The role of leukotrienes in nasal allergy

An Update on Nonsteroidal Anti-Inflammatory Drug-Induced Urticaria

BACKGROUND

Hypersensitivity reactions to non-steroidal anti-inflammatory drugs (HR-NSAIDs) are common adverse events related to the widespread use of over-the-counter NSAIDs for the treatment of a variety of inflammatory conditions. Urticaria is the most commonly reported immediate cutaneous clinical sign of HR-NSAIDs, but it can be a manifestation of pathophysiologically different clinical entities that require different therapeutic strategies. The aim of this study is to ease the identification of the correct phenotype of HR-NSAIDs in patients reporting urticaria associated with the intake of NSAIDs and provide updated information about their diagnosis and management.

METHODS

The study is a narrative review conducted by collecting the most relevant and up-todate data related to the classification, pathophysiology, severity, and prognosis of NSAID hypersensitivity reactions. PubMed and Embase scientific databases were used as search engines to select relevant articles.

RESULTS

Patients developing HR-NSAIDs can be divided into two categories: selective responders (SR), who develop reactions after the administration of a single specific NSAID due to an underlying IgE or T-cell mediated hypersensitivity mechanism, or cross-intolerant (CI), who develop reactions to more than one chemically unrelated NSAIDs due to abnormalities in the biochemical pathways related with prostaglandin metabolism, independently from an underlying immunological mechanism. Five major different categories of HR-NSAIDs have been identified: NSAIDs-exacerbated cutaneous disease (NECD), NSAIDs-induced urticaria/angioedema with/without respiratory and systemic symptoms of anaphylaxis (NIUAA), and NSAIDsexacerbated respiratory disease (NERD), which are developed by CI patients, and single NSAIDs-induced urticaria, angioedema and/ or anaphylaxis (SNIUAA) and single NSAIDsinduced delayed hypersensitivity reactions (SNIDHR), which are developed by CI patients. In vivo and in vitro diagnostic tests have rarely been shown to be reliable in all these entities and therefore are not routinely used in clinical practice. The management in SR patients consists of strict avoidance of the culprit drug, while for cross-intolerance reactions oral tolerance tests with safe alternative drugs (e.g. weak COX-1 inhibitors or selective COX-2 inhibitors) can be performed.

CONCLUSION

HR-NSAIDs are being observed with increasing frequency, however, the pathogenesis behind some NSAIDS-associated clinical entities is still unclear. Diagnosis is mostly based on a thorough clinical history and confirmed by a drug challenge test. Clinical management is based on strict avoidance and use of alternative tolerated medications. Overall, all therapeutic decisions depend on the correct identification of the type of reaction the patient experienced.

Montelukast as a potential treatment for COVID-19

INTRODUCTION

Montelukast is a leukotriene inhibitor that is widely used to treat chronic asthma and allergic rhinitis. The drug interferes with molecular signaling pathways produced by leukotrienes in a variety of cells and tissues throughout the human body that lead to tightening of airway muscles, production of aberrant pulmonary fluid (airway edema), and in some cases, pulmonary inflammation.

AREAS COVERED

Montelukast has also been noted to have anti-inflammatory properties, suggesting it may have a role in the treatment of coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has been noted to induce misfiring of the immune system in some patients. A literature search of PubMed was performed to identify all relevant studies of montelukast and SARS-CoV-2 through 27 January 2023.

EXPERT OPINION

Montelukast has been the subject of small studies of SARS-CoV-2 and will be included in a large, randomized, double-blind, placebo-controlled study of outpatients with COVID-19 sponsored by the United States National Institutes of Health known as Accelerating COVID-19 Therapeutic Interventions and Vaccines-6. This paper reviews what is known about montelukast, an inexpensive, well-tolerated, and widely available medication, and examines the rationale for using this drug to potentially treat patients with COVID-19.

Structural Basis for Developing Multitarget Compounds Acting on Cysteinyl Leukotriene Receptor 1 and G-Protein-Coupled Bile Acid Receptor 1

G-protein-coupled receptors (GPCRs) are the molecular target of 40% of marketed drugs and the most investigated structures to develop novel therapeutics. Different members of the GPCRs superfamily can modulate the same cellular process acting on diverse pathways, thus representing an attractive opportunity to achieve multitarget drugs with synergic pharmacological effects. Here, we present a series of compounds with dual activity toward cysteinyl leukotriene receptor 1 (CysLT₁R) and G-protein-coupled bile acid receptor 1 (GPBAR1). They are derivatives of REV5901─the first reported dual compound─with therapeutic potential in the treatment of colitis and other inflammatory processes. We report the binding mode of the most active compounds in the two GPCRs, revealing unprecedented structural basis for future drug design studies, including the presence of a polar group opportunely spaced from an aromatic ring in the ligand to interact with Arg79^2.60 of CysLT₁R and achieve dual activity.

Montelukast use over the past 20 years: monitoring of its effects and safety issues

Montelukast, a leukotriene receptor antagonist, was launched 20 years ago in Korea. It is recommended as an alternative treatment for asthma in children with mild persistent symptoms or as an add-on treatment to existing low-dose inhaled corticosteroids (ICSs) in children who require additional treatment. However, in the real-world setting, many doctors and patients prefer montelukast over ICSs despite their lower efficacy. Although montelukast is considered to be a safe drug, there are concerns regarding adverse drug reactions, including the rare occurrence of Churg-Strauss syndrome and, despite insufficient data, the possibility of neuropsychiatric events such as anxiety, depression, sleep disturbance, and suicidality. This review identified that montelukast has significantly contributed to asthma control over the past 20 years in Korea and has been critical for reducing asthma severity, especially early wheezing and disease control. Our findings suggest that the effects of montelukast treatment can be monitored by measuring serum eosinophilderived neurotoxin levels.

Eicosanoid mediator profiles in different phenotypes of nonsteroidal anti-inflammatory drug-induced urticaria

BACKGROUND

The role of arachidonic acid metabolites in NSAID-induced hypersensitivity has been studied in depth for NSAID-exacerbated respiratory disease (NERD) and NSAID-exacerbated cutaneous disease (NECD). However, no information is available for NSAID-induced urticarial/angioedema (NIUA), despite it being the most frequent clinical entity induced by NSAID hypersensitivity. We evaluated changes in leukotriene and prostaglandin metabolites for NIUA patients, using patients with NECD and single-NSAID-induced urticaria/angioedema or anaphylaxis (SNIUAA) for comparison.

METHODS

Urine samples were taken from patients with confirmed NSAID-induced urticaria and healthy controls, at baseline and at various time intervals after ASA administration. Eicosanoid measurement was performed using high-performance liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry.

RESULTS

No differences were found between groups at baseline. Following ASA administration, LTE4 and 9α,11β-PGF2 levels were increased in both NIUA and NECD patients compared to baseline, rising initially, before decreasing toward initial levels. In addition, the levels of these metabolites were higher in NIUA and NECD when compared with the SNIUAA and control groups after ASA administration. No changes were found with respect to baseline values for SNIUAA and control groups.

CONCLUSIONS

We present for the first time data regarding the role of COX-1 inhibition in NIUA. Patients with this entity show a similar pattern eicosanoid levels following ASA challenge to those with NECD. Further studies will help ascertain the cell populations involved and the underlying molecular mechanisms.

Individualized treatment for allergic rhinitis based on key nasal clinical manifestations combined with histamine and leukotriene D4 levels

Introduction

The types of allergic rhinitis are roughly classified based on the causative antigens, disease types, predilection time, and symptom severity.

Objective

To examine the clinical typing and individualized treatment approach for allergic rhinitis and to determine the optimal treatment method for this disease using various drug combination therapies.

Methods

A total of 108 participants with allergic rhinitis were divided into three groups based on symptoms. Subsequently, each group was further categorized into four subgroups based on the medications received. The efficacy of the treatments was evaluated using the visual analog scale VAS scores of the total and individual nasal symptoms, decline index of the symptom score, histamine and leukotriene levels, and mRNA and protein expression levels of histamine 1 and cysteinyl leukotriene 1 receptors.

Results

Loratadine + mometasone furoate and loratadine + mometasone furoate + montelukast significantly improved the sneezing symptom and reduced the histamine levels compared with the other combination therapies (p < 0.05). Meanwhile, montelukast + mometasone furoate and montelukast + mometasone furoate + loratadine considerably improved the nasal obstruction symptom and decreased the leukotriene D4 levels compared with the other combination therapies (p < 0.05).

Conclusion

Clinical symptom evaluation combined with experimental detection of histamine and leukotriene levels can be an objective and accurate method to clinically classify the allergic rhinitis types. Furthermore, individualized treatment based on allergic rhinitis classification can result in a good treatment efficacy.

The roles of toll like receptor 3, 7 and 8 in allergic rhinitis pathogenesis

Allergic rhinitis, as an allergic and nasal hypersensitivity disease, is associated with the inflammation of nasal mucosa. It appears that innate immune receptors are the important risk factors in the pathogenesis of the inflammatory disease. Toll-like receptors (TLRs) are the most important receptors of innate immunity; their crucial roles in the recognition of allergens and subsequently pathogenesis of allergic diseases have been evaluated recently. TLR3, 7 and 8 are the intracellular members of the innate immune receptors and recognize intracellular single and double strand RNAs. This review article collected the investigations regarding the roles of TLR3, 7 and 8 in the allergic rhinitis pathogenesis.

Evaluation of Montelukast for the Treatment of Children With Japanese Cedar Pollinosis Using an Artificial Exposure Chamber (OHIO Chamber)

Background

This study evaluated the efficacy of montelukast in reducing seasonal allergic rhinitis symptoms in Japanese children with Japanese cedar (JC) pollinosis induced in an artificial exposure chamber (OHIO Chamber).

Methods

Pediatric patients aged 10 to 15 years sensitive to JC pollen entered a randomized, double-blind, single-site, crossover study. After confirmation of an allergic response to a JC pollen exposure for 3 hours in the OHIO Chamber during the screening period, subjects received either montelukast 5 mg chewable tablets or placebo for a 7-day treatment period, followed by a 3-hour pollen exposure in the chamber. After a 7-day washout period, subjects crossed over to the other treatment. Subjects were instructed to self-assess their nasal symptoms using 5-point scale for every 30 minutes. The primary end point was the change from baseline (just before entering the exposure chamber for each exposure) in total nasal symptom score (TNSS; the sum of nasal congestion, nasal discharge, and sneezing scores) over 3 hours of pollen exposure. Adverse events (AEs) were evaluated throughout the study.

Results

A total of 220 subjects (median age, 12 years) received treatment. For TNSS, the between-group difference in the change (95% confidence interval) was −0.01 (−0.11 to 0.10); the change between placebo and montelukast 5 mg was not significant. TNSS in the screening and treatment periods after receiving placebo for 7 days was 1.58 and 1.31, respectively, suggesting a placebo response. On account of high placebo response, a post hoc analysis was conducted. The analysis in a subgroup of subjects who did not show placebo response demonstrated a difference in the efficacy between montelukast and placebo (nominal P < .037). The most common AE was positive urine protein (4.6% with montelukast vs 7.8% with placebo).

Conclusions

Although montelukast was well tolerated, this study did not demonstrate a treatment difference between active drug and placebo in Japanese children exposed to JC pollen in the OHIO Chamber.

Trial Registry: ClinicalTrials.gov, NCT01852812

The study of a possible correlation between serum levels of interleukin 17 and clinical severity in patients with allergic rhinitis

Introduction:

Allergic rhinitis (AR) is one of the most common allergic diseases, which affects ∼20% of the world's population. T-helper (Th) type 2 cells produce interleukin (IL) 4 and IL-13, and mediate allergic responses, and these cytokines have been extensively studied as key players in the atopic airway diseases. However, the involvement of Th17 cells and IL-17 in AR has not been clearly examined.

Aim:

To reevaluate AR clinical severity with serum IL-17, whether IL-17 affects the disease alone or in contribution with the atopic predisposition.

Patients and Methods:

During an 18-month period, 39 individuals were divided into three groups: A, (13 control), B (13 with mild-to-moderate AR), and C (13 with severe AR). Both group B and group C patients (26) were subjected to clinical examination and allergy skin testing, and to measurement of both total serum immunoglobulin E (IgE) and IL-17 levels. Eleven patients with AR then were exposed to 6 months of cluster immunotherapy, whereas the rest of the patients were not exposed.

Results:

Revealed a significant elevation of serum IL-17 levels with an associated increase in serum IgE in the patients with AR compared with controls and revealed that the serum levels of both total serum IgE and IL-17 decreased significantly after cluster immunotherapy.

Conclusion:

These preliminary results added new data about the use of injective immunotherapy as well as reported on the use of sublingual immunotherapy.

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.

The role of leukotrienes in allergic diseases

Leukotrienes (LTs), both LTB4 and the cysteinyl LTs (CysLTs) LTC4, LTD4 and LTE4, are implicated in a wide variety of inflammatory disorders. These lipid mediators are generated from arachidonic acid via multistep enzymatic reactions through which arachidonic acid is liberated from membrane phospholipids through the action of phospholipase A2. LTB4 and CysLTs exert their biological effects by binding to cognate receptors, which belong to the G protein-coupled receptor superfamily. LTB4 is widely considered to be a potent chemoattractant for most subsets of leukocytes, whereas CysLTs are potent bronchoconstrictors that have effects on airway remodeling. LTs play a central role in the pathogenesis of asthma and many other inflammatory diseases. This review will provide an update on the synthesis, biological function, and relevance of LTs to the pathobiology of allergic diseases, and examine the current and future therapeutic prospects of LT modifiers.

Role of leukotriene antagonists and antihistamines in the treatment of allergic rhinitis

Allergic rhinitis is the most common atopic disorder seen in ENT clinics. It is diagnosed by history, physical exam and objective testing. Patient education, environmental control measures, pharmacotherapy, and allergen-specific immunotherapy are the cornerstones of allergic rhinitis treatment and can significantly reduce the burden of disease. Current treatment guidelines include antihistamines, intranasal corticosteroids, oral and intranasal decongestants, intranasal anticholinergics, intranasal cromolyn, and leukotriene receptor antagonists. In the mechanism of allergic rhinitis, histamine is responsible for major allergic rhinitis symptoms such as rhinorrhea, nasal itching and sneezing. Its effect on nasal congestion is less evident. In contrast, leukotrienes result in increase in nasal airway resistance and vascular permeability. Antihistamines and leukotriene receptor antagonists are commonly used in the treatment of allergic rhinitis. The published literature about combined antihistamines and leukotriene antagonists in mono- or combination therapy is reviewed and presented.

What are the primary clinical symptoms of rhinitis and what causes them?

The nose has a limited repertoire of responses regardless of the triggers. These responses primarily serve as a protective mechanism for the lower respiratory tract. Although the nasal reactions to pollens, particles, and pollution may have a beneficial effect for the lower airway, they create symptoms in some individuals that lead to significant morbidity. The symptoms of allergic rhinitis extend far beyond the nose, and the morbidity associated with rhinitis is significant. The nasal symptoms of rhinitis and their causes are the focus of this review.

Is there a role for leukotriene antagonists in the prevention of recurrent nasal polyps?

PURPOSE OF REVIEW

The aim of this review is to provide the current available data for leukotriene receptor antagonists in the treatment of nasal polyps, the use in the postoperative therapy single or as an add-on to standard treatments.

RECENT FINDINGS

Surgical treatment of nasal polyps was refined in the last 30 years by the introduction of functional endoscopic sinus surgery and nasal endoscopy for monitoring nasal polyp patients. As the relapse is the main challenge and as nasal steroids only delay it, a more efficient treatment is needed. Leukotriene antagonists have effects on asthma and allergic rhinitis; preliminary data show some benefits in nasal polyps.

SUMMARY

In the surgery of nasal polyps, recurrence is the main problem. Steroids are the current standard therapy, but the limitations are obvious. The role of leukotrienes in the disorder of nasal polyps is well established now, and with the antagonists available, interest rose in treating nasal polyps. A total of 356 patients took part in several studies involving leukotriene antagonists in the nasal polyp population. Some studies have minor levels of evidence; the data show positive effects for patients in preoperative and postoperative studies and medical treatments. There were benefits as an add-on to steroids and data from allergic rhinitis studies also show possible synergism with antihistamines. There are hints for a positive effect on eosinophil inflammation, clinical symptom scores, nasal airflow, sneezing and postnasal drip. Although some effects are shown, more controlled studies are necessary for reliable data.

Rhinitis in the geriatric population

The current geriatric population in the United States accounts for approximately 12% of the total population and is projected to reach nearly 20% (71.5 million people) by 20301. With this expansion of the number of older adults, physicians will face the common complaint of rhinitis with increasing frequency. Nasal symptoms pose a significant burden on the health of older people and require attention to improve quality of life. Several mechanisms likely underlie the pathogenesis of rhinitis in these patients, including inflammatory conditions and the influence of aging on nasal physiology, with the potential for interaction between the two. Various treatments have been proposed to manage this condition; however, more work is needed to enhance our understanding of the pathophysiology of the various forms of geriatric rhinitis and to develop more effective therapies for this important patient population.

Levocetirizine for the treatment of allergic rhinitis and chronic idiopathic urticaria in adults and children

BACKGROUND

Levocetirizine (LCZ) is a second-generation antihistamine that was approved in January 2008 for the relief of symptoms of seasonal allergic rhinitis (SAR), perennial allergic rhinitis (PAR), and chronic idiopathic urticaria (CIU) in adults and children aged > or = 6 years.

OBJECTIVES

This article reviews the available literature on the pharmacokinetics and pharmacodynamics, clinical efficacy and tolerability, and effect on quality of life (QoL) of LCZ.

METHODS

A search of the English-language literature was performed using the following databases: MEDLINE (1966-February 2009), International Pharmaceutical Abstracts (19 70-February 2009), Database of Abstracts of Reviews of Effectiveness, Cochrane Database of Systematic Reviews, EMBASE Drugs & Pharmacology (1991-February 2009), Blackwell Synergy, CINAHL Plus with Full Text, EBSCOhost, ScienceDirect, and Wiley Interscience. The search terms were levocetirizine, allergic rhinitis, chronic idiopathic urticaria, antihistamine, pharmacokinetics, quality of life, drug interactions, case reports, and cost. Publications describing studies of > or = 2 weeks' duration that concerned the efficacy, tolerability, pharmacoeconomics, and/or QoL effects of LCZ were included in the review.

RESULTS

In 4 studies in adult patients with moderate to severe PAR, LCZ 5 mg/d was associated with significant improvements in symptom scores for sneezing, rhinorrhea, and ocular/nasal pruritus at 4 to 6 weeks compared with placebo (P < or = 0.05). In 3 studies, nasal congestion scores were significantly improved within 4 to 6 weeks compared with placebo (P < 0.001). LCZ 5 mg/d was associated with improvements compared with placebo in scores for the ability to do housework, complete work activities, and engage in outdoor activities at 6 months (P < or = 0.011). In a 6-week study in children with moderate to severe SAR, LCZ 5 mg/d was associated with significant improvements compared with placebo in sneezing, rhin-orrhea, and itchy nose (P < 0.004); significant improvements in symptoms from baseline were also seen in a 4-week study in adults with SAR (P < 0.001). One study in patients with SAR reported no significant difference between LCZ and fluticasone compared with fluticasone monotherapy in terms of improvement in QoL, nasal airflow obstruction, sneezing, or pruritus. In a 6-week study in patients with moderate to severe CIU, LCZ 5 mg/d was significantly more effective than placebo in reducing overall CIU symptoms (P < 0.05). In two 4-week studies, one comparing LCZ 5 mg/d with placebo and the other comparing it with desloratadine (DSL), LCZ was significantly more effective than either comparator in terms of improvement in scores for pruritus severity (P < or = 0.001 vs placebo; P < 0.004 vs DSL) and duration (P < or = 0.001 vs placebo; P = 0.009 vs DSL). LCZ was significantly more effective than placebo (but not DSL) in reducing the number and size of wheals (both, P = 0.001). In a 12-week, open-label, crossover study, patients reported significantly longer symptom relief with cetirizine than LCZ (P < 0.005). The most commonly reported adverse events in two 6-month studies in adults with PAR treated with LCZ 5 mg/d included headache (23.8%), pharyngitis (19.4%), influenza (14.6%), fatigue (8.3%), and somnolence (8.3%). There is serious concern about the possibility of febrile seizures in infants treated with LCZ. Three pharmacoeconomic studies of LCZ 5 mg/d were identified, one comparing it with placebo in patients with PAR, one comparing it with placebo in patients with CIU, and another comparing it with second-generation antihistamines and montelukast in patients with PAR. Because of design limitations and differences in comparators in these studies, it was not possible to determine the cost-effectiveness of LCZ in the treatment of PAR or CIU.

CONCLUSIONS

In the studies reviewed, LCZ 5 mg/d was effective in reducing symptoms of PAR, SAR, and CIU and improving QoL, with an acceptable tolerabili-ty profile. There is a need for studies of longer durations, head-to-head comparisons against other anti-histamines, drug-interaction studies, safety studies in infants, and cost-effectiveness analyses.

Leukotriene receptor antagonist in the treatment of childhood allergic rhinitis--a randomized placebo-controlled study

OBJECTIVE

This study was designed to assess the hypothesis that leukotriene receptor antagonists (LTRAs) would provide additional symptom relief in asthmatic children with persistent AR already taking regular antihistamine. The effects of 16-week treatment of LTRA in addition to fexofenadine (FEX) on persistent AR in asthmatic children were examined.

STUDY DESIGN

Consecutive children with stable asthma and persistent AR were invited in this randomized, double-blind, placebo-controlled study. After a 2-week run-in period in which subjects were given FEX alone, they were randomly assigned to take LTRA or placebo in addition to FEX for 16 weeks, followed by 8 weeks of follow-up phase with FEX taken alone. Symptom scoring, rhinoscopy, acoustic rhinometry, spirometry, nasal secretion extraction and blood taking for IL-4 and IL-13 analysis were performed after a 2-week run-in and at the end of treatment.

RESULTS

Forty-four subjects with a median (IQR) age of 12.2 (10.1-14.1) years were recruited. At week 4 of treatment, the between-group differences in the mean changes of daytime sneezing score (mean difference (95% CI) = -0.35 (-0.59, -0.12), P = 0.004), nighttime sneezing score (mean difference (95% CI) = -0.37 (-0.62, -0.11), P = 0.007) and daytime composite score (mean difference (95% CI) = -1.08 (-1.92, -0.25), P = 0.013) were significant. Acoustic rhinometry also demonstrated a nearly significant difference in nasal volume change between groups at 16 weeks of treatment (mean difference (95% CI) = 0.572 (0.090-1.054), P = 0.021). IL-4 and IL-13 were not detected in the majority of nasal secretion or serum samples.

CONCLUSIONS

Additional LTRA provided a more rapid relief on sneezing at the 4-week time point. This combination therapy also maintained a greater nasal volume and this might translate to lesser nasal congestion.

High-level expression of early growth response-1 and association of polymorphism with total IgE and atopy in allergic rhinitis adults

BACKGROUND

Early growth response-1 (Egr-1) is expressed in human airways and its polymorphisms have been associated with total IgE and atopy in asthmatic patients. We investigated the effects of Chinese-tagging single nucleotide polymorphism (SNP) of Egr-1 and its mRNA expression on allergic rhinitis (AR) traits.

METHODS

Among 214 Chinese AR adults and 259 controls, tag SNP -4071 A-->G was genotyped and mRNA expression in peripheral blood was quantified by real-time PCR.

RESULTS

Egr-1 mRNA expression was significantly higher in patients than controls (median of 0.23 vs 0.15 fold GAPDH expression; p<0.001). Its expression was not associated with -4071 polymorphism. However, significant correlations were found between -4071 A-->G with increased plasma total IgE (p=0.028) and atopy (p=0.030) in patients. Logistic regression confirmed the association (p=0.034) with age and gender adjusted. Patients homozygous for the A allele had a 2.3-fold and 1.9-fold risks, respectively of having increased plasma total IgE and atopy than those G allele carriers.

CONCLUSIONS

We showed high levels of Egr-1 mRNA expression and demonstrated a significant association of polymorphism with increased plasma total IgE and atopy in AR patients. It may be useful to explore the pharmacogenetics of Egr-1 inhibitors.

Loratadine and montelukast administered in combination produce decongestion in an experimental feline model of nasal congestion

BACKGROUND

Histamine and leukotrienes act to exert numerous local and systemic effects that contribute to the pathophysiology of allergic rhinitis. The aim of these experiments was to evaluate the nasal decongestant effects of loratadine and montelukast alone and in combination in a feline model of nasal congestion. We also studied the decongestant actions of the alpha-agonist adrenergic agonist D-pseudoephedrine with and without desloratadine.

METHODS

Acoustic rhinometry was used to determine nasal cavity dimensions after intranasal compound 48/80. Cats were given D-pseudoephedrine (0.3 mg/kg) alone or in combination with desloratadine (5 mg/kg) 1 hour before nasal provocation with compound 48/80 (1%, 75 microliters) to either the left or right nasal passageway. Using a similar design, the nasal decongestant effects of montelukast (1 mg/kg) and loratadine (10 mg/kg) were studied alone and in combination.

RESULTS

The addition of desloratadine to D-pseudoephedrine did not improve decongestant efficacy compared with each drug given individually. In contrast, when montelukast (1 mg/kg) was given in combination with loratadine (10 mg/kg), the decongestant activity was greater than when these drugs were administered separately. Sixty minutes after compound 48/80 provocation the nasal cavity volume ratio (volume ratio of the compound 48/80 treated/untreated nasal passageway) for the control, montelukast alone, loratadine alone, and the montelukast plus loratadine-treated groups were 0.20 +/- 0.03, 0.24 +/- 0.01, 0.28 +/- 0.03, and 0.50 +/- 0.03.

CONCLUSION

Concomitant montelukast plus loratadine produces a greater degree of nasal decongestion compared with montelukast or loratadine alone in an experimental model of nasal congestion.

Optimal management of nasal congestion caused by allergic rhinitis in children: safety and efficacy of medical treatments

Nasal congestion is such a frequent and multifactorial occurrence in young children that parents and medical caregivers often overlook the need for medical intervention. However, children with congestion can suffer quality-of-life detriments resulting from sleep disturbance, learning impairment, and fatigue. Congestion also impairs the normal nasal breathing that is physiologically important for the efficient cleaning and conditioning of inspired air. Further, the most common cause of congestion, allergic rhinitis, is considered a potential risk factor for asthma. Published guidelines on the treatment of allergic rhinitis agree that management strategies in children should follow the same principles as in adults, while recognizing the need for dosage adjustments and being aware of unique safety issues. Intranasal corticosteroids, with robust effects in reducing congestion and good tolerability, remain a treatment of choice. Despite lingering concerns about the potential for growth suppression with these drugs, clinical evidence suggests a very low risk at prescribed dosages, especially with compounds that have a low systemic bioavailability. Oral antihistamines are commonly cited as first-line options for allergic rhinitis, although their effect on nasal congestion is relatively modest. First-generation antihistamines should not be administered to children because of their sedative properties, which can worsen learning problems associated with allergic rhinitis. Second-generation oral antihistamines are preferred, although this class is not completely devoid of adverse effects. Other treatments, such as a nasal antihistamine, decongestants, and immunotherapy, present varying levels of safety and tolerability issues in children.

Clinical effects of far-infrared therapy in patients with allergic rhinitis

Allergic rhinitis (AR) is the sixth most common chronic illness worldwide, which has a significant impact on patients' quality of life. The actual cost of AR is staggering, approximately $5.6 billion being spent annually in direct medical costs and other indirect costs. Therefore, it should be taken seriously upon its evaluation and treatment. AR is an IgE-mediated inflammation, which symptoms are likely due to increased vascular permeability. Current therapeutic options such as avoidance of allergen, medication and immunotherapy are unsatisfactory. Far-infrared (FIR) is an invisible electromagnetic wave with a wavelength longer than that of visible light. It has been used to treat vascular diseases as a result of an increase in blood flow. The objective of this study was to evaluate the clinical effects of FIR therapy in patients with AR. Thirty-one patients with AR were enrolled in this study. A WS TY101 FIR emitter was placed to face the patient's nasal region at a distance of 30 cm. The treatment was performed for 40 min every morning for 7 days. Every day, patients recorded their symptoms in a diary before and during treatment. Each symptom of rhinitis was rated on a 4-point scale (0-3) according to severity. During the period of FIR therapy, the symptoms of eye itching, nasal itching, nasal stuffiness, rhinorrhea and sneezing were all significantly improved. Smell impairment was not improved until after the last treatment. No obvious adverse effect was observed in the patients during treatment and follow-up. We concluded that FIR therapy could improve the symptoms of AR and might serve as a novel treatment modality for AR.

Cysteinyl-leukotrienes and their receptors in asthma and other inflammatory diseases: critical update and emerging trends

Cysteinyl-leukotrienes (cysteinyl-LTs), that is, LTC4, LTD4, and LTE4, trigger contractile and inflammatory responses through the specific interaction with G protein-coupled receptors (GPCRs) belonging to the purine receptor cluster of the rhodopsin family, and identified as CysLT receptors (CysLTRs). Cysteinyl-LTs have a clear role in pathophysiological conditions such as asthma and allergic rhinitis (AR), and have been implicated in other inflammatory conditions including cardiovascular diseases, cancer, atopic dermatitis, and urticaria. Molecular cloning of human CysLT1R and CysLT2R subtypes has confirmed most of the previous pharmacological characterization and identified distinct expression patterns only partially overlapping. Interestingly, recent data provide evidence for the immunomodulation of CysLTR expression, the existence of additional receptor subtypes, and of an intracellular pool of CysLTRs that may have roles different from those of plasma membrane receptors. Furthermore, genetic variants have been identified for the CysLTRs that may interact to confer risk for atopy. Finally, a crosstalk between the cysteinyl-LT and the purine systems is being delineated. This review will summarize and attempt to integrate recent data derived from studies on the molecular pharmacology and pharmacogenetics of CysLTRs, and will consider the therapeutic opportunities arising from the new roles suggested for cysteinyl-LTs and their receptors.

Syk inhibitors as treatment for allergic rhinitis

Allergic rhinitis is characterized by a hypersensitive immune response in the upper airways to seasonal or perennial allergens leading to episodes of sneezing, itching, runny nose and nasal congestion. These symptoms are mainly the manifestations of a large number of mediators released by mast cells and basophils localized in the nasal mucosa, following their activation via allergen-specific immunoglobulin E (IgE) receptors. Current medications antagonize the action of distinct mediators such as histamine and leukotrienes for symptom relief, or block the production of pro-inflammatory cytokines to suppress allergic inflammation. Notably, rather than neutralizing individual mediators, Syk kinase inhibitors can block the allergen-induced release of all mast cell mediators and the production of most eicosanoids and cytokines. Thus, Syk kinase represents an attractive therapeutic target for acute and chronic allergic inflammation. Syk kinase inhibitors are now entering clinical trials. Using cell-based structure-activity relationships with primary human mast cells, a series of 2,4-diaminopyrimidine Syk kinase inhibitors was developed. One of these compounds, referred to as R112, exhibited suitable characteristics for intranasal delivery and was tested for safety and efficacy in allergic rhinitis patients. In a park environment, R112 showed remarkable amelioration of acute allergic rhinitis symptoms with rapid onset of action. These results demonstrate the clinical significance of inhibiting Syk in allergic upper airway disorders.

Participation in cysteinyl leukotrienes and thromboxane A2 in nasal congestion model in Brown Norway rats

The aim of this study was to investigate the involvement of chemical mediators in a nasal congestion model in Brown Norway (BN) rats. For the above purpose, we studied the effects of pranlukast and zafirlukast (cysteinyl leukotriene (cys-LT) receptor antagonists), seratrodast and ramatroban (thromboxane A(2) (TXA(2)) receptor antagonists) on nasal congestion and sneezing induced by toluene 2, 4-diisocyanate (TDI). All of these drugs suppressed the increase of enhanced pause (Penh), the index of nasal congestion, in both early and late phase responses; however, pranlukast, zafirlukast and seratrodast failed to suppress immediate sneezing caused by TDI challenge. These results indicate that cys-LTs and TXA(2) are responsible for the development of both early and late phase nasal congestion. Moreover, these chemical mediators contribute very little to immediate sneezing in a BN rat model of allergic rhinitis.

Expression of cyclooxygenase-2 and 5-lipoxygenase in nasal polyps associated with interleukin-4 promoter polymorphism -590

OBJECTIVE

To evaluate expression of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO) associated with interleukin (IL)-4 promoter polymorphism -590 in nasal polyp tissues.

STUDY DESIGN AND SETTING

A prospective controlled study. A venous blood sample was taken to determine the genotype in 61 nasal polyp subjects. The C-590T variant was determined by the polymerase chain reaction-restriction fragment length polymorphism method. The expression of 5-LO and COX-2 was determined with immunohistochemical staining in 37 nasal polyp tissues associated with genotype.

RESULTS

The genotype frequencies at position -590 of the IL-4 gene in the patients with nasal polyp were C/C (8.20%), C/T (40.98%), and T/T (50.82%). There was no significantly increased expression of COX-2 among genotypes. The 5-LO expression was significantly increased in C/C compared with C/T and T/T.

CONCLUSION

We suggested that the IL-4 promoter polymorphism -590 C/C is associated with the expression of 5-LO in the patients with nasal polyp.

Pathophysiology of nasal obstruction and meta-analysis of early and late effects of levocetirizine

Nasal obstruction, also referred to as congestion, blockage or stuffiness, is a crucial symptom in allergic rhinitis (AR) and may affect sleep as well as quality of life. Early- and late-phase-allergic reactions both contribute to nasal obstruction, although it primarily represents a major symptom in the chronic allergic reaction. A complex network of inflammatory and neurogenic phenomena relates to chronic nasal obstruction, including the subepithelial accumulation of inflammatory cells, particularly mast cells and eosinophils, and the release of neuropeptides. Nasal obstruction is a difficult-to-treat symptom. Vasoconstrictors (decongestants) and intranasal corticosteroids, due to their anti-inflammatory properties, have mainly been used for relieving the nasal passages from the congested mucosa. However, there is accumulating evidence recently that the latest-generation potent antihistamines have decongestant properties in AR. This paper aims to review the pathophysiologic background of nasal obstruction and the evidence for an antihistamine, levocetirizine, in relieving nasal congestion. A meta-analysis on the early and late effects of levocetirizine on nasal obstruction under artificial and natural allergen exposure conditions is presented, demonstrating convincingly that levocetirizine shows a consistent effect on nasal obstruction as early as over the first 2 h and sustained over 6 weeks.

An update of the leukotriene modulators for the treatment of asthma

Bronchial asthma is a chronic inflammatory airway disease involving many cells and mediators. Chronic inflammation constitutes an important predisposing condition for airway remodelling with secondary irreversible airflow obstruction. Current approaches for asthma treatment involve many classes of drugs, adequate patient education for their correct use, environmental exposure control and daily monitoring of pulmonary function. Unfortunately, the use of multiple therapies complicates treatment regimens, thus leading to a reduced compliance to therapy. Available evidence from randomised clinical trials and real-word experience derived from managing patients with asthma justifies a broader role for leukotriene receptor antagonist drugs in asthma management than that recommended in the National Asthma Education and Prevention Programme and National Health Lung and Blood Institute Treatment Guidelines. While a low dose of inhaled corticosteroids remains the reference drug as a controller in mild-to-moderate persistent asthma, oral therapy with an leukotriene-receptor antagonist drug represents a good option providing the clinical efficacy requested in common clinical practice. For this reason the recent Global Initiative for Asthma Guidelines allocate this drug to the second and third steps of asthma treatment.

Psychologische Aspekte der Allergischen Rhinitis

Zusammenfassung. Theoretischer Hintergrund und Fragestellung: Die allergische Rhinitis ist die häufigste atopische Erkrankung, ihre Prävalenz scheint stetig zuzunehmen. Wie bei anderen chronischen Erkrankungen ist ein Einfluss psychischer Faktoren auf das Krankheitsgeschehen wahrscheinlich. Methode: Die vorliegende Übersichtsarbeit stellt Befunde aus 70 Jahren Forschung zur Psychologie der allergischen Rhinitis zusammen. Diese werden in ein Gliederungsraster integriert, das die Einordnung biopsychosozialer Bedingungsfaktoren erlaubt und die Manifestation auf verschiedenen Verhaltens- und Erlebensebenen berücksichtigt. Ergebnisse und Schlussfolgerungen: Krankheitsverhalten, Laienstörungskonzepte, Neurotizismus und psychophysiologische Stressreaktivität stellen psychologische Aspekte dar, die zur Chronizität der Erkrankung und zur subjektiven Beeinträchtigung beitragen. Es besteht in diesem Bereich noch erheblicher Forschungsbedarf.

Current concepts and therapeutic strategies for allergic rhinitis in school-age children

BACKGROUND

Allergic rhinitis (AR) is a common debilitating disorder that can adversely affect the quality of life and the academic performance of school-age children. Symptoms during the day can hamper concentration and lead to learning problems. Nocturnal symptoms can cause sleep loss and secondary daytime fatigue, further undermining a child's ability to function well during the school day Oral antihistamines are the foundation of pharmacologic therapy, but there are important differences between the agents.

OBJECTIVE

The purpose of this review is to provide an overview of the diagnostic and treatment challenges posed by AR in school-age children. The paper discusses and compares the available treatment modalities for this age group, with a focus on their beneficial and adverse effects.

METHODS

Pertinent articles were identified in the literature through a MEDLINE search (1990-2003). Keywords used were antihistamines cetirizine fexofenadine loratadine desloratadine intranasal corticosteroids and CNS effects. Results of numerous clinical trials of first-generation early second-generation and the newer antihistamines were identified.

RESULTS

This review established that the socioeconomic costs of AR are considerable. In children aged > or =12 years, direct US expenditures (eg, physician visits, medications) in 1996 amounted to $2.3 billion. Indirect costs measured by variables such as missed school days and poor performance also have an impact Major concerns include underdiagnosis and inadequate treatment, increasing the risk of serious comorbid conditions such as asthma. Advantages and drawbacks of antihistamines show that first-generation agents (eg, hydroxyzine) are effective and readily available over the counter, but are associated with sedation and the potential for suboptimal dosing. Newer agents, such as cetirizine, loratadine, desloratadine, and fexofenadine are effective and safer than the older drugs tie, no cardiotoxicity and less sedation). Of these, fexofenadine has been shown to be beneficial and nonsedating, even at higher-than-recommended doses. Other therapies reviewed include intranasal corticosteroids and leukotriene modifiers.

CONCLUSIONS

AR has a considerable negative impact on children in terms of their physical, social, and psychological well-being and academic performance. An appropriate treatment must be effective and tolerable. Of particular importance for enhancing treatment adherence in the school-age population are pleasant taste and ease of use of medication. A drug that has minimal or no sedative or anticholinergic effects is optimal.

Therapeutic modulation of allergic airways disease with leukotriene receptor antagonists

Although asthma is one of the most common chronic respiratory conditions, it often remains unrecognized and undertreated, while patients are often reluctant to comply with regular inhaled anti-inflammatory and bronchodilator therapy. Allergic rhinitis co-exists with asthma in as many as 40% of patients, and can be regarded as a continuum of the same inflammatory disease process. Corticosteroids are the 'gold standard' first-line treatment for both conditions, and have a significant impact upon underlying inflammation, symptoms and long-term outcome. Cysteinyl leukotrienes are potent airway inflammatory mediators, suggesting that treatment antagonizing their effects could play a role in disease management. In recent years, leukotriene receptor antagonists have provided a further therapeutic option in the management of allergic airways disease. These drugs are orally active, can be administered once daily, and provide a systemic approach to the management of patients with asthma and allergic rhinitis. We review the pharmacology of leukotriene receptor antagonists, their potential role in clinical practice in patients with allergic airways disease, and likely areas for further research.

Pediatric chronic rhinosinusitis

PURPOSE OF REVIEW

Pediatric sinusitis is prevalent, and the debate continues regarding how best to care for these children. Although acute sinusitis is commonly associated with an upper respiratory infection, the focus of this paper is on chronic rhinosinusitis in children. Research is often more difficult in children than adults, so many times one can learn from the adult literature and determine whether there can be application to the childhood population.

RECENT FINDINGS

This paper looks at both medical and surgical treatment of chronic rhinosinusitis. "Maximal medical management" is often cited in the literature, but what this should consist of has never been clearly proved in the literature. Alternative medicine approaches as well as irrigation as an adjunct to care are discussed. Biomaterials are also be discussed. Recent outcome data are put in perspective.

SUMMARY

Hopefully the reader will find the presentation stimulating. The paper does not promote surgery as a "cure all," and in the end, analysis will hopefully leave the reader more cautious but with a better understanding of this complex disease.