients with asthma and seasonal allergic rhinitis

OBJECTIVE

The objective of this study was to evaluate montelukast 10 mg daily as treatment for allergic rhinitis in patients with symptomatic allergic rhinitis and active asthma during the allergy season.

METHODS

This was a multicenter study of 831 patients (ages 15 years-85 years) with seasonal allergen sensitivity, active symptoms of seasonal allergic rhinitis, and active asthma. Following a single-blind, placebo run-in period of 3 days-5 days, patients were randomized to oral montelukast 10 mg (n = 415) or placebo (n = 416) daily during the 2-week, double-blind, active-treatment period.

MAIN OUTCOME MEASURES

The primary endpoint was Daily Rhinitis Symptoms score, average of Daytime Nasal Symptoms and Nighttime Symptoms, as self-rated by patients on a 0-3 scale on daily diaries.

RESULTS

Montelukast reduced the Daily Rhinitis Symptoms score: difference between montelukast and placebo in mean change from baseline was -0.12 [95% CI -0.18, -0.06; p < or = 0.001]. Similar improvements were seen in Daytime Nasal Symptoms (-0.14 [-0.21, -0.07; p < or = 0.001]) and Nighttime Symptoms (-0.10 [-0.16, -0.04; p < or = 0.001]). Improvements (p < 0.05) were seen in Daytime Eye Symptoms and in the secondary endpoints of Global Evaluations of AR by Patient and by Physician, and Rhinoconjunctivitis Quality of Life. In exploratory analyses, improvement in rhinitis symptoms was numerically (though not statistically) larger in patients with greater levels of asthma at study start. Montelukast provided benefit in the Global Evaluations of Asthma by Patient and by Physician: mean differences were -0.24 [-0.41, -0.06; p = 0.008] and -0.17 [-0.33, -0.01; p = 0.037]. Similarly, as-needed beta-agonist use (puffs/day) was reduced with montelukast (p < or = 0.005).

CONCLUSION

Montelukast provides significant relief from symptoms of seasonal allergic rhinitis, while also conferring a benefit for asthma, in patients with both allergic rhinitis and asthma.