Intranasal capsaicin is lacking therapeutic effect in perennial allergic rhinitis to house dust mite. A placebo-controlled study

Epithelial and sensory mechanisms of nasal hyperreactivity

"Nasal hyperreactivity" is a key feature in various phenotypes of upper airway diseases, whereby reactions of the nasal epithelium to diverse chemical and physical stimuli are exacerbated. In this review, we illustrate how nasal hyperreactivity can result from at least three types of mechanisms: (1) impaired barrier function, (2) hypersensitivity to external and endogenous stimuli, and (3) potentiation of efferent systems. We describe the known molecular basis of hyperreactivity related to the functional impairment of epithelial cells and somatosensory innervation, and indicate that the thermal, chemical, and mechanical sensors determining hyperreactivity in humans remain to be identified. We delineate research directions that may provide new insights into nasal hyperreactivity associated with rhinitis/rhinosinusitis pathophysiology and therapeutics. The elucidation of the molecular mechanisms underlying nasal hyperreactivity is essential for the treatment of rhinitis according to the precepts of precision medicine.

A TRiP Through the Roles of Transient Receptor Potential Cation Channels in Type 2 Upper Airway Inflammation

PURPOSE OF REVIEW

Despite their high prevalence, the pathophysiology of allergic rhinitis (AR) and chronic rhinosinusitis (CRS) remains unclear. Recently, transient receptor potential (TRP) cation channels emerged as important players in type 2 upper airway inflammatory disorders. In this review, we aim to discuss known and yet to be explored roles of TRP channels in the pathophysiology of AR and CRS with nasal polyps.

RECENT FINDINGS

TRP channels participate in a plethora of cellular functions and are expressed on T cells, mast cells, respiratory epithelial cells, and sensory neurons of the upper airways. In chronic upper airway inflammation, TRP vanilloid 1 is mostly studied in relation to nasal hyperreactivity. Several other TRP channels such as TRP vanilloid 4, TRP ankyrin 1, TRP melastatin channels, and TRP canonical channels also have important functions, rendering them potential targets for therapy. The role of TRP channels in type 2 inflammatory upper airway diseases is steadily being uncovered and increasingly recognized. Modulation of TRP channels may offer therapeutic perspectives.

Allergic Rhinitis Improvement in Asthmatic Children After Using Acaricidal Bait: A Randomized, Double-Blind, Cross-Placebo Study

Objective: This study aimed to evaluate the effects of acaricidal bait use on the house dust mite (HDM) allergen concentration and occurrence of allergic rhinitis (AR) and asthma symptoms in children sensitized to HDMs. Study Design: Sixty-six children (3-12 years old) with AR and asthma sensitized to HDMs were randomly assigned to receive an acaricidal bait intervention for 8 weeks and a placebo intervention for 8 weeks separated by a 4-week washout period. The visual analog scale (VAS) score, rhinitis control assessment test (RCAT) score, rhinoconjunctivitis quality of life questionnaire (RQLQ) score, asthma control questionnaire-5 (ACQ-5) score and HDM allergen levels were monitored. Results: HDM allergen levels were significantly decreased after 8 weeks (Δder p2+f2 2.282 (3.516) μg/g vs. 0.147 (0.25) μg/g, P < 0.05) in the acaricidal bait group compared with the placebo group. The VAS, RCAT and RQLQ scores in the acaricidal bait group were also significantly improved (ΔVAS 7.5 (16) vs. 3 (18), P < 0.05; ΔRCAT-3 (5) vs. 0 (7), P < 0.05; ΔRQLQ 4.5 (8) vs. 1 (8), P < 0.05), but the ACQ-5 score did not improve (ΔACQ-5 0.2 (0.4) vs. 0 (0.65), P > 0.05). Conclusion: Acaricidal bait reduced HDM exposure and improved rhinitis symptoms. This trial is registered at www.chictr.org.cn.

Research on allergic rhinitis improvement in asthmatic children after dust mite exposure reduction: a randomized, double-blind, cross-placebo study protocol

Background

Allergic rhinitis (AR) in children is a major respiratory inflammatory disease with a high incidence that is increasing yearly. In China, 54.93% of children with asthma have AR, which often requires synchronous treatment. House dust mites (HDMs) are common allergens that often cause attacks of AR and asthma. Reducing allergen exposure is one of the most important measures to control and treat AR and asthma attacks. Hestelia Mite Bait, containing 0.1% emamectin, is a new tool for trapping and killing dust mites, reducing the number of dust mites on mattresses and thereby potentially reducing stimulation by allergens and ultimately improving asthma and rhinitis symptoms. This single-centre, randomized, double-blind, cross-placebo trial will explore the improvement in AR in asthmatic children after dust mite exposure reduction.

Methods

We will recruit 60 children (aged 3–12 years) who have been diagnosed with AR and asthma and are allergic to dust mites as confirmed by a serum allergen test. Participants will randomly receive the Hestelia Mite Bait intervention for 8 weeks and the placebo intervention for 8 weeks. There will be a 4-week washout period between the two interventions. The primary outcome is the visual analogue scale (VAS) score of AR symptoms; the secondary outcomes include the Rhinitis Control Assessment Test (RCAT) score, Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score, changes in the dust mite level, drug usage for asthma and AR, Asthma Control Questionnaire-5 (ACQ-5) score, and frequencies of acute asthma attacks, emergency visits, and hospitalizations.

Discussion

This study aims to scientifically and objectively evaluate the effects of mite bait on rhinitis and asthma improvement after dust mite exposure reduction and provides a convenient means for future prevention and treatment of allergic diseases involving the airways in children.

Trial registration

www.chictr.org.cn ChiCTR1900024688. Registered on July 21, 2019

Rhinitis 2020: A practice parameter update

This comprehensive practice parameter for allergic rhinitis (AR) and nonallergic rhinitis (NAR) provides updated guidance on diagnosis, assessment, selection of monotherapy and combination pharmacologic options, and allergen immunotherapy for AR. Newer information about local AR is reviewed. Cough is emphasized as a common symptom in both AR and NAR. Food allergy testing is not recommended in the routine evaluation of rhinitis. Intranasal corticosteroids (INCS) remain the preferred monotherapy for persistent AR, but additional studies support the additive benefit of combination treatment with INCS and intranasal antihistamines in both AR and NAR. Either intranasal antihistamines or INCS may be offered as first-line monotherapy for NAR. Montelukast should only be used for AR if there has been an inadequate response or intolerance to alternative therapies. Depot parenteral corticosteroids are not recommended for treatment of AR due to potential risks. While intranasal decongestants generally should be limited to short-term use to prevent rebound congestion, in limited circumstances, patients receiving regimens that include an INCS may be offered, in addition, an intranasal decongestant for up to 4 weeks. Neither acupuncture nor herbal products have adequate studies to support their use for AR. Oral decongestants should be avoided during the first trimester of pregnancy. Recommendations for use of subcutaneous and sublingual tablet allergen immunotherapy in AR are provided. Algorithms based on a combination of evidence and expert opinion are provided to guide in the selection of pharmacologic options for intermittent and persistent AR and NAR.

Recent developments and highlights in rhinitis and allergen immunotherapy

This review paper aims to provide an overview of recent developments in the field of allergic and non-allergic rhinitis, as well as allergen immunotherapy. Recent advances in phenotyping and endotyping various forms of rhinitis have brought us one step closer towards tailoring treatment more appropriately for a given patient. Updates on local allergic rhinitis are also covered. Allergen immunotherapy (AIT) is an area of significant interest, with multiple original papers and recent position papers and guidelines published. Evidence related to the application of AIT in seasonal and perennial allergic rhinitis (AR), local allergic rhinitis and novel and expanded applications is discussed in the publication.

Nasal hyperreactivity in rhinitis: A diagnostic and therapeutic challenge

Although nasal hyperreactivity (NHR) is a common feature in patients suffering from allergic and nonallergic rhinitis, it is widely neglected during history taking, underdiagnosed in the majority of patients with rhinitis and rhinosinusitis, not considered as an outcome parameter in clinical trials on novel treatments for rhinitis and rhinosinusitis, and no target for routine treatment. In contrast to the simple nature of diagnosing NHR by a history of nasal symptoms induced by nonspecific exogenous and/or endogenous triggers, quantification is hardly performed in routine clinic given the lack of a simple tool for its diagnosis. So far, limited efforts have been invested into gaining better insight in the underlying pathophysiology of NHR, helping us to explain why some patients with inflammation develop NHR and others not. Of note, environmental and microbial factors have been reported to influence NHR, contributing to the complex nature of understanding the development of NHR. As a consequence of the neglect of NHR as a key clinical feature of rhinitis and chronic rhinosinusitis (CRS), patients with NHR might be suboptimally controlled and/or dissatisfied with current treatment. We here aim to provide a comprehensive overview of current knowledge on the pathophysiology, and the available tools to diagnose and treat NHR.

Females have stronger neurogenic response than males after non-specific nasal challenge in patients with seasonal allergic rhinitis

Epidemiological studies show female predominance in the prevalence of non- allergic rhinitis (NAR) and local allergic rhinitis (LAR). Experimental studies show female patients with allergic rhinitis (AR) demonstrate higher levels of sensitivity to irritants and airway hyperresponsiveness than males. Bronchial asthma shows female predominance in post-puberty patients, and gender interaction with severe asthma endotypes. Fibromyalgia, chronic fatigue syndrome, migraine and chronic cough, syndromes, which are commonly related to neurokinin substance P (SP) in the literature, also show strong female predominance. Studies have demonstrated that sex hormones, primarily oestrogens, affect mast cell activation. Mast cell proteases can amplify neurogenic inflammatory responses including the release of SP. Based on human epidemiological data and animal experimental data we hypothesized that female patients have different interaction between mast cell activation and neurogenic inflammation, i.e. substance P release, resulting in a different nasal symptom profile. To test the hypothesis we performed allergen and non-specific nasal challenges in patients with seasonal allergic rhinitis (SAR) out of season and looked for gender differences in subjective and objective responses. The interaction between subjective and objective reactivity was evaluated through the comparison of subjective symptom scores, concentrations of neurokinin substance P (SP) and cellular markers in nasal lavages after low doses of nasal allergen challenges. Female allergic subjects tended to have higher substance P (SP) concentrations both before and after non-specific challenges. The difference between post-allergen and post - hypertonic saline (HTS) challenge was highly significant in female patients (p = 0.001), while insignificant in male subjects (p = 0.14). Female patients had significantly stronger burning sensation after HTS challenge than male. These data indicate difference in the interaction between inflammatory cells and the neurogenic response, which is gender- related, and which may affect symptom profiles after challenges. Different regulation of neurogenic inflammation in females may have impact on symptoms and endotyping in respiratory disorders, not only in allergic rhinitis, but also asthma, chronic rhinosinusitis and irritant -induced cough.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Burden of allergic respiratory disease: a systematic review

This meta-analysis compared the health-related quality of life (HRQL) of patients with allergic rhinitis (AR) and/or allergic asthma (AA) caused by perennial house dust mite (HDM) versus AR and/or AA caused by seasonal pollen allergy. Following a systematic search, the identified studies used the disease-specific rhinitis quality of life questionnaire or generic instruments (SF-36 and SF-12). Summary estimates obtained by meta-analysis showed that HRQL in patients with perennial HDM allergy was significantly worse than that of patients with seasonal pollen allergy, when measured by both disease-specific and generic HRQL instruments, and was reflected by an impact on both physical and mental health. A systematic review of cost data on AR and AA in selected European countries demonstrated that the majority of the economic burden was indirectly caused by high levels of absenteeism and presenteeism; there was little or no evidence of increasing or decreasing cost trends. Increased awareness of the detrimental effects of AR and/or AA on patients’ HRQL and its considerable cost burden might encourage early diagnosis and treatment, in order to minimize the disease burden and ensure beneficial and cost-effective outcomes.

Capsaicin for Rhinitis

Rhinitis is a multifactorial disease characterized by symptoms of sneezing, rhinorrhea, postnasal drip, and nasal congestion. Non-allergic rhinitis is characterized by rhinitis symptoms without systemic sensitization of infectious etiology. Based on endotypes, we can categorize non-allergic rhinitis into an inflammatory endotype with usually eosinophilic inflammation encompassing at least NARES and LAR and part of the drug induced rhinitis (e.g., aspirin intolerance) and a neurogenic endotype encompassing idiopathic rhinitis, gustatory rhinitis, and rhinitis of the elderly. Patients with idiopathic rhinitis have a higher baseline TRPV1 expression in the nasal mucosa than healthy controls. Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is the active component of chili peppers, plants of the genus Capsicum. Capsaicin is unique among naturally occurring irritant compounds because the initial neuronal excitation evoked by it is followed by a long-lasting refractory period, during which the previously excited neurons are no longer responsive to a broad range of stimuli. Patients with idiopathic rhinitis benefit from intranasal treatment with capsaicin. Expression of TRPV1 is reduced in patients with idiopathic rhinitis after capsaicin treatment. Recently, in a Cochrane review, the effectiveness of capsaicin in the management of idiopathic rhinitis was evaluated and the authors concluded that given that many other options do not work well in non-allergic rhinitis, capsaicin is a reasonable option to try under physician supervision. Capsaicin has not been shown to be effective in allergic rhinitis nor in other forms of non-allergic rhinitis like the inflammatory endotypes or other neurogenic endotypes like rhinitis of the elderly or smoking induced rhinitis.

Capsaicin: Current Understanding of Its Mechanisms and Therapy of Pain and Other Pre-Clinical and Clinical Uses

In this review, we discuss the importance of capsaicin to the current understanding of neuronal modulation of pain and explore the mechanisms of capsaicin-induced pain. We will focus on the analgesic effects of capsaicin and its clinical applicability in treating pain. Furthermore, we will draw attention to the rationale for other clinical therapeutic uses and implications of capsaicin in diseases such as obesity, diabetes, cardiovascular conditions, cancer, airway diseases, itch, gastric, and urological disorders.

Allergic rhinitis: an update on disease, present treatments and future prospects

Allergic rhinitis (AR) is an inflammation of nasal mucosa mediated by IgE-associated processes occurring independently, or concurrently with asthma. AR is characterized by sensitization-formation and expression of antigen specific IgE, followed by inflammation in two phases. The early phase response involves cross linking of IgE molecules leading to degranulation of mast cells and release of preformed mediators such as histamine and tryptase, or newly synthesized mediators such as prostaglandins and leukotrienes. The late phase response is predominated by the presence of eosinophils, lymphocytes, cytokines, and adhesion molecules. Newer insights reveal that the whole phenomenon of immunological inflammation is intricately knit with neural pathways, which strongly influence the process. Furthermore, AR can impact psychological health and vice versa. Classical pharmacotherapy of AR includes use of oral or topical antihistamines, oral antileukotrienes, topical corticosteroids, mast cell stabilizers, decongestants, and an anticholinergic agent. Among immunomodulatory treatments, immunotherapy is gaining widespread use, while antibody treatment is restricted mainly to resistant cases. Several small molecules with improved safety profile, or targeting novel mechanisms are in the clinical research. Newer antihistamines and corticosteroids with improved safety profile and antagonists of the prostaglandin D(2) (CRTH2) receptors are likely to be available for clinical use in the near future. Lack of properly validated animal models and complexities associated with clinical evaluation are some of the challenges facing the researchers in AR. Comprehensive understanding of immunological and neurological processes in AR would facilitate the future quest for more effective and safer management of this disease.

Treatment of congestion in upper respiratory diseases

Congestion, as a symptom of upper respiratory tract diseases including seasonal and perennial allergic rhinitis, acute and chronic rhinosinusitis, and nasal polyposis, is principally caused by mucosal inflammation. Though effective pharmacotherapy options exist, no agent is universally efficacious; therapeutic decisions must account for individual patient preferences. Oral H₁-antihistamines, though effective for the common symptoms of allergic rhinitis, have modest decongestant action, as do leukotriene receptor antagonists. Intranasal antihistamines appear to improve congestion better than oral forms. Topical decongestants reduce congestion associated with allergic rhinitis, but local adverse effects make them unsuitable for long-term use. Oral decongestants show some efficacy against congestion in allergic rhinitis and the common cold, and can be combined with oral antihistamines. Intranasal corticosteroids have broad anti-inflammatory activities, are the most potent long-term pharmacologic treatment of congestion associated with allergic rhinitis, and show some congestion relief in rhinosinusitis and nasal polyposis. Immunotherapy and surgery may be used in some cases refractory to pharmacotherapy. Steps in congestion management include (1) diagnosis of the cause(s), (2) patient education and monitoring, (3) avoidance of environmental triggers where possible, (4) pharmacotherapy, and (5) immunotherapy (for patients with allergic rhinitis) or surgery for patients whose condition is otherwise uncontrolled.

Capsaicin treatment of idiopathic rhinitis: the new panacea?

The management of patients with perennial nonallergic or idiopathic rhinitis is difficult. Diagnosis and treatment are hampered by several factors. First, the diagnosis is made by exclusion of other nasal diseases. As a consequence, idiopathic rhinitis is not defined according to clear-cut criteria. A commonly accepted phenotype of idiopathic rhinitis does not exist. Second, the pathophysiology of idiopathic rhinitis is not yet fully elucidated. In contrast with allergic rhinitis, inflammation does not appear to play an important role in idiopathic rhinitis. Recent studies indicate a neural dysregulation of the nasal mucosa. Additionally, the available therapeutic arsenal comprising both pharmacotherapy and surgery is at best partially efficacious in these patients. The efficacy of repeated capsaicin application has been established in several randomized controlled trials. This treatment modality may be the first step to more specific and better treatment options for patients with idiopathic rhinitis that is unresponsive to standard treatment.

Capsaicin for allergic rhinitis in adults

BACKGROUND

Allergic rhinitis represents a global health problem. Non-specific nasal hyperresponsiveness is an important feature of allergic and non-allergic rhinitis. This phenomenon is believed to result from the effect of allergic inflammation on the sensory nerves that supply the upper airway mucosa. A pharmacologic agent that has proved useful in the investigation of effects of neuronal stimulation is capsaicin, the pungent component of hot pepper. Intranasal capsaicin specifically stimulates afferent nerves consisting mostly of unmyelinated C fibers and some myelinated A-delta fibers. As a result it can trigger central and axonal reflexes, the latter being putatively mediated by the release of neuropeptides. Capsaicin as a blocking agent of neuropeptides, blocks the axon reflex and may exert a curative effect on allergic rhinitis.

OBJECTIVES

To assess the effectiveness of capsaicin for allergic rhinitis in adults.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to 2006) and EMBASE (1974 to 2006). We assessed bibliographies from included studies, and contacted authors of known studies for additional information about published and unpublished trials. The date of the most recent search was January 2006.

SELECTION CRITERIA

Randomised controlled trials of capsaicin for allergic rhinitis in adults were included.

DATA COLLECTION AND ANALYSIS

Three reviewers read each paper, blind to its identity. Decisions concerning inclusion were made by simple majority. We all performed quality assessment independently.

MAIN RESULTS

One small trial did not find evidence that intranasal capsaicin had a therapeutic effect in allergic rhinitis. A small pharmacological effect on clinical histamine dose response was found. After treatment, leukotriene levels in nasal lavage did not increase in the capsaicin group.

AUTHORS' CONCLUSIONS

There is insufficient evidence to assess the use of capsaicin in clinical practice.

Randomized, double-blind, placebo-controlled study of montelukast for treating perennial allergic rhinitis

BACKGROUND

Perennial allergic rhinitis (PAR) is a persistent allergic inflammation of the upper respiratory tract due to year-round allergen exposure.

OBJECTIVE

To evaluate the leukotriene receptor antagonist montelukast for the treatment of PAR.

METHODS

Protocol 265 was a 2-arm study performed during the winter. After a placebo run-in period, adults with perennial allergen sensitivity and active symptoms of PAR were randomized to receive 10 mg of montelukast (n=1002) or placebo (n=990) once daily during a 6-week, double-blind, active-treatment period. The primary end point was the daytime nasal symptoms score, defined as the average of scores for nasal congestion, rhinorrhea, and sneezing rated daily by patients.

RESULTS

Statistically significant improvements in PAR symptoms were seen in patients treated with montelukast. Their daytime nasal symptoms scores were reduced during treatment compared with those of the placebo group: the difference between treatments in least squares mean change from baseline was -0.08 (95% confidence interval [CI], -0.12 to -0.04; P < .001). Montelukast treatment also improved global evaluations of allergic rhinitis by patients and Rhinoconjunctivitis Quality of Life Questionnaire scores: differences vs the placebo group were -0.15 (95% CI, -0.27 to -0.04; P < .01) and -0.15 (95% CI, -0.24 to -0.06; P < .001), respectively. Other end points that showed statistically significant improvement with montelukast treatment were nighttime symptoms and each of the 4 nasal symptoms (congestion, rhinorrhea, sneezing, and itching). The treatment effects of montelukast were stable and persistent during the entire 6 weeks of treatment.

CONCLUSION

Montelukast provided statistically significant relief of PAR symptoms during 6 weeks of treatment.

Immunological functions of soy sauce: hypoallergenicity and antiallergic activity of soy sauce

Soy sauce is a traditional fermented seasoning of East Asian countries and is available throughout the world. In Japanese soy sauce (shoyu), soybeans and wheat are the two main raw materials, used in almost the same quantity. Proteins of the raw materials are completely degraded into peptides and amino acids by microbial proteolytic enzymes after fermentation, and no allergens of the raw materials are present in soy sauce. In contrast, polysaccharides originating from the cell wall of soybeans are resistant to enzymatic hydrolyses. These polysaccharides are present in soy sauce even after fermentation and termed shoyu polysaccharides (SPS). Soy sauce generally contains about 1% (w/v) SPS and SPS exhibit potent antiallergic activities in vitro and in vivo. Furthermore, an oral supplementation of SPS is an effective intervention for patients with allergic rhinitis in two double-blind placebo-controlled clinical studies. In conclusion, soy sauce would be a potentially promising seasoning for the treatment of allergic diseases through food because of its hypoallergenicity and antiallergic activity.

Idiopathic rhinitis, the ongoing quest

The term rhinitis in daily practice is used for nasal dysfunction causing symptoms-like nasal itching, sneezing, rhinorrhea and or nasal blockage. Chronic rhinitis can roughly be classified into allergic, infectious or nonallergic/noninfectious. When allergy, mechanical obstruction and infections have been excluded as the cause of rhinitis, a number of poorly defined nasal conditions of partly unknown aetiology and pathophysiology remain. The differential diagnosis of nonallergic noninfectious rhinitis is extensive. Although the percentage of patients with nonallergic noninfectious rhinitis with a known cause has increased the last decades, still about 50% of the patients with nonallergic noninfectious rhinitis has to be classified as suffering from idiopathic rhinitis (IR), or rather e causa ignota. Specific immunological, clinical and sometimes radiological and functional tests are required to distinguish known causes. Research to the underlying pathophysiology of IR has moved from autonomic neural dysbalans to inflammatory disorders (local allergy), the nonadrenergic noncholinergic (NANC) sensory peptidergic neural system and central neural hyperaesthesia, still without solid ground or proof. This review summarizes the currently known causes for nonallergic noninfectious rhinitis and possible treatments. Also possible pathophysiological mechanisms of IR are discussed.

Evaluation of impermeable covers for bedding in patients with allergic rhinitis

BACKGROUND

Encasing bedding in impermeable covers reduces exposure to house-dust mites, but the clinical benefit of this intervention as part of mite-avoidance measures for patients with allergic rhinitis is not known. We performed a multicenter, randomized, placebo-controlled trial of one year of use of impermeable bedding covers in the bedrooms of patients with rhinitis who were sensitized to house-dust mites to determine the effects on the signs and symptoms of disease.

METHODS

Three participating university medical centers enrolled 279 patients with allergic rhinitis who were randomly assigned to receive impermeable or non-impermeable (control) covers for their mattress, pillow, and duvet or blanket. At the start of the study, all participants received information on general allergen-avoidance measures. The severity of rhinitis was measured on a rhinitis-specific visual-analogue scale and by means of a daily symptom score and nasal allergen provocation testing. We also measured the concentrations of Dermatophagoides pteronyssinus (Der p1) and D. farinae (Der f1) in dust from patients' mattresses, bedroom floors, and living-room floors at base line and after 12 months as a measure of the efficacy of the intervention.

RESULTS

A total of 232 patients completed the study. There was a significant reduction in Der p1 and Der f1 concentrations in the mattresses of the impermeable-cover group, whereas there was no significant reduction in the control group. However, there was no significant effect on the clinical outcome measures. Analyses of subgroups defined according to age, level of exposure, type and severity of sensitization, or characteristics of the patient's home had similar results.

CONCLUSIONS

Mite-proof bedding covers, as part of a structured allergy-control program, reduced the level of exposure to mite allergens. Despite the success of the intervention, this single avoidance measure did not lead to a significant improvement of clinical symptoms in patients with allergic rhinitis.

Anti-inflammatory actions of acupuncture

Acupuncture has a beneficial effect when treating many diseases and painful conditions, and therefore is thought to be useful as a complementary therapy or to replace generally accepted pharmacological intervention. The attributive effect of acupuncture has been investigated in inflammatory diseases, including asthma, rhinitis, inflammatory bowel disease, rheumatoid arthritis, epicondylitis, complex regional pain syndrome type 1 and vasculitis. Large randomised trials demonstrating the immediate and sustained effect of acupuncture are missing. Mechanisms underlying the ascribed immunosuppressive actions of acupuncture are reviewed in this communication. The acupuncture-controlled release of neuropeptides from nerve endings and subsequent vasodilative and anti-inflammatory effects through calcitonine gene-related peptide is hypothesised. The complex interactions with substance P, the analgesic contribution of beta-endorphin and the balance between cell-specific pro-inflammatory and anti-inflammatory cytokines tumour necrosis factor-alpha and interleukin-10 are discussed.