Nonallergic rhinitis. Pathophysiology and models for study

Rhinorrhea and increased chloride secretion through the CFTR chloride channel-a systematic review

PURPOSE

Allergic and non-allergic rhinorrhea in the forms of acute or chronic rhinosinusitis can mean a watery nasal discharge that is disabling. Primary objective was to review the evidence supporting the hypothesis that rhinorrhea is due to increased chloride secretion through the CFTR chloride channel.

METHODS

The structure of the evidence review followed the EQUATOR Reporting Guidelines. Databases searched from inception to February 2022 included Pubmed, EMBASE and the Cochrane library using keywords "Rhinorrhea", "chloride", "chloride channel", "CFTR" and "randomized controlled trial". Quality assessment was according to the Oxford Centre for Evidence-based Medicine.

RESULTS

49 articles were included. They included randomized controlled trials out of which subsets of data with the outcome of rhinorrhea on 6038 participants were analysed and in vitro and animal studies. The review revealed that drugs, which activate CFTR are associated with rhinorrhea. Viruses, which cause rhinorrhea like rhinovirus were found to activate CFTR. The chloride concentration in nasal fluid showed an increase in patients with viral upper respiratory tract infection. Increased hydrostatic tissue pressure, which is an activator of CFTR was observed in allergic upper airway inflammation. In this condition exhaled breath condensate chlorine concentration was found to be significantly increased. Drugs, which can reduce CFTR function including steroids, anti-histamines, sympathomimetic and anticholinergic drugs reduced rhinorrhea in randomized controlled trials.

CONCLUSIONS

A model of CFTR activation-mediated rhinorrhea explains the effectiveness of anticholinergic, sympathomimetic, anti-histamine and steroid drugs in reducing rhinorrhea and opens up avenues for further improvement of treatment by already known specific CFTR inhibitors.

Randomised trial on performance, safety and clinical benefit of hyaluronic acid, hyaluronic acid plus dexpanthenol and isotonic saline nasal sprays in patients suffering from dry nose symptoms

OBJECTIVE

Limited data exist on the clinical benefits of nasal applications for moistening the nasal mucosa. We therefore investigated the effects of hyaluronic acid, hyaluronic acid plus dexpanthenol and isotonic saline nasal sprays in patients suffering from dry nose symptoms in an otorhinolaryngological outpatient setting.

METHODS

240 patients were randomised into this prospective, three-armed clinical trial with two assessment points (baseline and 4 weeks later). Patients received either hyaluronic acid, hyaluronic acid plus dexpanthenol or isotonic saline nasal spray over a period of four weeks. Rhinitis Sicca Symptom Score (RSSS) was assessed as primary endpoint, and individual symptoms and tolerability of all treatments as secondary endpoints. Patient perceptions after first application of the allocated nasal spray were recorded using the Nasal Spray Sensory Scale. Treatment effects were analysed for each study arm first and subsequently compared against each other.

RESULTS

RSSS (hyaluronic acid: mean difference = 8.90 [98.33% CI = 7.34/10.45]; hyaluronic acid plus dexpanthenol: mean difference = 8.42 [98.33% CI = 6.91/9.94]; isotonic saline: mean difference = 8.94 [98.33% CI = 7.33/10.54]), individual symptoms and Endoscopy Score improved significantly (p < 0.001) in all treatment arms. Tolerability was assessed as "flawless" in more than 85% of all treatments, which is reflected in overall high rankings in the Nasal Spray Sensory Scale. Perception of nasal moisturisation was reported to be significantly higher in patients receiving hyaluronic acid plus dexpanthenol as compared to patients receiving hyaluronic acid or isotonic saline. No further significant differences were observed between the three treatments.

CONCLUSION

All three tested sprays (hyaluronic acid, hyaluronic acid plus dexpanthenol and isotonic saline) proved to be suitable treatments for patients suffering from dry nose symptoms. (DRKS-ID: DRKS00013357).

Nonallergic Rhinitis: Treatment

Chronic nonallergic rhinitis (NAR) is a syndrome rather than a specific disease. A lack of understanding of the pathogenesis of this condition has led to imprecise terminology with several alternate names for the condition, including vasomotor rhinitis, nonallergic rhinopathy, and idiopathic rhinitis. The therapy for NAR is best based on the underlying pathology, which typically exists in a form whereby an abnormality of the autonomic nervous system is dominant or a form in which inflammation seems to be the cause of symptoms. In general the most effective therapy is the combination of an intranasal antihistamine and an intranasal corticosteroid.

Nasal histamine responses in nonallergic rhinitis with eosinophilic syndrome

Background:

Nonallergic rhinitis with eosinophilic syndrome (NARES) is persistent, without atopy, but with ≥25% nasal eosinophilia. Hypereosinophilia seems to contribute to nasal mucosa dysfunction.

Objectives:

This analytical case-control study aimed at assessing the presence and severity of nonspecific nasal hyperactivity and at finding out whether eosinophilia may be correlated with the respiratory and mucociliary clearance functions.

Materials:

The symptom score was assessed in 38 patients and 15 controls whose nasal smear was also tested for eosinophils and mucociliary transport (MCT). Nonspecific nasal provocation tests (NSNPT) with histamine were also carried out, and total nasal resistance (TNR) was determined.

Results:

The symptom score of NARES after NSNPT were not significantly different from the control group, and there was poor or no correlation among the single symptoms and the differences studied for every nasal reactivity class. This correlation improved when using the composite symptom score. The most severe eosinophilia was observed in high reactivity groups, and it was correlated with an increase in TNR. MCT worsened as eosinophilia and nasal reactivity increased. Unlike controls, a significant correlation was observed between the increase in MCT and TNR.

Conclusions:

In NARES, nonspecific nasal hyperreactivity is the result of epithelial damage produced by eosinophilic inflammation, which causes MCT slow down, an increase in TNR, and nasal reactivity classes, with possible impact on classification, prognosis, and treatment control.

Nonallergic rhinitis

Rhinitis is normally defined by the symptoms of nasal congestion, postnasal drainage, rhinorrhea, and sneezing. It has been associated with various pathologic changes, but can occur in the absence of any inflammation. Thus, the diagnosis is based on the clinical presentation. There are no clear-cut criteria to distinguish when rhinitis becomes chronic, but in its chronic form, it can be complex. Chronic forms of rhinitis that occur in the absence of any detectable specific IgE against relevant aeroallergens in its broadest sense can be called chronic nonallergic rhinitis. This review will concentrate on chronic nonallergic rhinitis in its various forms, discussing the epidemiology, underlying mechanisms, and its therapy.

Tonic stimulation of the pharyngeal mucosa causes pain and a reversible increase of inflammatory mediators

Objective and design

To develop a model of the inflammatory component of non-infectious sore throat using tonic stimulation and quantification of inflammatory mediators in pharyngeal lavage fluid.

Material or subjects

Forty-five healthy volunteers.

Treatment

Cold dry air.

Method

Tonic stimulation of the pharynx was achieved using a constant stream of cold dry air to the back of the throat. Following optimization of stimulation conditions (phase 1), pharyngeal pain, irritation, and swallowing discomfort were assessed using visual analog scales, and the concentration of inflammatory markers were measured in pharyngeal lavage fluid (phase 2).

Results

Optimum conditions for tonic pharyngeal stimulation were cold dry air at 12 °C, relative humidity 20 %, at a flow rate of 12 L/min for 15 min. Analysis of pharyngeal lavage fluid collected 5 min after stimulation showed significant increases in prostaglandin E₂ (P = 0.018), thromboxane B₂ (P < 0.001), and substance P (P < 0.001), but no increase in peptidoleukotriene. When the stimulus was removed, the level of inflammatory markers in pharyngeal lavage fluid returned to baseline by 30 min post-stimulation. These objective measures mirrored subjective pain ratings.

Conclusions

Tonic stimulation of the pharyngeal mucosa with cold dry air causes pain and an increase of inflammatory mediators which are reversible.

Electronic supplementary material

The online version of this article (doi:10.1007/s00011-013-0663-7) contains supplementary material, which is available to authorized users.

Nasal obstruction and rhinorrhea reflect nonspecific nasal hyper-reactivity as evaluated by cold dry air provocation

CONCLUSION

Nasal obstruction, rhinorrhea, and the amount of rhinorrhea that confidently reflect the parasympathetic stimulation can be used to more precisely predict nonspecific nasal hyper-reactivity (NHR).

OBJECTIVE

We aimed to identify factors that confidently reflected the presence and the degree of NHR, measured by cold dry air (CDA) provocation and acoustic rhinometry.

METHODS

A total of 156 patients with allergic or non-allergic rhinitis were classified into three groups according to the decrease of minimal cross-sectional area (MCA) after CDA provocation (group A: n = 40, MCA decrease >60%; group B: n = 29, MCA decrease 30-60%; group C: n = 87, MCA decrease <29%). Symptom scores using the visual analog scale (VAS) were obtained before and after CDA provocation. Changes of VAS were compared between groups. The amount of rhinorrhea was measured after CDA provocation.

RESULTS

VAS scores for nasal obstruction, rhinorrhea, and sneezing were significantly higher in groups A and B than in group C before and after CDA provocation. Change of nasal obstruction and rhinorrhea was significantly larger in group A compared with group B or C. There were also significant differences in the amount of rhinorrhea between groups. All these parameters significantly correlated with the change of MCA values after CDA provocation.

Environmental and non-infectious factors in the aetiology of pharyngitis (sore throat)

OBJECTIVES

The aim of this review is to examine the causes, pathophysiology and experimental models of non-infectious pharyngitis (sore throat).

INTRODUCTION

The causes of sore throat can be infectious (viruses, bacteria, and fungi) or non-infectious, although the relative proportion of each is not well documented.

METHODS

A PubMed database search was performed for studies of non-infectious sore throat.

RESULTS AND CONCLUSIONS

Non-infectious causes of sore throat include: physico-chemical factors, such as smoking, snoring, shouting, tracheal intubation, medications, or concomitant illness; and environmental factors including indoor and outdoor air pollutants, temperature and humidity, and hazardous or occupational irritants. The pathophysiology underlying non-infectious sore throat is largely uncharacterised, although neurogenic inflammation looks to be a promising candidate. It is likely that there will be individual disposition factors or the coincidence of more than one irritant with possible--up to now unknown--interactions between them. Therefore, experimental models with defined conditions and objective endpoints are needed. A new model using cold dry air to directly induce pharyngeal irritation in humans, with pharyngeal lavage to measure biomarkers, may provide a useful tool for the study of mechanisms and treatment of non-infectious sore throat.

Subjective cold hyper-responsiveness grade reflects age- and duration-related increase of nonspecific nasal hyperreactivity

OBJECTIVE

We evaluated the effect of patients' age and duration of allergic rhinitis on nonspecific nasal hyper-reactivity (NHR) using cold dry air (CDA) provocation.

METHODS

In 156 patients of various ages with allergic rhinitis and different symptom duration, we evaluated the change of symptoms, the subjective cold hyper-responsiveness (SCH) grade, the change of acoustic parameters such as total nasal volume (TNV) and minimal cross-sectional area (MCA), and the amount of rhinorrhea before and after CDA provocation.

RESULTS

Patients in different age or duration groups did not show significant differences in the change of each nasal symptom. SCH grade 2 or 3 was more frequently observed in patients older than 30 years (p=0.018). There was a significant correlation between the age of the patients and the SCH grade (R=0.184, p=0.022). Patients with >10 years of duration reported higher SCH grade (p=0.022). There was a significant correlation between the duration of disease and SCH grade (R=0.284, p<0.001). However, there were no significant differences in the change of TNV and MCA, and the amount of rhinorrhea after CDA provocation between different age and duration groups.

CONCLUSION

SCH grade reflects the age- and duration-related increase of NHR. Further studies to elucidate the pathophysiologic mechanisms are needed in the future.

Phytomedicine in otorhinolaryngology and pulmonology: clinical trials with herbal remedies

Phytomedicine has become an important alternative treatment option for patients in the Western world, as they seek to be treated in a holistic and natural way after an unsatisfactory response to conventional drugs. Ever since herbal remedies have been introduced in the Western world, clinicians have raised concerns over their efficacy and possible side-effects. A PubMed (Medline) search was performed covering the last five years (01/07-04/12) and including 55 prospective clinical randomized control trials in the medical specialities Otorhinolaryngology and Pulmonology. In this review, we present evidence-based clinical data with herbal remedies and try to enlighten the question of efficacy and reliability of phytomedicine.

Usefulness of the subjective cold hyperresponsiveness scale as evaluated by cold dry air provocation

BACKGROUND

There is still no study about the correlation between the symptom score and the reactivity to cold dry air (CDA). The authors developed a subjective cold hyperresponsiveness (SCH) scale for CDA and we evaluated its usefulness by comparing the changes of the symptom score and the acoustic parameters between different SCH groups and analyzing the correlation between the SCH scale and other parameters.

METHODS

One hundred fifty-two patients were classified according to their SCH scale. The symptom score by the visual analog scale (VAS), the total nasal volume (TNV), and the minimal cross-sectional area (MCA) by acoustic rhinometry were obtained before and after CDA provocation. Changes of these values were compared between groups and an analysis was performed for the correlation between SCH scale and change of the VAS, TNV, or MCA.

RESULTS

The patients with SCH grade 2 or 3 had a greater change of the VAS scores for nasal obstruction and rhinorrhea. The patients with SCH grade 2 or 3 had a greater change of the TNV (grade 0, 26.1 ± 17.2%; grade 1, 33.3 ± 26.5%, versus grade 2, 44.2 ± 30.0%; grade 3, 61.6 ± 40.0%; p < 0.05) and MCA (grade 0, 23.0 ± 25.3%; grade 1, 35.7 ± 51.1%, versus grade 2, 61.2 ± 72.4%; grade 3, 80.5 ± 56.4%; p < 0.05). Significant correlation existed between the SCH scale and changes in the TNV or MCA.

CONCLUSION

We developed the SCH scale and proved its usefulness for evaluating nonspecific hyperreactivity.

Inflammatory Cell Patterns in the Nasal Mucosa of Patients with Idiopathic Rhinitis

Background

Nonallergic rhinitis comprises many subgroups of rhinitis (vasomotor rhinitis, nonallergic rhinitis with eosinophilia syndrome, occupational rhinitis, idiopathic rhinitis, etc. in which its main feature is known to be free of allergy. We evaluate the cellular infiltrate of subjects with idiopathic rhinitis and compare them with allergic and control counterparts for detecting underlying pathophysiology.

Methods

Subjects selected from patients admitted to Istanbul University Medical Faculty between 2006 and 2009 were classified into idiopathic rhinitis (n = 16; mean age, 26.5 years), allergic rhinitis (n = 17; mean age, 31.1 years), and the control (n = 25, mean age, 28.8 years) groups. Inferior turbinate specimens were collected using Gerritsma forceps. Skin-prick testing was performed. Immunohistochemical detection was performed using B7 (chymase, clone CC1) and G3 (tryptase, clone AA1) primary antibodies for mast cells, human eosinophil major basic protein (clone BMK-13) for eosinophils, and immunoglobulin E (IgE) Ab-1 for mast and plasma cells in epithelium, superficial, and deep submucosa.

Results

We found significantly higher levels of mast cells within the different sites of nasal mucosa of allergic and idiopathic subjects compared with normal mucosa (p < 0.05). Additionally, a significant increase was observed in IgE+ cells of the patients with allergic and idiopathic rhinitis compared with the controls (p < 0.05 for each) Eosinophils were significantly increased within the epithelium of allergic patients’ mucosa.

Conclusion

We seem to have supportive data about possible mechanisms of “idiopathic rhinitis” that suggests local allergic inflammation. The study results provided important information for further provocation and immunohistochemical studies analyzing the shared mechanism of allergic and idiopathic rhinitis.

Use of cold dry air provocation with acoustic rhinometry in detecting nonspecific nasal hyperreactivity

BACKGROUND

Cold dry air provocation is useful for evaluating nonspecific nasal hyperreactivity. However, there is no research on nasal volume and dimensions after cold dry air provocation. In this respect, acoustic rhinometry is a useful tool in objectively assessing nasal cavity volume and dimension. The goal of this study was to evaluate nonspecific hyperreactivity using cold dry air provocation with acoustic rhinometry.

METHODS

Cold dry air provocation with acoustic rhinometry was performed on 21 healthy volunteers (group A), 24 patients with allergic rhinitis (group B), and 32 patients with nonallergic rhinitis (group C). The change in symptoms using a visual analog scale (VAS), amount of rhinorrhea, and change of total nasal volume (TNV) and minimal cross-sectional area (MCA) were measured in all three groups.

RESULTS

The two patient groups showed greater change in nasal symptoms (VAS, 2.0 +/- 2.3 in group C versus 0.9 +/- 1.8 in group A), more rhinorrhea (0.4 +/- 0.7 g in group B and 0.3 +/- 0.3 g in group C versus 0.1 +/- 0.1 g in group A), and greater change in total nasal volume (TNV) and MCA. The patient group with history of nonspecific hyperreactivity showed more rhinorrhea (0.5 +/- 0.7 g versus 0.1 +/- 0.2 g) and greater change in TNV and MCA (TNV, 56.8 +/- 39.5% versus 18.0 +/- 17.0%; MCA, 86.6 +/- 81.0% versus 11.5 +/- 9.7%).

CONCLUSION

Cold dry air provocation with acoustic rhinometry could be a useful adjunct tool for detecting nonspecific hyperreactivity.

Diagnostic Criteria of Nonspecific Hyperreactivity Using Cold Dry Air Provocation With Acoustic Rhinometry

Objective. The authors aimed to (1) compare symptom changes in patients with or without nonspecific hyperreactivity, (2) compare changes in total nasal volume (TNV) and minimal cross-sectional area (MCA) using acoustic rhinometry after cold dry air (CDA) challenge, and (3) set the diagnostic criteria using receiver operating characteristic (ROC) curve analysis.

Study Design. Prospective pilot.

Setting. Academic tertiary rhinologic practice.

Subjects and Methods. CDA provocation was performed on 45 patients with self-reported hypersensitivity to cold dry air (group A) and to 53 patients without such hypersensitivity (group B). Symptoms (as measured by visual analog scale [VAS]), TNV, and MCA were checked before and after provocation.

Results. The changes in nasal obstruction (1.8 ± 2.1 vs 0.0 ± 2.3) and rhinorrhea (0.8 ± 2.1 vs −0.5 ± 2.3) were significantly greater in group A ( P < .01 in each case). There were no significant differences between groups in VAS scores for sneezing and itching. From the ROC curve, the authors set the diagnostic criterion as “TNSS (total nasal symptom score) change larger than 1.5,” and its sensitivity and specificity were 75.6% and 86.8%, respectively. The criteria “TNV decrease larger than 19.5%” and “MCA change larger than 15.0%” had higher sensitivity and specificity (TNV: 84.4% sensitivity and 77.4% specificity; MCA: 93.3% sensitivity and 77.4% specificity).

Conclusions. The authors were able to propose diagnostic criteria of nonspecific hyperreactivity using a CDA provocation test with acoustic rhinometry. These results are also helpful for understanding the pathophysiologic mechanisms of nonspecific hyperreactivity.

Vasomotor rhinitis

Vasomotor rhinitis is a common disorder that is seen routinely in allergy practice. It affects millions of Americans and results in significant morbidity. The pathophysiology of this complex heterogeneous disorder is unknown, but we are making advances in this regard. Symptoms and signs can closely resemble those of allergic rhinitis and can be difficult to differentiate from those resulting from allergy. A careful history, physical examination, and diagnostic testing help clinicians arrive at a definitive diagnosis, but treatment can be challenging. Therapy should be based on the presenting symptoms of vasomotor rhinitis. Combination therapy with topical corticosteroids and azelastine is useful. However, in patients whose predominant symptom is rhinorrhea, use of atopical anticholinergic agents can be quite useful. Up-to-date pathogenesis, epidemiology, diagnosis, and treatment approaches are discussed in this review.

Genes regulating molecular and cellular functions in noninfectious nonallergic rhinitis

BACKGROUND

Chronic noninfectious, nonallergic rhinitis (NINAR) is a complex syndrome with a principally unknown pathophysiology. New technology has made it possible to examine differentially expressed genes and according to network theory, genes connected by their function that might have key roles in the disease.

METHODS

Connectivity analysis was used to identify NINAR key genes. mRNA was extracted from nasal biopsies from 12 NINAR patients and 12 healthy volunteers. Microarrays were performed using Affymetrix chips with 54 613 genes. Data were analysed with the Ingenuity Pathway System for organization of genes into annotated biological functions and, thereafter, linking genes into networks due to their connectivity. The regulation of key genes was confirmed with reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

In all, 43 genes were differentially expressed. The functional analysis showed that these genes were primarily involved in cellular movement, haematological system development and immune response. Merging these functions, 10 genes were found to be shared. Network analysis generated three networks and two of these 'shared genes' in key positions, c-fos and cell division cycle 42 (Cdc42). These genes were upregulated in both the array and the RT-PCR analysis.

CONCLUSION

Ten genes were found to be of pathophysiological interest for NINAR and of these, c-fos and Cdc42 seemed to be of specific interest due to their ability to interact with other genes of interest within this context. Although the role of c-fos and Cdc42 in upper airway inflammation remains unknown, they might be used as potential disease markers.

Intranasal Capsicum spray in idiopathic rhinitis: a randomized prospective application regimen trial

CONCLUSION

Local Capsicum oleous nasal spray, 4 microg/puff three times a day for 3 consecutive days, is an efficacious and safe treatment for idiopathic rhinitis (IR). Furthermore, being a natural product, Capsicum oleous nasal spray may be readily available for patients.

OBJECTIVES

To evaluate the efficacy and safety of different therapeutic regimens of Capsicum oleous nasal spray in IR.

PATIENTS AND METHODS

A total of 208 patients affected by IR were enrolled in a randomized placebo-controlled trial. Diagnosis of IR was made on the basis of history of nasal obstruction, sneezing and/or rhinorrhoea and after exclusion of other nasal/paranasal anatomic disorders. IR patients were randomized into four groups (groups A, B, and C) receiving increasing doses of Capsicum (1, 2 or 4 microg/puff, respectively) and one group (group D) treated with placebo. Capsicum oleous nasal spray, one puff per nostril, was instilled three times a day at 30 min intervals for 3 consecutive days. Pre- and post-treatment nasal symptoms were evaluated with a daily record chart.

RESULTS

A significant reduction in the frequency of IR symptom was noticed in group C (4 microg/puff, three times a day for 3 consecutive days) vs controls (p=0.003). No significant difference in side effects was recorded in patients receiving Capsicum therapy with respect to controls.

Reverse association between high-altitude headache and nasal congestion

No evidence is available to show that nasal congestion is a manifestation of exposing an individual to high altitude and hypoxia. Since both nasal congestion and high-altitude headache are vasogenic, we explored whether there is a coincidence between these two symptoms. A prospective observational study was carried out on a cohort of 118 adults (>18 years old) in a mountain clinic at 3450 m. After 24 h of ascent, an interview was held to ask if each individual experienced acute mountain sickness symptoms (headache, etc.) and nasal congestion. Sixty-six (55.9%) individuals mentioned headache within 24 h after ascent and nasal congestion was reported by 34 (28.8%) individuals. There was a reverse association between headache and nasal congestion (P < 0.001). In conclusion, there is a reverse association between altitude headache and nasal congestion, probably as result of contradictory autoregulation effects or exaggerated sympathetic activity.

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.

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.

Interleukin (IL)-4 and to a lesser extent either IL-13 or interferon-gamma regulate the production of eotaxin-2/CCL24 in nasal polyps

BACKGROUND

Eotaxin-2/CCL24 is a potent eosinophil attractant that has been implicated in the recruitment of eosinophils in allergic disease. We have investigated whether the cytokines interleukin (IL)-4, IL-13, and interferon (IFN)-gamma regulate eotaxin-2/CCL24 in nasal polyps.

METHODS

Nasal polyps were cultured in the presence of the cytokines described above and the concentration of eotaxin-2/CCL24 was measured in the culture supernatant.

RESULTS

IL-4 was found to be the major stimulus for eotaxin-2/CCL24 production from nasal polyps followed by IL-13 and IFN-gamma. IL-4 induced eotaxin-2/CCL24 in a dose-dependent manner with concentrations as low as 0.1 ng/ml being able to induce eotaxin-2/CCL24. By immunohistochemistry, eotaxin-2/CCL24 immunoreactivity was localized to mononuclear cells in the IL-4 stimulated nasal polyp tissue. Interestingly, nasal turbinates obtained from patients suffering from nonallergic rhinitis (vasomotor rhinitis) were also found to release eotaxin-2/CCL24 both spontaneously and following cytokine stimulation with IL-4 and IFN-gamma being major inducers of this cytokine.

CONCLUSIONS

All together these findings suggest that Th1 and Th2 cytokines may regulate eotaxin-2/CCL24 production in nasal polyps and nonallergic rhinits.

Intranasal capsaicin reduces nasal hyperreactivity in idiopathic rhinitis: a double-blind randomized application regimen study

BACKGROUND

In a recent study, we showed that intranasal capsaicin spray gives a significant and long-term reduction of symptoms in nonallergic noninfectious perennial rhinitis patients. However, in daily practice, the studied application regimen proved to be impractical because of the large number of visits required in a short period of time. In the present study, we conducted a double-blind double-dummy parallel groups trial to determine whether a more practical capsaicin application schedule is equally effective.

METHODS

Thirty patients were randomized into two different treatment regimens: one group received capsaicin five times on the first day at 1-h intervals. This was followed by a placebo dummy once every second or third day for a total of five treatments 2 weeks after the capsaicin application (group A). The other group (B) received the placebo dummy five times on the first day followed by capsaicin once every second or third day for a total of five treatments 2 weeks after the placebo application.

RESULTS

The visual analogue scale scores for overall nasal symptoms, rhinorrhea and nasal blockage showed significant decrease after the start of treatment in both groups, with a significantly steeper decrease in group A. A significant reduction in cold dry air dose responsiveness was also found up to 9 months after therapy in both groups, reflecting a decrease in nasal hyperreactivity. No significant changes in safety data (smell, blood pressure, heart rate) were found.

CONCLUSIONS

We conclude that intranasal capsaicin seems safe to use and that five treatments of capsaicin on a single day is at least as effective as five treatments of capsaicin in 2 weeks.

Pain in the trigeminal system: irritation of the nasal mucosa using short- and long-lasting stimuli

The paper describes methods which allow intranasal irritation using short- and long-lasting painful stimuli in humans. Short-lasting pain is induced by gaseous CO(2), while long-lasting pain is induced by a stream of dry air. Both models have been explored regarding their major determinants, e.g. stimulus duration, stimulus intensity, or repeated stimulation. Short-lasting, non-inflammatory pain stimuli seem to provide specific indicators of A(delta)-fiber function, while responses to long-lasting, inflammatory pain appear to be indicative of C-fiber function. Responses to both types of painful stimuli are modulated by analgesic drugs. As these well-investigated models allow the detailed and precise analysis of modulatory effects on intranasal nociception, they appear to be suited for the investigation of subtle changes of intranasal irritation, e.g. induced by environmental agents.

Intranasal capsaicin is efficacious in non-allergic, non-infectious perennial rhinitis. A placebo-controlled study

BACKGROUND

Several authors described capsaicin, the pungent substance in red pepper, as an efficacious therapy for non-allergic non-infectious perennial rhinitis (NANIPER). Repeated capsaicin application induces peptide depletion and specific degeneration of the unmyelinated sensory C-fibres in the nasal mucosa.

METHODS

We performed a placebo-controlled (NaCl 0.9%) study with 25 NANIPER patients. Daily record charts and visual analogue scales (VAS) were used for clinical evaluation. Nasal lavages were obtained before, during, and after treatment.

RESULTS

There was a significant and long-term reduction in the VAS scores in the capsaicin group. No significant difference was found between the placebo and capsaicin treated groups for the mean group concentrations of leukotriene (LT) C4/D4/E4, prostaglandin D2 (PGD2), and tryptase. The levels of mast cell mediators, tryptase and PGD2, and leukotrienes, mediators derived from a variety of inflammatory cells, were low at baseline and comparable with levels observed in nasal lavages obtained from normals.

CONCLUSION

As involvement of inflammation could not be demonstrated, it is not surprising that capsaicin has no effect on inflammatory mediators. This suggests that inflammatory cells do not play a major part in the pathogenesis of NANIPER.