A randomized, double-blind, placebo-controlled trial of anti-IgE for chronic rhinosinusitis

Evidence suggests IgE may play a role in chronic rhinosinusitis (CRS). We sought to determine if treatment with a monoclonal antibody against IgE (omalizumab) is effective in reducing CRS inflammation. We performed a randomized, double blind, placebo controlled clinical trial in subjects with CRS despite treatment (including surgery). Subjects were randomized to receive omalizumab or placebo for 6 months. The primary outcome was quantitative measurement of sinus inflammation on imaging. Secondary outcome measures included quality of life, symptoms, and cellular inflammation, nasal airflow (NPIF) and olfactory testing (UPSIT). Subjects on omalizumab showed reduced inflammation on imaging after treatment, whereas those on placebo showed no change. The net difference, however, was not different between treatments. Treatment with omalizumab was associated with improvement in the Sino-Nasal Outcome Test (SNOT-20) at 3, 5, and 6 months compared to baseline with no significant changes in the control group. Remaining measures showed no significant differences across treatments. We conclude that IgE plays, at most, a small role in the mucosal inflammation of CRS and the symptoms. Placebo controlled, blinded studies with larger enrollment are needed to determine the clinical significance of any potential change.

Desloratadine partially inhibits the augmented bacterial responses in the sinuses of allergic and infected mice

BACKGROUND

Allergic rhinitis (AR) is considered a major predisposing factor for the development of acute bacterial rhinosinusitis. How AR augments a bacterial infection is unknown.

OBJECTIVE

Our purpose in this study was to test whether an H1 receptor antagonist, desloratadine, could reduce the augmented effect of an ongoing allergic reaction on acute bacterial rhinosinusitis.

METHODS

Three groups of infected and ovalbumin (OVA)-sensitized mice were studied: (1) infected and allergic mice treated with desloratadine, (2) infected and allergic mice treated with placebo, and (3) infected mice. A fourth group of uninfected, non-sensitized mice served as a control for the cellular changes. BALB/c mice were sensitized by two intraperitoneal injections of OVA given 8 days apart. One day after the second injection, the mice were nasally exposed daily to 6% OVA (the groups treated with desloratadine or placebo) or phosphate-buffered saline (PBS) (the infection-only group) for 5 days. After the second OVA exposure, the mice were intranasally inoculated with Streptococcus pneumoniae. Desloratadine or placebo was given daily throughout the OVA exposure period. Nasal allergic symptoms were observed by counting of nasal rubbing and sneezing for 10 min after OVA or PBS nasal challenge. On day 5 post-infection, nasal lavage culture was done, and the inflammatory cells in the sinuses were evaluated by flow cytometry.

RESULTS

Mice that were made allergic, infected, and treated with placebo showed more organisms and phagocytes than did only infect mice. They also manifested allergic nasal symptoms and eosinophil influx into the sinuses. Desloratadine treatment during allergen exposure reduced allergic symptoms and reduced sinonasal infection (P<0.05). There tended to be less myeloid cell and neutrophil influx (P=0.09 both), but not eosinophil influx (P=0.85) compared with that in the placebo-treated group.

CONCLUSION

Desloratadine treatment during nasal challenge inhibited allergic symptoms and reduced sinonasal infection, suggesting that histamine via an H1 receptor plays a role in the augmented infection in mice with an ongoing allergic reaction.

Supine position decreases the ability of the nose to warm and humidify air

We tested the hypothesis that decreasing nasal air volume (i.e., increasing nasal turbinate blood volume) improves nasal air conditioning. We performed a randomized, two-way crossover study on the conditioning capacity of the nose in six healthy subjects in the supine and upright position. Cold, dry air (CDA) was delivered to the nose via a nasal mask, and the temperature and humidity of air were measured before it entered and after it exited the nasal cavity. The total water gradient (TWG) across the nose was calculated and represents the nasal conditioning capacity. Nasal volume decreased significantly from baseline without changing the mucosal temperature when subjects were placed in the supine position (P < 0.01). TWG in supine position was significantly lower than that in upright position (P < 0.001). In the supine position, nasal mucosal temperature after CDA exposure was significantly lower than that in upright position (P < 0.01). Our data show that placing subjects in the supine position decreased the ability of the nose to condition CDA compared with the upright position, in contrast to our hypothesis.

Hot, humid air increases cellular influx during the late-phase response to nasal challenge with antigen

BACKGROUND

Inhalation of hot, humid air (HHA: 37 degrees C, > 95% relative humidity (RH)) partially inhibits the early response to nasal challenge with antigen.

OBJECTIVE

To investigate whether HHA inhibited the late-phase response to nasal challenge with antigen and increased hyper-responsiveness of the nasal mucosa to histamine.

METHODS

Twenty subjects with seasonal allergic rhinitis, outside of their allergy season, participated in a randomized, 2-way cross-over study. The subjects continuously breathed room air (25 degrees C, 30% RH) or HHA delivered via a face mask during the entire experiment. Subjects were challenged intranasally with antigen 1 h after beginning conditioning. The response was monitored by symptoms and nasal lavage at 2-h intervals after the last antigen challenge. Eight hours after antigen challenge, nasal challenge with histamine was performed.

RESULTS

Exposure to HHA significantly increased nasal mucosal temperature from baseline without affecting nasal secretion osmolality. HHA significantly inhibited antigen-induced sneezes, congestion, pruritus, and human serum albumin levels during the early response to antigen challenge. HHA exposure, however, was associated with an 8-fold increase in the eosinophil influx and a 15-fold increase in the levels of eosinophil cationic protein during the late-phase response compared to room air. There were no significant differences in nasal hyper-responsiveness to histamine during either exposure.

CONCLUSION

HHA partially decreases the early response to nasal challenge with antigen, but dramatically increases eosinophil influx. Increasing eosinophil number had no effects on the hyper-responsiveness to histamine. We speculate that the physical conditions of air differentially impact the stages of allergic inflammation.

Superiority of an intranasal corticosteroid compared with an oral antihistamine in the as-needed treatment of seasonal allergic rhinitis

BACKGROUND

The daily use of either intranasal corticosteroids or histamine(1) (H(1)) receptor antagonists has proved to be efficacious in the treatment of seasonal allergic rhinitis. Most patients, however, use these medications as needed. Our objective was to compare the effectiveness of as-needed use of H(1) receptor antagonists with that of intranasal corticosteroids in the treatment of seasonal allergic rhinitis.

METHODS

We performed a randomized, open-label, parallel-group study comparing the as-needed use of an H(1) receptor antagonist (loratadine) with that of an intranasal corticosteroid (fluticasone propionate) in the management of fall seasonal allergic rhinitis in the fall of 1999. Subjects kept a diary of their daily symptoms and were examined at enrollment into the study and biweekly for 4 weeks during treatment. Outcome measures were the Rhinoconjunctivitis Quality of Life Questionnaire score, daily symptom diary scores, and the number of eosinophils and the levels of eosinophilic cationic protein in nasal lavage samples.

RESULTS

Patients in the fluticasone-treated group reported significantly better scores in the activity, sleep, practical, nasal, and overall domains (P<.05) of the Rhinoconjunctivitis Quality of Life Questionnaire. The median total symptom score in the fluticasone-treated group was significantly lower than that in the loratadine-treated group (4.0 vs 7.0; P<.01). After treatment, the number of eosinophils was significantly smaller in the fluticasone-treated group compared with the loratadine-treated group (P =.001). Eosinophilic cationic protein levels followed the same pattern, with a significant correlation between the levels of eosinophilic cationic protein and the number of eosinophils (r(s) = 0.70, P<.01).

CONCLUSION

As-needed intranasal corticosteroids reduce allergic inflammation and are more effective than as-needed H(1) receptor antagonists in the treatment of seasonal allergic rhinitis.

The nasal passage of subjects with asthma has a decreased ability to warm and humidify inspired air

We previously showed that individuals with seasonal allergic rhinitis (SAR) had a reduced ability to condition air, which was improved by inflammation. We hypothesized that individuals with perennial allergic rhinitis (PAR) would condition air like SAR with inflammation. Because individuals with asthma usually have inflammation in the nose, we hypothesized that they would condition air like individuals with PAR. We performed a prospective, parallel study on 15 normal subjects, 15 subjects with SAR outside their allergy season, 15 subjects with PAR, and 15 subjects with asthma. Cold, dry air (CDA) was delivered to the nose and the temperature and humidity of the air were measured before entering and after exiting the nasal cavity. The total water gradient (TWG) was calculated and represents the nasal conditioning capacity. The TWG in the SAR group was significantly lower than that in normal subjects. There were no significant differences in TWG between the PAR and normal groups. Subjects with asthma had a significantly lower TWG than did normal subjects. There was a significant negative correlation between TWG and Aas score in the group with asthma (r(s) = -0.8, p = 0.0007). Our data show that subjects with asthma have a reduced ability of the nose to condition CDA compared with normal subjects, but which is similar to SAR out of season.

The otolaryngology research paradox

OBJECTIVE

To determine the attitude toward and the state of research within the field of otolaryngology-head and neck surgery.

DESIGN

A questionnaire was sent to the chairpersons of departments of otolaryngology where residency training is provided.

PARTICIPANTS AND SETTING

Program directors of academic otolaryngology training programs.

MAIN OUTCOME MEASURE

Responses to questionnaire.

RESULTS

Questionnaires were sent to 95 programs from which 86 responses were received. Respondents believed strongly that research was important to the specialty. Only two thirds of the full-time clinical faculty, however, do research, and on average they devote only 17% of their time to this activity. About a third of those doing research have funding, and the National Institutes of Health support only 12% of clinician-investigators. Although program directors believe that clinicians should do research, three fourths stated that clinicians were too busy to accomplish this goal. Surprisingly, half of the respondents were unaware of residency programs that offered 2 years of research training, aimed to develop clinician-investigators, who can become competitive for attainment of research funding.

CONCLUSIONS

Although leaders within our specialty believe that research is important, clinicians are not provided with enough time to conduct research. Furthermore, pathways that would enhance their competitiveness to obtain research funding are not recommended to our future clinicians.

Allergic inflammation enhances bacterial sinusitis in mice

BACKGROUND

Although it is not proven, one factor considered important in the development of sinusitis is allergic rhinitis.

OBJECTIVE

The purpose of this study was to determine whether ongoing allergic rhinitis enhances the infection and inflammation associated with Streptococcus pneumoniae acute sinus infection.

METHODS

BALB/c mice were sensitized to ovalbumin by intraperitoneal injection. After infection of the sinuses by S pneumoniae, either with or without concomitant administration of ovalbumin to induce allergic inflammation, mice were killed at various times and their heads were prepared for histologic evaluation of the sinuses.

RESULTS

Mice became allergic to ovalbumin and developed eosinophilia in the sinus and lung cavities in response to ovalbumin administration to each of the respective cavities. In comparison with controls, the mice with ongoing nasal allergic inflammation that were inoculated with S pneumoniae had significantly more bacteria recovered at sacrifice and had significantly more inflammation, as indicated by neutrophil, eosinophil, and mononuclear influx into the sinus mucosa. The percentage of the sinus area occupied by neutrophil clusters was also increased after infection in the allergic mice in comparison with the control mice.

CONCLUSION

Our data demonstrate that mice can be sensitized to ovalbumin and develop a localized allergic reaction in the skin, nose, or lung. An ongoing local allergic response augments bacterial infection in these animals. We also demonstrate that allergic sensitization alone, allergen exposure alone, or an allergic response at a distal site, the lung, does not augment the sinus infection.

C57Bl/6 and BALB/c mice have similar neutrophil response to acute Streptococcus pneumoniae sinus infections

BACKGROUND

Previous investigations have shown that mice with a tendency toward a T(H)1 or T(H)2 lymphocyte response manifest different reactions to inoculation with the parasite Leishmania major. BALB/c mice (with a tendency for a T(H)2 response) showed evidence of systemic infection, whereas C57Bl/6 mice (with a tendency for a T(H)1 response) showed only a local reaction.

OBJECTIVE

To investigate whether BALB/c and C57Bl/6 mice respond differently to acute bacterial infection of the sinuses.

METHODS

We inoculated the nasal cavities of C57Bl/6 and BALB/c mice with Streptococcus pneumoniae (type ATCC59), or with broth as a control. The mice were humanely killed 2, 5, 10, and 14 days after inoculation. Their heads were fixed, decalcified, and embedded in paraffin blocks. Sections were stained with hematoxylin and eosin, and the degree of inflammation was quantified by the number of neutrophils per square millimeter of the sinus mucosa and the percentage of the sinus cavity occupied by neutrophil clusters.

RESULTS

Both groups of mice showed evidence of inflammation that was significantly greater than controls (P =.01), with no difference between groups. There was a correlation between the number of neutrophils per square millimeter in the sinus mucosa and the percentage of neutrophil clusters (C57Bl/6 mice, r = 0.37, P<.001; BALB/c mice, r = 0.20, P<.001). In the infected mice, the number of infiltrating neutrophils was significantly greater (P<.001) in anatomically lower (dependent) areas of the sinuses compared with the upper areas.

CONCLUSION

Unlike leishmaniasis, acute bacterial sinusitis is not affected by the tendency of the host to favor either a T(H)1 or T(H)2 response.

Antiallergic effects of H1-receptor antagonists

The primary mechanism of antihistamine action in the treatment of allergic diseases is believed to be competitive antagonism of histamine binding to cellular receptors (specifically, the H1-receptors), which are present on nerve endings, smooth muscles, and glandular cells. This notion is supported by the fact that structurally unrelated drugs antagonize the H1-receptor and provide clinical benefit. However, H1-receptor antagonism may not be their sole mechanism of action in treating allergic rhinitis. On the basis of in vitro and animal experiments, drugs classified as H1-receptor antagonists have long been recognized to have additional pharmacological properties. Most first-generation H1-antihistamines have anticholinergic, sedative, local anaesthetic, and anti-5-HT effects, which might favourably affect the symptoms of the allergic response but also contribute to side-effects. These additional properties are not uniformly distributed among drugs classified as H1-receptor antagonists. Azatadine, for example, inhibits in vitro IgE-mediated histamine and leukotriene (LT) release from mast cells and basophils. In human challenge models, terfenadine, azatadine, and loratadine reduce IgE-mediated histamine release. Cetirizine reduces eosinophilic infiltration at the site of antigen challenge in the skin, but not the nose. In a nasal antigen challenge model, cetirizine pretreatment did not affect the levels of histamine and prostaglandin D2 recovered in postchallenge lavages, whereas the levels of albumin, N-tosyl-L-arginine methyl ester (TAME) esterase activity, and LTs were reduced. Terfenadine, cetirizine, and loratadine blocked allergen-induced hyperresponsiveness to methacholine. In view of the complexity of the pathophysiology of allergy, a number of H1 antagonists with additional properties are currently under development for allergic diseases. Mizolastine, a new H1-receptor antagonist, has been shown to have additional actions that should help reduce the allergic response. In animal models, mizolastine inhibits antigen-induced eosinophil infiltration into mouse skin and into the nasal cavity of guinea-pigs. Mizolastine also significantly inhibits antigen-induced neutrophil infiltration into the bronchoalveolar lavage fluids of guinea-pigs. In addition, it inhibits arachidonic acid-induced paw oedema in rats without affecting carrageenin-induced rat paw oedema, suggesting an effect on LT generation. In man, mizolastine inhibits early and late antigen-induced soluble intercellular adhesion molecule 1 (ICAM-1) levels in skin blisters. It also inhibits anaphylactic release of histamine from rodent mast cells, LTC4 and LTB4 release from mouse bone-marrow-derived mast cells, LTC4 release from rat intestinal mast cells, and 5-lipoxygenase activity of polymorphonuclear neutrophils of guinea-pig intestines and rat basophilic leukaemia cells. It is clear that a number of H1-antihistamines have multiple effects on the allergic inflammatory response. It is equally clear that these antiallergic effects are not uniformly shared among all drugs of this class. The assessment of the clinical significance of these results and research regarding the parts of the molecules responsible for these activities are underway.

Absence of nasal mucosal atrophy with fluticasone aqueous nasal spray

OBJECTIVE

To evaluate whether 1 year of continuous treatment with intranasal fluticasone propionate would lead to atrophy in the nasal mucosa compared with an active control, oral terfenadine.

DESIGN

Prospective, randomized, multicenter, open-label, parallel-group study.

SETTING

Two tertiary care academic institutions.

PATIENTS

Seventy-five subjects older than 18 years with perennial allergic rhinitis.

INTERVENTIONS

Patients received either fluticasone propionate aqueous nasal spray, 200 microg once daily, or terfenadine, 60 mg twice daily, for 1 year. Nasal biopsy specimens were obtained before and after 1 year of treatment and were evaluated for evidence of atrophy.

MAIN OUTCOME MEASURES

Epithelial and collagen layer thickness of the nasal mucosa as assessed by light microscopy and the presence and degree of edema, and regularity of collagen fibrils as assessed by electron microscopy. Analyses were performed without knowledge of subject identity or treatment assignment.

RESULTS

Neither fluticasone nor terfenadine treatment led to atrophy in the nasal mucosa by clinical or histologic observation. No significant changes from baseline were observed for any assessment of atrophy. In contrast to what would have been expected if atrophy were to occur, mean epithelial layer thickness in the fluticasone group significantly increased compared with terfenadine treatment (P = .03).

CONCLUSIONS

Treatment with intranasal fluticasone for 1 year increases the thickness of the nasal epithelium as compared with a year's treatment with terfenadine and does not lead to atrophy in the nasal mucosa. The increased thickness in the fluticasone treatment may represent repair from epithelial damage caused by chronic allergic inflammation.

Elevation of nasal mucosal temperature increases the ability of the nose to warm and humidify air

The nose functions to warm and humidify inspired air. The factors that influence these functions have been studied to a limited degree. We have developed a method for measuring the temperature and relative humidity of the air before and after nasal conditioning to study nasal function. In this experiment we studied the effects of raising the mucosal surface temperature by immersion of the feet in warm water. Six subjects (avg. age = 27.0 years) were randomized to immersion of the feet in 30 degrees C and 40 degrees C water. The nasal mucosal temperature increased significantly from the 32.2+/-1.3 degrees C during immersion in the 30 degrees C water to the 33.1+/-1.2 degrees C during immersion in 40 degrees water (p < 0.05). No significant difference in nasal volume was noted between the 30 degrees (17.8+/-4.5 cc) and the 40 degrees (17.7+/-5.3 cc) immersions. There was a significant increase in the conditioning capacity of the nose (as measured by total water content of inspired air) in response to cold-air challenge during the 40 degrees immersion (1669+/-312 mg water) when compared to the 30 degrees immersion (1324+/-152 mg water). From these data we deduce that warming of the nasal mucosa improves the ability of the nose to condition inspired air without a significant change in the volume of the nasal cavity.

Natural and induced allergic responses increase the ability of the nose to warm and humidify air

BACKGROUND

We have previously shown that subjects with seasonal allergic rhinitis out of season had a reduced ability to warm and humidify air compared with normal subjects.

OBJECTIVE

We sought to investigate whether allergic reactions induced by either seasonal exposure or nasal challenge with antigen would decrease the capacity of the nose to condition cold, dry air.

METHODS

We performed two prospective studies comparing the effects of allergic inflammation, induced by either seasonal exposure or nasal challenge with antigen, on nasal conditioning capacity (NCC). The total water gradient (WG) across the nose was used to represent the NCC. In the first study, the NCC was measured and compared before and during the allergy season in 10 subjects with seasonal allergic rhinitis. In the second study, 20 subjects with seasonal allergic rhinitis were recruited outside of the allergy season. NCC was measured and compared before and 24 hours after challenge with antigen.

RESULTS

In the first study, seasonal allergic subjects in season showed a significant increase in NCC when compared with their preseason baseline (total WG in season: 2050 +/- 138 mg vs total WG preseason: 1524 +/- 100 mg; P <.01). In the second study, antigen challenge led to early-phase and late-phase responses. There was a statistically significant increase in NCC 24 hours after antigen challenge compared with that before antigen challenge (total WG after antigen challenge: 1938 +/- 101 mg vs total WG before antigen challenge: 1648 +/- 84 mg; P =.01).

CONCLUSION

Allergic reactions induced by either seasonal exposure or antigen challenge increase the ability of the nose to condition inspired air. We speculate that allergic inflammation increases this ability by changing the perimeter of the nasal cavity.

Ipratropium bromide increases the ability of the nose to warm and humidify air

We have developed a method for measuring the temperature and relative humidity of air prior to and after nasal conditioning and used it to study the effect of treatment with ipratropium bromide on the ability of the nose to condition cold, dry air. We performed randomized, double-blind, placebo-controlled, two-way crossover studies and an open study in nonallergic subjects. The subjects were treated with ipratropium bromide (84 microgram) or normal saline solution sprayed into the nasal cavity 15 min before the measurement of nasal conditioning capacity. Cold, dry air was delivered to the nose via a nasal mask, and the temperature and humidity of air were measured before entering and after exiting the nasal cavity. The total water gradient across the nose was calculated and represents nasal conditioning capacity. Ipratropium bromide treatment significantly increased nasal conditioning capacity when compared with saline. Ipratropium bromide led to less reduction in the cold, dry air-induced decrease in the nasal volume (p < 0.05) without affecting the decrease in nasal surface temperature during cold, dry air exposure (p = 0.3). Our data show that ipratropium bromide increases the ability of the nose to condition cold, dry air. Thus, treating rhinitis with ipratropium bromide should not increase the burden for inspired air conditioning on the conducting pulmonary airways.

Hot, humid air partially inhibits the nasal response to allergen provocation

BACKGROUND

We have previously reported that preconditioning allergic subjects with hot, humid air (HHA) (temperature, 37 degrees C; relative humidity >95%) in an environmental chamber resulted in partial inhibition of the early response to nasal allergen challenge.

OBJECTIVE

To investigate whether this inhibitory effect could be achieved by inhalation of HHA via a face mask.

DESIGN

Randomized, 4-way crossover study.

SUBJECTS

Eighteen subjects with seasonal allergic rhinitis participated in the study outside of their allergy season.

INTERVENTIONS

Subjects underwent preconditioning with room air (RA) (temperature, 25 degrees C; relative humidity <20%) or HHA either in a chamber or delivered via a face mask for 1 hour prior to and during nasal challenge with diluent for the allergen extract followed by 2 increasing doses of allergen.

RESULTS

Net changes from diluent challenge for all parameters were compared between HHA and RA in each delivery method. Hot, humid air delivered by mask significantly inhibited the mean+/-SEM number of allergen-induced sneezes (HHA, 2.7+/-0.6; RA, 6.6+/-2.1; P=.03), congestion score (HHA, 2.3+/-0.5; RA, 3.4+/-0.5; P=.01), and secretion weights (HHA, 26.9+/-4.4 mg; RA, 38.6+/-5.0 mg; P=.048). However, HHA inhaled in a chamber significantly inhibited only the mean+/-SEM allergen-induced congestion (HHA, 1.2+/-0.4; RA, 3.6+/-0.6; P=.002) and pruritus (HHA, 0.7+/-0.3; RA, 2.3+/-0.5; P=.002) scores.

CONCLUSIONS

Preconditioning the nasal mucosa with HHA partially decreases the early response to nasal challenge with antigen irrespective of the administration technique. The secretory response, however, is only inhibited by localized delivery of HHA to the nose. The inhibitory effects of HHA are therefore probably related to local changes in the nasal mucosa and are not dependent on total body exposure to HHA.

Decreased neuropeptide release may play a role in the pathogenesis of nasal polyps

In this in vivo prospective, controlled study, we have examined the capsaicin-induced levels and secretion patterns of the colocalized neuropeptides substance P, calcitonin gene-related peptide (CGRP), and neurokinin A in nasal secretions of subjects with nasal polyps, and we compared these with secretion patterns from healthy subjects and from subjects with allergic rhinitis. Capsaicin was used to elicit neuropeptide release. The neuropeptide levels were measured by an ELISA technique. For substance P, subjects with nasal polyps responded very poorly to capsaicin stimulation. The atopic group was more reactive to capsaicin stimulation than control subjects. For CGRP the increase was immediate in all groups. Atopic subjects and subjects with polyps had a less pronounced but sustained response to capsaicin stimulation. CGRP levels in atopic subjects and those with polyps were restored rapidly. Atopic subjects had higher neurokinin A levels with an immediate and sustained response to capsaicin. Control subjects had higher levels than those with polyps, but both groups were nonresponsive to capsaicin stimulation.

Comparison of the response to histamine challenge of the nose and the maxillary sinus: effect of loratadine

To study the response of the maxillary sinus to histamine provocation, we performed a double-blind, randomized, crossover trial during which nonallergic subjects without symptoms of rhinitis (n = 25) received either 10 mg loratadine or placebo once daily for a week and then underwent nasal challenge with histamine (3, 10, and 30 mg/ml) followed, 24 h later, by a maxillary sinus challenge while still receiving the medication. Nasal challenge with histamine led to significant increases in vascular permeability, reflex nasal secretions, sneezing, and other nasal symptoms. Sinus challenge resulted in significant increases in vascular permeability within the sinus cavity (P < 0.01) and some nasal symptoms but no significant change in reflex nasal secretions. The response of the sinus mucosa to histamine was lower in magnitude than that of the nose. Treatment with loratadine resulted in a significant inhibition of the histamine-induced changes in both nasal and sinus cavities. Our data suggest the lack of a sinonasal reflex response to histamine provocation of the maxillary sinus of nonallergic individuals.

Warming of feet elevates nasal mucosal surface temperature and reduces the early response to nasal challenge with allergen

BACKGROUND

We have previously shown that hot, humid air partially reduces the early allergic response. Mechanisms for this effect have been suggested, but none has gained universal acceptance. The most likely explanations are a modification of mucosal temperature or a reduction in nasal secretion osmolality.

OBJECTIVE

We sought to investigate whether increasing the nasal mucosal surface temperature by immersing feet in warm water (WW) could decrease the immediate nasal response to challenge with allergen.

METHODS

We performed a randomized, 2-way crossover study on 14 subjects with seasonal allergic rhinitis outside of their allergy season. They immersed their feet in either WW (42 degrees C) or room-temperature water (RW; 30 degrees C) for 5 minutes before and during nasal challenge with diluent for the allergen extract, followed by 2 increasing doses of allergen.

RESULTS

There was a statistically significant increase in nasal mucosal temperature from baseline after warming of feet (WW, 1.9 +/- 0.1 degrees C, vs RW, 0.2 +/- 0.1 degrees C; P =. 001), but there were no significant differences in body temperature (WW, 0.1 +/- 0.1 degrees C, vs RW, 0.4 +/- 0.1 degrees C; P =.1). Net changes from diluent challenge for all parameters were compared between immersion of feet in WW and RW. Immersion of feet in WW significantly inhibited allergen-induced sneezes (WW, 5.7 +/- 1.1, vs RW, 11.6 +/- 3.2; P <.01), human serum albumin levels (WW, 941.7 +/- 172.2 microg/mL vs RW, 1524.8 +/- 220.6 microg/mL; P <.01), and secretion weights (WW, 30.5 +/- 7.2 mg, vs RW, 41.8 +/- 6.8 mg; P <. 01).

CONCLUSION

Our data show that warming of feet decreases the early response to nasal challenge with antigen. This inhibitory effect is probably related to the increase in the nasal mucosal temperature.

A technique to measure the ability of the human nose to warm and humidify air

To assess the ability of the nose to warm and humidify inhaled air, we developed a nasopharyngeal probe and measured the temperature and humidity of air exiting the nasal cavity. We delivered cold, dry air (19-1 degrees C, <10% relative humidity) or hot, humid air (37 degrees C, >90% relative humidity) to the nose via a nasal mask at flow rates of 5, 10, and 20 l/min. We used a water gradient across the nose (water content in nasopharynx minus water content of delivered air) to assess nasal function. We studied the characteristics of nasal air conditioning in 22 asymptomatic, seasonally allergic subjects (out of their allergy season) and 11 nonallergic normal subjects. Inhalation of hot, humid air at increasingly higher flow rates had little effect on both the relative humidity and the temperature of air in the nasopharynx. In both groups, increasing the flow of cold, dry air lowered both the temperature and the water content of the inspired air measured in the nasopharynx, although the relative humidity remained at 100%. Water gradient values obtained during cold dry air challenges on separate days showed reproducibility in both allergic and nonallergic subjects. After exposure to cold, dry air, the water gradient was significantly lower in allergic than in nonallergic subjects (1,430 +/- 45 vs. 1,718 +/- 141 mg; P = 0.02), suggesting an impairment in their ability to warm and humidify inhaled air.

Relationship between histamine and physiological changes during the early response to nasal antigen provocation

To investigate the temporal relationships of mediator release and physiological changes during the early response to allergen, we challenged allergic individuals intranasally with antigen and followed their responses. This was done by using small filter paper disks to challenge one nostril and collect secretions from both the challenged and the contralateral nostril, thus enabling us to evaluate the nasonasal reflex. There was a significant increase in sneezing after allergen challenge that peaked within 2 min and returned to baseline. The weights of nasal secretions as well as nasal symptoms increased immediately and remained significantly elevated for 20 min in both nostrils. Nasal airway resistance increased slowly, reaching its peak at approximately 6 min after challenge on the ipsilateral side, but it did not change on the contralateral side. Histamine levels peaked 30 s after removal of the allergen disk on the side of challenge, whereas albumin levels peaked after those of histamine. Lactoferrin paralleled the increase in secretion weights and occurred in both nostrils. Increasing doses of antigen produced dose-dependent increases in all parameters, whereas control challenges produced no response. These studies describe a human model for the evaluation of the allergic response that is capable of simultaneously measuring mediator release and the physiological response, including the nasonasal reflex. This model should prove useful in studying the mechanism of allergic rhinitis in humans.

Optimizing treatment options

Full and accurate diagnosis of allergic rhinitis is important as a basis for treatment decisions, as many nasal disorders have similar signs and symptoms. Optimal allergen avoidance is the starting point of treatment, so causative allergens need to be identified. Oral antihistamines are effective in relieving the majority of symptoms of allergic rhinitis and allergic conjunctivitis, but provide only partial relief from nasal congestion. Topical alpha-adrenergic decongestants help to relieve congestion, but prolonged use leads to rhinitis medicamentosa. Systemic decongestants are less effective than topical agents and their use is limited by systemic and central side-effects. The value of leukotriene antagonists has yet to be fully evaluated. Intranasal ipratropium bromide helps to control watery secretions, and an aerosol may be more effective than an aqueous solution. Topical glucocorticosteroids, such as triamcinolone, are the most potent and effective agents available for treating allergic rhinitis. The available evidence indicates that there is very little systemic absorption. Sodium cromoglycate is effective in allergic rhinitis, though less so than topical steroids, and has the least adverse effects among the antiallergic agents. Immunotherapy can be effective and may be indicated in individuals who cannot avoid the causative allergen. Special considerations apply to the treatment of allergic rhinitis in elderly or pregnant patients. Finally, patients with long-standing allergic conditions should be re-assessed regularly.

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.