Antileukotrienes in rhinosinusitis and nasal polyposis

AERD Associated Nasal Polyposis: Efficacy of Postoperative Antileukotriene Therapy in Comparison with Aspirin Desensitization. A Retrospective Study

INTRODUCTION

AERD (aspirin-exacerbated respiratory disease) is a severe form of an inflammatory disease of the upper airway system. Therapy remains challenging due to a complex underlying pathophysiology.

OBJECTIVE

To evaluate the efficacy of postoperative antileukotriene therapy concerning recurrence of nasal polyposis in patients with AERD and to compare it with AD (aspirin desensitization) over time.

METHODS

In this retrospective study we analyzed AERD patients (N = 61) after functional endoscopic sinus surgery (FESS). Patients were treated at our institution postoperatively with topical mometasone (control group, N = 22), leukotriene-receptor-antagonists (montelukast [MT], N = 18) or underwent an aspirin desensitization (N = 21). Subjective parameters as assessed by SNOT (sinonasal outcome test) questionnaire and endoscopic endonasal examination (polyposis grading) were evaluated throughout a follow-up period of 6-9 and >12 (long-term) months after surgery.

RESULTS

Endoscopic endonasal examinations 6-9 months after sinus surgery showed a good disease control in all 3 groups with significant reduction in polyp grading in the AD group. After a follow-up period of more than 12 months, MT and AD patients had significantly less polyp recurrences as compared to the topical treatment group. Subjective sinonasal symptoms revealed that hyposmia and nasal obstruction were prominent factors in all 3 groups throughout the follow-up period. MT group showed significant improvement in sinonasal symptoms over time.

CONCLUSION

Postoperative treatment with leukotriene-receptor-antagonists and aspirin desensitization both significantly reduce nasal polyp recurrence. MT has a positive effect on subjective sinonasal outcomes and patients' quality of life over time.

Efficacy of Montelukast as Prophylactic Treatment for Seasonal Allergic Rhinitis

The evidence supporting the prophylactic treatment of seasonal allergic rhinitis before the start of pollen dispersal is still lacking. We conducted a study to investigate the efficacy of prophylaxis with montelukast for seasonal allergic rhinitis and to evaluate its influence on the inflammatory condition of the lower airway. Our final study population was made up of 57 adults who were randomized to a prophylactic treatment group and a control group. The prophylaxis group was made up of 31 patients—10 men and 21 women, aged 18 to 54 years (mean: 36.9)—who were administered montelukast for 2 weeks before the cypress pollen season and subsequently throughout the remainder of the season. The control group was made up of 26 patients—11 men and 15 women, aged 24 to 63 years (mean: 39.2)—who took montelukast during the pollen season only. During the pollen season, the mean daily rescue medication score was significantly lower in the prophylaxis group (3.22 vs. 3.89; p = 0.001). However, there was no statistical difference in the two groups’ mean daily rhinoconjunctivitis symptom scores. Also, the fraction of exhaled nitric oxide in the prophylaxis group tended to be lower than that of control group, but again the difference was not significant (29.8 vs. 42.1 ppb; p = 0.189). We conclude that antileukotriene prophylaxis started 2 weeks before the cypress pollen dispersal was effective in reducing the need for rescue medication during the pollen season and showed a trend toward alleviating the eosinophilic inflammation in the lower airway induced by the pollen.

Antileukotrienes in upper airway inflammatory diseases

Leukotrienes (LTs) are a family of inflammatory mediators including LTA4, LTB4, LTC4, LTD4, and LTE4. By competitive binding to the cysteinyl LT1 (CysLT1) receptor, LT receptor antagonist drugs, such as montelukast, zafirlukast, and pranlukast, block the effects of CysLTs, improving the symptoms of some chronic respiratory diseases, particularly bronchial asthma and allergic rhinitis. We reviewed the efficacy of antileukotrienes in upper airway inflammatory diseases. An update on the use of antileukotrienes in upper airway diseases in children and adults is presented with a detailed literature survey. Data on LTs, antileukotrienes, and antileukotrienes in chronic rhinosinusitis and nasal polyps, asthma, and allergic rhinitis are presented. Antileukotriene drugs are classified into two groups: CysLT receptor antagonists (zafirlukast, pranlukast, and montelukast) and LT synthesis inhibitors (5-lipoxygenase inhibitors such as zileuton, ZD2138, Bay X 1005, and MK-0591). CysLTs have important proinflammatory and profibrotic effects that contribute to the extensive hyperplastic rhinosinusitis and nasal polyposis (NP) that characterise these disorders. Patients who receive zafirlukast or zileuton tend to show objective improvements in, or at least stabilisation of, NP. Montelukast treatment may lead to clinical subjective improvement in NP. Montelukast treatment after sinus surgery can lead to a significant reduction in eosinophilic cationic protein levels in serum, with a beneficial effect on nasal and pulmonary symptoms and less impact in NP. Combined inhaled corticosteroids and long-acting β-agonists treatments are most effective for preventing exacerbations among paediatric asthma patients. Treatments with medium- or high-dose inhaled corticosteroids, combined inhaled corticosteroids and LT receptor antagonists, and low-dose inhaled corticosteroids have been reported to be equally effective. Antileukotrienes have also been reported to be effective for allergic rhinitis.

Expression of leukotriene and its receptors in eosinophilic chronic rhinosinusitis with nasal polyps

BACKGROUND

Cysteinyl leukotriene (LT) has been proposed in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). This study sought to examine the expression of the LT receptor (LTR) in CRSwNP patients and evaluate the potential role of LTR antagonist (LTRA) in the management of eosinophilic CRSwNP (ECRS) patients.

METHODS

Nasal polyps and uncinate process tissues were collected from 18 ECRS patients, 13 non-eosinophilic CRSwNP (non-ECRS) patients, and 16 control subjects. The messenger RNA (mRNA) and protein expression of LTR (cysteinyl leukotriene receptor 1 [CysLT1R] and cysteinyl leukotriene receptor 2 [CysLT2R]) was examined using quantitative reverse-transcription polymerase chain reaction (qRT-PCR), immunohistochemistry, and Western blot analysis. Moreover, the effects of LTRA and steroids on total nasal symptom scores (TNSS) of uncontrolled ECRS patients were evaluated.

RESULTS

The mRNA and protein expression of CysLT1R and CysLT2R was significantly increased in polyp tissues compared with healthy controls (p < 0.05). Compared with the non-ECRS subset, the ECRS subset showed significantly increased expression of CysLT1R and CysLT2R, as well as leukotriene C4 (LTC4) and leukotriene D4 (LTC4) levels (p < 0.05). Moreover, combined LTRA and steroids significantly decreased TNSS more than steroids alone in uncontrolled ECRS patients (p < 0.01).

CONCLUSION

Our findings indicate that LTR was differentially expressed between ECRS and non-ECRS patients, and that LTRA may be used as an additional therapy for ECRS patients.

Actual concepts in rhinosinusitis: a review of clinical presentations, inflammatory pathways, cytokine profiles, remodeling, and management

Rhinosinusitis (RS) is a heterogeneous group of diseases. It is a significant and increasing health problem that affects about 15% of the population in Western countries. It has a substantial impact on patients' health-related quality of life and daily functioning and represents a huge financial burden to society and the health care system as a result of the direct and indirect costs. In addition, RS is not well-understood, and little is known about the etiology and pathophysiology. In the past decade, many papers have been published that have changed our understanding of RS. RS is commonly classified into acute and chronic RS based on symptom duration. In acute RS, an inflammatory reaction initiated by a viral infection characterizes most uncomplicated, mild to moderate cases. Therefore, the first line of treatment for these cases are intranasal steroids and not antibiotics. In severe and complicated cases, antibiotics combined with topical steroids remain the treatment of choice. On the other hand, chronic RS is actually subdivided into two distinct entities (chronic rhinosinusitis with and without polyps), as growing evidence indicates that these entities have specific inflammatory pathways and cytokine profiles. The authors review recent data regarding the clinical presentations, cytokine profiles, tissue remodeling, and modalities of treatment for each form of RS.