A mouse model of acute bacterial rhinosinusitis

OBJECTIVE

To develop a mouse model of acute bacterial rhinosinusitis.

DESIGN

Study mice (C57BL6/J) were inoculated intranasally with Streptococcus pneumoniae, ATCC 49619 suspended in trypticase soy broth, and controls were inoculated with trypticase soy broth alone. After 2, 5, or 14 days, intranasal cultures were obtained and mice were killed. The sinuses were prepared for histological investigation.

SETTING

Animal care facility at a tertiary, academic institution.

METHOD

The histological sections of the sinuses were examined in a blinded manner for the percentage of sinus cavity occupied by neutrophil clusters, and for the number of neutrophils per square millimeter of sinus mucosa.

RESULTS

Infected mice killed at 5 days had significantly more sinus area occupied by neutrophil clusters, significantly more neutrophils within the mucosa, and significantly more S pneumoniae growth in the intranasal cultures compared with controls (15/15 vs 0/6; P<.01). The amount of inflammation had decreased at 2 weeks.

CONCLUSION

Streptococcus pneumoniae induces acute bacterial rhinosinusitis in C57BL6/4 mice as measured by culture and influx of neutrophils, and can be used as a model of acute bacterial rhinosinusitis.

Intranasal beclomethasone reduces allergen-induced symptoms and superficial mucosal eosinophilia without affecting submucosal inflammation

Previous investigations have suggested that nasal secretions, obtained by lavage or scraping, and the nasal submucosa, sampled by biopsy, are two distinct compartments. We investigated the effect of intranasal corticosteroids on antigen-induced eosinophil influx into both compartments. We performed a double-blind, placebo-controlled study in 15 patients with seasonal allergic rhinitis. Beclomethasone dipropionate, 84 microg twice a day, was delivered to one nostril while the other nostril received placebo for 1 wk. Subjects were then challenged with grass or ragweed extracts on each inferior turbinate. Nasal scrapings from both inferior turbinates were obtained before and 24 h after challenge, and bilateral inferior turbinate biopsies were obtained 24 h after challenge, with the subjects still receiving treatment. Intranasal steroids led to a significant reduction in sneezes and eosinophil influx in nasal secretions without affecting the number of eosinophils in the submucosa. Furthermore, intranasal steroids had no effect on the numbers of submucosal EG2+ (activated eosinophils) or CD25+ (IL-2-receptor-bearing) cells, nor did they decrease the endothelial expression of vascular cell adhesion molecule-1 (VCAM-1). These data show that pretreatment with intranasal steroids successfully inhibited the clinical response to allergen and reduced eosinophils in the superficial compartment of the nasal mucosa, but it had no effect on inflammation in the deeper compartment. This might be related to a different distribution of the active medication and antigen into the nasal mucosa or to a specific effect of the active medication on the epithelium resulting in inhibited migration of eosinophils across this layer.

Effect of enantiomeric forms of albuterol on stimulated secretion of granular protein from human eosinophils

We studied the effect of R-, S- and R,S-albuterol in inhibiting the eosinophil peroxidase (EPO) secretion caused by 10(-10) to 10(-6) M formyl-met-leu-phe + 5 micrograms/ml cytochalasin B (FMLP/CB) in non-allergic and allergic subjects. Total RAST score obtained for allergic subjects was 4.12 +/- 0.21 vs 0.36 +/- 0.17 for non-allergic subjects (P < 0.0001). Stimulated EPO secretion was comparable in allergic [2,051 +/- 567 ng/10(6) eosinophils (eos)] and non-allergic subjects [2,337 +/- 488 ng/10(6) eos (P = NS)]. At all concentrations used, both R- and R,S-enantiomers caused comparable (27-32%) inhibition of FMLP/CB stimulated secretion of EPO in allergic and non-allergic subjects. Pretreatment with S-albuterol caused no augmentation of EPO secretion in either allergic (115 +/- 34.6%) or non-allergic subjects (114 +/- 23.7%) subjects, and there was no significant difference in secretion caused by FMLP/CB alone in either experimental group. Similar results were obtained for subjects stratified according to serum IgE concentration. Our data demonstrate that both R- and R,S-albuterol are equivalently effective in inhibiting stimulated secretion of EPO in both normal and allergic subjects and that there is no paradoxical augmenting effect of S-albuterol in stimulated eosinophil secretion.

Comparison of nasal mucosal responsiveness to neuronal stimulation in non-allergic and allergic rhinitis: effects of capsaicin nasal challenge

BACKGROUND

Neuronal involvement has been implicated in the pathophysiology of non-allergic and allergic rhinitis, contributing to the typical exacerbation of these conditions upon exposure to non-specific environmental irritants.

OBJECTIVES

To determine if non-allergic and allergic rhinitis are characterized by increased responsiveness of the nasal mucosa to sensorineural stimulation.

METHODS

Nasal challenges with capsaicin and its vehicle were performed in three groups of subjects -- non-allergic rhinitics, perennial allergic rhinitics, and healthy controls -- and resultant symptom scores, glandular secretion reflected by lactoferrin levels, and plasma extravasation reflected by albumin levels in nasal lavage fluid were compared.

RESULTS

Capsaicin-sensitive nerve stimulation produced increases in symptom scores and lactoferrin levels which were similar among the three groups of subjects. On the other hand, only the group of subjects with allergic rhinitis demonstrated a significant capsaicin-induced increase in albumin levels and a trend in total protein levels.

CONCLUSIONS

We conclude that non-allergic rhinitis is not characterized by increased responsiveness of capsaicin-sensitive nerve fibres; while allergic rhinitis is marked by hyperresponsiveness manifested as increased albumin leakage in nasal fluids. This may reflect the activity of an axonal reflex to sensorineural stimulation.

Nasal provocation with allergen induces a secondary serum IgE antibody response

The study of the IgE response to seasonal antigen exposure is limited by its occurrence once a year and by the variability of patient exposure to pollens. To overcome these problems, we investigated whether nasal challenge with antigen causes an increase in serum anti-ragweed IgE levels. We challenged individuals with ragweed allergy intranasally with nanogram quantities of ragweed antigen extract and measured their serum anti-ragweed IgE levels before and at weekly intervals after challenge. In a series of studies we found that there was a reproducible rise in antigen-specific serum IgE levels beginning the first week after challenge that plateaued at about 180% of baseline levels during the fourth week and remained elevated for 8 weeks. Not all individuals showed this response. The magnitude of the allergen-specific IgE response to nasal challenge appeared to be greater than the response to seasonal exposure. Treatment with intranasal beclomethasone before challenge did not affect the response. The results demonstrate a human in vivo model for the study of the antigen-specific secondary IgE response to allergen.

Total IgE serum levels correlate with sinus mucosal thickness on computerized tomography scans

BACKGROUND

Sinusitis involves an inflammatory response with similarities to asthma.

OBJECTIVE

We sought to determine whether a correlation exists between total IgE and the sinus mucosal thickening as assessed by computed tomography (CT) scans.

METHODS

We screened the charts of 300 otolaryngology patients who had total and specific serum IgE determinations in 1994 and from this group selected all patients who had also undergone a sinus CT scan close to the time of serum evaluation (n = 86). Severity of disease on CT scan was graded by two investigators blinded to IgE levels.

RESULTS

There was a significant positive correlation between severity of disease on CT scans and IgE (r[s] = 0.37, p = 0.0007). Furthermore, patients with a more advanced disease stage had higher IgE levels. There was also a positive correlation between severity of disease and the sum of specific IgE grades (r[s] = 0.29, p = 0.007).

CONCLUSION

The data suggest that IgE levels or a linked genetic parameter may contribute to the mucosal inflammation in the paranasal sinuses.

A double-blind study of the discontinuation of ragweed immunotherapy

BACKGROUND

Immunotherapy effectively treats the symptoms of allergic rhinitis and improves its pathophysiology. We studied whether the effects of immunotherapy on the early response to nasal challenge with antigen and seasonal symptoms persist after discontinuation.

METHODS

Twenty subjects with ragweed allergy who were receiving immunotherapy and who had nasal challenges performed before initiation of treatment were selected. The patients had been receiving maintenance therapy with aqueous ragweed extract at a dose of 12 microg of Amb a 1 equivalent for a minimum of 3 years, at which point they were randomized to receive either placebo injections or to continue with the maintenance dose. Nasal challenges were performed before and 1 year after randomization. Nasal challenges were monitored by counting the number of sneezes and measuring histamine, N-alpha-tosyl-L-arginine methyl ester-esterase activity, and kinins in recovered nasal lavages. In the same year symptom diaries were collected during the ragweed season.

RESULTS

The initial immunotherapy significantly reduced responses to nasal challenge in both groups. The group continuing to receive active treatment showed no significant changes from the response before randomization. In contrast, the group randomized to placebo treatment showed a partial return of histamine, kinins, and N-alpha-tosyl-L-arginine methyl ester-esterase in nasal secretions and the numbers of sneezes. IgG antibodies to ragweed declined only in the group switched to placebo treatment. Seasonal rises of IgE antibodies to ragweed did not return during the first season after treatment was stopped. Symptoms reported during the ragweed season were not different between the groups.

CONCLUSIONS

One year after discontinuation of ragweed immunotherapy, nasal challenges showed partial recrudescence of mediator responses even though reports during the season appeared to indicate continued suppression of symptoms.

Low dose clemastine inhibits sneezing and rhinorrhea during the early nasal allergic reaction

BACKGROUND

Clemastine (1 mg) is currently available over-the-counter for the treatment of allergic rhinitis.

OBJECTIVE

To evaluate the efficacy of half the standard dose of clemastine (0.5 mg) in inhibiting the nasal response to allergen and the cutaneous response to histamine.

METHODS

Double-blind, placebo-controlled, crossover study of 20 allergic subjects out of season. The subjects received placebo or clemastine administered one, four, and six hours before the challenges. Filter paper discs were used both to challenge the nasal mucosa with diluent and allergen and collect generated secretions. Sneezes, secretion weights, nasal and ocular symptoms, and albumin levels in nasal secretions were monitored for the nasal challenge. Intradermal skin testing was performed with diluent followed by histamine and the wheal and flare reactions were measured.

RESULTS

There was a significant reduction in the number of sneezes after clemastine administered one, four, and six hours prior to challenge compared with placebo (P < .01). Clemastine administered four and six hours before challenge reduced sneezing significantly more than clemastine administered one hour before challenge (P < .05). Antigen-induced increases in secretion weights and symptoms of rhinorrhea were significantly reduced compared with placebo only when clemastine was administered four and six hours prior to challenge (P < .05). Pretreatment with clemastine had no significant inhibitory effects on other nasal symptoms or on albumin levels in nasal secretions, an objective index of increased vascular permeability. Pretreatment with clemastine did not inhibit the histamine-induced wheal skin reaction but showed a tendency, when administered six hours prior to the intradermal challenge, to reduce the flare reaction induced by the lowest dose of histamine (P = .05).

CONCLUSIONS

The data show that clemastine, given at half the usual dose four and six hours prior to allergen challenge, provides relief for sneezing and rhinorrhea and suggests that this dose might be useful in the treatment of allergic rhinitis.

Ragweed allergic rhinitis and the paranasal sinuses. A computed tomographic study

OBJECTIVE

To explore the potential association of allergic rhinitis and sinusitis.

DESIGN

Prospective clinical trial.

SETTING

Academic tertiary referral center.

PARTICIPANTS

Ten subjects with symptomatic ragweed allergy during the peak of the ragweed season.

MAIN OUTCOME MEASURES

We obtained a paranasal sinus computed tomographic scan on all volunteers and had them complete a modified Rhinitis Quality of Life Questionnaire. All subjects were then treated with intranasal aqueous beclomethasone dipropionate (168 micrograms twice a day) and completed the Rhinitis Quality of Life Questionnaire weekly until the end of the study.

RESULTS

Six of 10 of the subjects had sinus mucosal thickening on computed tomographic scan. All subjects improved symptomatically. A second computed tomographic scan was obtained after the pollen season in 5 patients with mucosal abnormalities, while the patients continued treatment with intranasal steroids and symptomatically improved. The sinus mucosal abnormalities persisted in all patients.

CONCLUSION

Despite the 60% incidence of abnormalities on the computed tomographic scans of the subjects with ragweed allergy during the season, these abnormalities appear, at most, to contribute minimally to the patient's symptoms, since resolution of symptoms was not accompanied by a reduction in sinus mucosal abnormalities.

Bilateral increases in histamine after unilateral nasal allergen challenge

Studying the inflammatory response that follows the early response to nasal challenge with antigen provides a better understanding of allergic rhinitis than just studying the immediate (early) response. Nine allergic volunteers were challenged unilaterally with antigen-containing discs, and bilateral changes in physiologic responses as well as in the concentration of histamine in nasal secretions were measured for 11 h. We found significant immediate increases in symptoms, sneezes, ipsilateral nasal airway resistance, and ipsilateral histamine in the early phase response. Two-thirds of the allergen-challenged volunteers showed increases in physiologic parameters or histamine in the hours after allergen challenge. The pooled data of all subjects exhibited significant increases in bilateral nasal airway resistance and in ipsilateral and contralateral histamine, hours after unilateral provocation. These responses differed significantly from control subjects. In another group of 11 volunteers challenged ipsilaterally with antigen, the number of basophils increased both on the side of challenge and on the contralateral side. The magnitude of the increase on the ipsilateral side correlated with the increase on the contralateral side (r(s) = 0.72). The basophils are the most likely source of the contralateral increase in histamine as they are on the ipsilateral side. Although the mechanisms underlying this contralateral increase in basophils and histamine are not known, we speculate that delayed, neurogenic responses play a contributory role.

Pathophysiology of perennial allergic rhinitis

Allergic rhinitis involves an early phase, largely mediated through mast cells, and a late phase which involves cellular infiltration and mediator release. In the early phase, mast cells release mediators as a result of antigen cross-linking adjacent immunoglobulin E molecules bound to mast cell surfaces. This results in an accumulation of histamine which gives rise to the characteristic symptoms of rhinitis--sneezing, itching, rhinorrhoea and congestion. The late phase of the allergic response (hours after challenge) involves infiltration of the nasal epithelium by eosinophils, basophils, monocytes and T-lymphocytes, which release leukotrienes, kinins, histamine and a host of other mediators. The most important part of the late-phase response is probably mediated via the production of cytokines (IL-4, IL-5, IL-6, IL-8, GM-CSF and RANTES) by mast cells, TH2 lymphocytes or epithelial cells. The infiltration of tissues by cells normally present only in the blood is brought about by the production of adhesion molecules, such as VCAM-1 and E-selectin, which cause circulating eosinophils, basophils and T-lymphocytes to adhere to endothelial cells before moving through the endothelium into the tissue (diapedesis). Neuronal reflexes also play a role in the allergic response, both by mediating local responses to mediators and possibly playing a part in the activation of T-lymphocytes. The allergic response has also been shown to be less intense in a hot, humid environment, and more marked in a cold, dry environment, possibly due to changes in osmolality of the nasal surface fluid. Similar factors may play a role in the aetiology of non-allergic rhinitis.

Treatment with hot, humid air reduces the nasal response to allergen challenge

Ten subjects with asymptomatic seasonal allergy, outside of their allergy season, underwent allergen provocation following 1 hour of exposure to air at either 20 degrees C and 30% relative humidity (RH) or air at 37 degrees C and 90% RH. The ipsilateral changes following antigen challenge were compared under the two conditions. Conditioning of the nose to 37 degrees C, 90% RH reduced total histamine release (7.9 +/- 1.8 ng vs 4.2 +/- 1.3 ng; p < or = 0.05), sneezes (6 +/- 2 vs 3 +/- 1; p < or = 0.05), pruritus (score of 17.4 +/- 6.0 vs score of 2.0 +/- 1.8 out of a total score of 100, p < or = 0.01), nasal airway resistance (1.4 +/- 0.8 kPa/L/sec vs 0.2 +/- 0.1 kPa/L/sec; p < or = 0.05), human serum albumin levels (389.6 +/- 53.4 micrograms vs 242.2 +/- 37.9 micrograms; p < or = 0.05), and congestion (score of 23.8 +/- 4.8 vs score of 10.6 +/- 5.4 out of a total score of 100, p < or = 0.01). It had no effect on the volume of secretions (p = 0.8), lactoferrin levels (p = 0.3), or rhinorrhea (p = 1.0). Thus air at 37 degrees C and 90% RH partially reduces the early response to antigen. Its effects are greatest on histamine release, the vascular response, and neural responses, with no effect on the glandular response. The mechanisms underlying these effects are unknown.

CD4+ lymphocytes are increased in the sinus mucosa of children with chronic sinusitis

OBJECTIVES

To quantitate lymphocyte subtypes in sinus tissues harvested from children with chronic sinusitis and coexisting asthma, allergies, and cystic fibrosis during functional endoscopic sinus surgery and compare them with those in normal adult sphenoid sinus mucosa.

DESIGN

Immunohistochemical staining of surgical specimens with monoclonal antibodies against CD4 and CD8 surface antigens.

SETTING

Tertiary medical center.

PATIENTS

Thirty-two children who underwent functional endoscopic sinus surgery for chronic sinusitis refractory to medical treatment (median age, 8 years; range, 2-13 years) were divided into 3 groups: 10 with asthma, 15 without asthma, and 7 with cystic fibrosis. Sphenoid sinus mucosa obtained from 10 adults (median age, 70 years) undergoing transsphenoidal hypophysectomy was used as control tissue.

MAIN OUTCOME MEASURES

Numbers of CD4+ and CD8+ cells in the lamina propria and epithelium of surgical specimens.

RESULTS

Significantly more CD4+ cells were in the sinus mucosa of patients with chronic sinusitis than in the normal sinus mucosa (P < .01), but there was no significant difference in the number of CD8+ cells (P = 4). Patients with chronic sinusitis with asthma, without asthma, and with cystic fibrosis all had increased numbers of CD4+ cells compared with sphenoid mucosa, with the difference reaching statistical significance only in the subgroup with chronic sinusitis without asthma (P < .001). The numbers of CD4+ cells were higher in patients with chronic sinusitis than in the sphenoid mucosa irrespective of allergic status. Significantly more CD4+ than CD8+ cells were in tissues from the patients with chronic sinusitis irrespective of concomitant diseases or allergic status. CD4+ and CD8+ cells were more numerous in the apical portion of the submucosa (immediately beneath the epithelium) than in the basal portion both in patients with chronic sinusitis and in normal sphenoid tissue.

CONCLUSIONS

Children with chronic sinusitis have predominance of CD4+ cells in the sinus mucosa as compared with normal sphenoid tissue. This contrasts with published results in adults with chromic sinusitis, in whom CD8+ cells predominate in nasal polyps and the submucosa, possibly reflecting a difference in the immunologic response of children and adults.

Unilateral nasal allergen challenge leads to bilateral release of prostaglandin D2

BACKGROUND

Multiple mediators including prostaglandin D2 and leukotriene B4 have been shown to increase in nasal secretions during the early response to nasal challenge with antigen.

OBJECTIVE

Our objective was to investigate the time course of prostanoid and leukotriene B4 release into nasal secretions on both the ipsilateral and contralateral side after a unilateral nasal allergen challenge.

METHODS

We performed a controlled, randomized trial. Six volunteers were challenged unilaterally with antigen or diluent in a randomized order and discs were used to collect nasal secretions from both nostrils at 2 min intervals for 20 min after the challenge. Prostanoids and leukotriene B4 (LTB4) in recovered nasal secretions were measured by combined capillary gas chromatography-negative ion chemical ionization mass spectrometry (GC/MS).

RESULTS

Nasal allergen challenge resulted in a significant and immediate increase in symptoms and sneezing. PGD2 was significantly elevated above diluent values (0.6 +/- 0.6 pg) 30 s after removal of the allergen disc (P < 0.05), reached its peak (423.2 +/- 182.4 pg) at 2 min and then slowly decreased. PGD2 also increased on the contralateral side after unilateral allergen challenge, reaching peak values about six times lower than on the ipsilateral side (70.8 +/- 21.7 pg at 6 min). Levels of 9a, 11b-PGF2 after antigen provocation became significantly higher than after diluent (0 +/- 0 pg) on the ipsilateral side at 2 min (17.2 +/- 5.9 pg), and reached peak levels at 4 min (25.1 +/- 8.0 pg). LTB4 also increased significantly on the side of challenge. For the other prostanoids measured (PGF2, PGF2 alpha, TxB2, 6kPGF1 alpha), no significant changes in either ipsilateral or contralateral secretions were observed after allergen challenge.

CONCLUSIONS

Our study described the kinetics of PGD2 and LTB4 release as well as the contralateral release of PGD2.

Effects of loratadine and terfenadine on the induced nasal allergic reaction

OBJECTIVE

To evaluate the effect of terfenadine and loratadine on the early nasal allergic response to challenge and the subsequent cellular influx and hyperresponsiveness.

DESIGN

Double-blind, placebo-controlled, triple-crossover study.

SUBJECTS

Fourteen, asymptomatic, allergic volunteers.

INTERVENTIONS

After an initial challenge with methacholine chloride, subjects received treatment with placebo, loratadine (10 mg by mouth daily), or terfenadine (60 mg by mouth twice daily) for 1 week, followed by a nasal allergen challenge with lavages; 24 hours later, while the subjects were still receiving medication, the quantity of cells in the nasal lavage was determined, and another challenge with methacholine was done. Mediator levels were quantified in the nasal lavages after the allergen c hallenge, and the weight of the methacholine-induced nasal secretions was measured.

RESULTS

Both loratadine and terfenadine treatment resulted in significant reductions in allergen-induced sneezing and the levels of histamine, kinins, albumin, and N-alpha-tosyl-L-arginine methyl ester-esterase activity in recovered nasal lavages compared with the reductions that resulted from placebo treatment, with no significant difference among the treatments. Treatment had no effect on the levels of tryptase, prostaglandin D2 or leukotriene C4. A significant eosinophil influx into nasal secretions 24 hours after the allergen challenge in patients who were receiving placebo (P=.006) was not affected by loratidine or terfenadine treatment. Comparing methacholine-induced secretions between screening challenges and challenges with the patients who were being treated with either loratadine or terfenadine, there was a significant decrease in secretions after the use of these antihistamines (P<.05).

CONCLUSION

Both loratadine and terfenadine partially inhibit the early nasal response to allergen challenge and the subsequent reactivity to a challenge with methacholine without affecting the influx of eosinophils into nasal secretions.

Duration of action of intranasal atropine on methacholine-induced nasal secretions

OBJECTIVE

To evaluate the duration of the inhibitory action of intranasal atropine on the secretory response to nasal challenge with methacholine.

DESIGN

Double-blind, placebo-controlled, four-way crossover trial.

SUBJECTS

Twelve volunteers with perennial allergic rhinitis.

INTERVENTIONS

Subjects were treated intranasally with placebo or 100, 200, and 400 micrograms of atropine in each nostril. They were then challenged 30 minutes after administration of the nasal spray and hourly for 6 hours with 0.19 mg of methacholine. The weight of nasal secretions generated by methacholine challenge served as an indicator of the secretory response. The nasal challenges and the collection of nasal secretions were performed using filter paper disks.

RESULTS

After placebo treatment, the response to methacholine was similar at each time point. In contrast, all doses of atropine significantly reduced the response to methacholine stimulation at the 30-minute, 1-hour, and 2-hour time points.

CONCLUSIONS

Our data show that the anticholinergic activity of intranasal atropine lasts at least 2 hours with no significant difference in the duration of inhibitory action between the doses used. The results suggest that intranasal atropine could become a therapeutic modality for patients in whom glandular hypersecretion is a major symptom.

Lack of effect of hot, humid air on response to nasal challenge with histamine

We have previously shown that whole body exposure of human subjects to environmental conditions of 37 degrees C and 90% relative humidity (RH) prior to and during nasal challenge with antigen decreases the early response. In this study, we evaluated 1) whether the decreased responses observed resulted from decreased end organ sensitivity to histamine and 2) whether the effect of hot, humid air persisted after the subject exited the hot, humid environment. Ten asymptomatic seasonal allergic subjects and 11 nonallergic subjects were randomized to environmental chamber conditions of either 20 degrees C, 30% RH or 37 degrees C, 90% RH for 1 hour prior to and during performance of a nasal challenge with histamine. Twenty-two hours after exiting the environmental chamber, the allergic subjects were challenged with antigen. During both chamber conditions, histamine challenge was associated with a significant increase in all measured parameters compared to sham challenge, except for the sensations of pruritus and congestion. The response to histamine challenge was not different under the two experimental conditions or between allergic and nonallergic subjects. Following both exposure conditions, allergen challenge was associated with an increase in all measured parameters compared to sham challenge, with no significant difference between the two conditions. Exposure to 37 degrees C, 90% RH minimally affects the response to nasal challenge with histamine, and thus, the previously reported decreases in the early nasal response to antigen may primarily result from reduction in mast cell activation. The effect on antigen does not persist 22 hours after exposure.

Eosinophilia in chronic childhood sinusitis

OBJECTIVES

To quantify eosinophilia in sinus tissues obtained from children with chronic sinusitis and to correlate the degree of eosinophilia with history of asthma, allergy, cystic fibrosis, and preoperative computed tomographic (CT) scans.

DESIGN

Examination of surgical specimens from children who underwent functional endoscopic sinus surgery and controls.

SETTING

Tertiary care medical center.

PATIENTS

Thirty-four children who underwent functional endoscopic sinus surgery for chronic sinusitis refractory to medical treatment were divided into three groups: 13 with asthma, 11 without asthma, and 10 with cystic fibrosis. Normal sphenoid sinus mucosa was also obtained from six adults undergoing transsphenoidal hypophysectomies.

MAIN OUTCOME MEASURES

Number of lamina propria and intraepithelial eosinophils in surgical specimens, allergic status, presence or absence of asthma, and CT scans obtained preoperatively.

RESULTS

There were significantly more lamina propria and intraepithelial eosinophils in the tissue of children with chronic sinusitis compared with normal sphenoid sinus mucosa. More eosinophils were counted in the tissues of patients with asthma and cystic fibrosis compared with patients without concomitant disease, but this did not reach statistical significance. Allergy status did not affect the degree of tissue eosinophilia. Eosinophilia did not correlate with severity of mucosal disease as assessed by CT scans.

CONCLUSIONS

Tissue eosinophilia is a characteristic histologic feature of chronic sinusitis in children, especially those with asthma. The presence of allergy does not predict tissue eosinophilia. Furthermore, the degree of tissue eosinophilia does not correlate with the severity of mucosal thickening seen on CT scans.

Cold dry air-induced rhinitis: effect of inhalation and exhalation through the nose

Ten subjects with a history of cold air-induced nasal symptoms participated in a randomized two-period crossover study to evaluate the occurrence and magnitude of the reaction induced by inhalation and exhalation of cold dry air through the nose. The protocol involved breathing of either warm moist or cold dry air for 45 min at resting breathing rates. The nasal response was quantified by determining the amount of produced secretions as well as by measuring histamine and N-alpha-p-tosyl-L-arginine methyl (TAME) esterase activities in recovered nasal lavage fluids. Symptom scores were obtained. Warm moist air did not increase symptoms nor did it result in any significant changes in secretions or mediator levels. Compared with baseline, cold dry air induced significant rhinorrhea and increased both secretion weights (9.6 +/- 1.3 vs. 28.1 +/- 6.5 mg; P = 0.01) and the levels of histamine (3.9 +/- 1.2 vs. 10.6 +/- 2.7 ng/ml; P = 0.02) and TAME esterase activity (3.1 +/- 0.8 vs. 7.0 +/- 2.0 counts.min-1.10(-3); P = 0.01). We conclude that bidirectional nasal breathing of cold dry air results in a reaction that is qualitatively similar to that induced when air is only inhaled through the nose and exhaled through the mouth.

Inhibition of the response to nasal provocation with bradykinin by HOE-140: efficacy and duration of action

The present studies were undertaken as a first step to evaluate the potential usefulness of the bradykinin antagonist HOE-140 in delineating the role of kinins in the pathogenesis of chronic rhinitis. Intranasal single-dose administration of HOE-140, at doses up to 500 micrograms, was safe and well tolerated. Bradykinin-induced symptoms and increased vascular permeability could be inhibited, in a dose-dependent manner, by preadministration of HOE-140 5 min prior to kinin challenge. The results of dose-ranging experiments suggested that bradykinin and HOE-140 were approximately equipotent at bradykinin receptors. Preadministration of HOE-140 2 h before kinin challenge caused a significant but much weaker level of inhibition than that seen with 5-min preadministration. Comparison of data with those obtained during dose-ranging studies suggested that more than 90% of the administered HOE-140 was lost during this 2-h period. We conclude that topical HOE-140 is an effective inhibitor of the effects of bradykinin on the nasal mucosa but that the short duration of action of this drug may severely limit the utility of HOE-140 in delineating the role of kinins in the pathogenesis of chronic rhinitis.

In vivo human models for the study of anticholinergic drugs

BACKGROUND

The parasympathetic nervous system plays an important role in the nasal response to external stimuli.

OBJECTIVE

To review studies showing the role of the parasympathetic nervous system in the nasal response and the effect of topical, intranasal anticholinergic agents on that response.

METHOD

Literature review of in vivo human studies.

RESULTS

Nasal provocation with methacholine leads to glandular stimulation. The response to methacholine provocation can be blocked by treatment with ipratropium bromide. Stimulation of one nostril with histamine, antigen, and cold, dry air leads to a bilateral secretory response that is partially inhibited by topical treatment with atropine.

CONCLUSION

Topical anticholinergic agents should be useful in the reduction of glandular hypersecretion regardless of the etiology.

The histology of allergic rhinitis and its comparison to cellular changes in nasal lavage

To better understand how changes in cells in nasal secretions reflect changes in the nasal mucosa occurring during allergic reactions, we obtained nasal lavage and biopsy specimens from normal (n = 11) asymptomatic, seasonally allergic (n = 18), and perennially allergic (n = 18) subjects. Initial baseline lavages showed that perennially, and seasonally allergic subjects, out of their allergy seasons, had significantly higher numbers of eosinophils (p < 0.01) and neutrophils (p < 0.01) and total cell counts (p < 0.05) than normal subjects. Biopsy results showed that at baseline, seasonally allergic subjects had thicker mucosa (p < 0.01), greater numbers of intraepithelial mononuclear cells and total cells (p < 0.01), and greater numbers of subepithelial neutrophils (p < 0.001) than perennially allergic subjects. Twenty-four hours after antigen provocation, nasal lavage of allergic subjects showed an increase in the number of eosinophils (p < 0.05). Seasonally allergic subjects also had significant increases in numbers of intraepithelial mononuclear cells (p < 0.05) and total cells (p < 0.01), and in subepithelial eosinophils (p < 0.001) and mononuclear cells (p < 0.05), which were localized to the side challenged. Despite an influx in eosinophils, the epithelial layer was not changed from baseline. The data provide evidence that nasal secretions and the nasal mucosa represent two distinct cellular compartments.