Large-scale provocation studies identify maladaptive responses to ubiquitous aeroallergens as a correlate of severe allergic rhinoconjunctivitis and asthma

BACKGROUND

Allergic asthma (AA) and allergic rhinoconjunctivitis (ARC) are common comorbid environmentally triggered diseases. We hypothesized that severe AA/ARC reflects a maladaptive or unrestrained response to ubiquitous aeroallergens.

METHODS

We performed provocation studies wherein six separate cohorts of persons (total n = 217) with ARC, with or without AA, were challenged once or more with fixed concentrations of seasonal or perennial aeroallergens in an aeroallergen challenge chamber (ACC).

RESULTS

Aeroallergen challenges elicited fully or partially restrained vs. unrestrained evoked symptom responsiveness, corresponding to the resilient and adaptive vs. maladaptive AA/ARC phenotypes, respectively. The maladaptive phenotype was evoked more commonly during challenge with a non-endemic versus endemic seasonal aeroallergen. In an AA cohort, symptom responses evoked after house dust mite (HDM) challenges vs. recorded in the natural environment were more accurate and precise predictors of asthma severity and control, lung function (FEV1), and mechanistic correlates of maladaptation. Correlates included elevated levels of peripheral blood CD4+ and CD8+ T-cells, eosinophils, and T-cell activation, as well as gene expression proxies for ineffectual epithelial injury/repair responses. Evoked symptom severity after HDM challenge appeared to be more closely related to levels of CD4+ and CD8+ T-cells than eosinophils, neutrophils, or HDM-specific IgE.

CONCLUSIONS

Provocation studies support the concept that resilience, adaptation, and maladaptation to environmental disease triggers calibrate AA/ARC severity. Despite the ubiquity of aeroallergens, in response to these disease triggers in controlled settings (ie, ACC), most atopic persons manifest the resilient or adaptive phenotype. Thus, ARC/AA disease progression may reflect the failure to preserve the resilient or adaptive phenotype. The triangulation of CD8+ T-cell activation, airway epithelial injury/repair processes and maladaptation in mediating AA disease severity needs more investigation.

Birch-naive, oak-allergic subjects' response to birch pollen in an environmental chamber

Background: Oak and birch pollens are strongly cross-reactive. It is unknown how robust this cross-reactivity is in patients without natural exposure to pollen of both trees. We assessed the symptom response to birch pollen in subjects with skin-prick test (SPT) results positive to oak and birch but only naturally exposed to oak by using an allergen challenge chamber. Methods: The subjects with SPT results positive to oak and birch had their serum-specific immunoglobulin E (ssIgE) to oak and birch antigens measured. Residential historical data were obtained. The subjects were exposed to birch pollen (3500 ± 700 grains/m³) in two consecutive 3-hour challenges. Symptoms were recorded at baseline and 30-minute intervals. Results: Twenty-four subjects, 12 men; ages 20-58 years, completed the study. Sixteen subjects (66.7%) responded with high Total Symptom Scores (TSS) ≥10 of a maximum 21. Twelve subjects (50%) had ssIgE values ≥0.70 kU/L to oak, 10 of whom had ssIgE values ≥0.70 kU/L to birch. These 10 subjects had a significantly higher maximum TSS than the rest. Also, 15 subjects without a previous natural exposure to birch pollen responded with TSS equivalent to the 9 subjects with previous exposure. Conclusion: Virginia live oak ssIgE levels of patients allergic to oak and birch correlated with the symptom response to birch pollen exposure, even without previous natural exposure to birch. The subjects naive to birch pollen responded to birch pollen exposure with symptoms comparable with both those with previous sustained exposure and also those who resided in endemic areas, as reported by other researchers.

Technical standards in allergen exposure chambers worldwide - an EAACI Task Force Report

Allergen exposure chambers (AECs) can be used for controlled exposure to allergenic and non-allergenic airborne particles in an enclosed environment, in order to (i) characterize the pathological features of respiratory diseases and (ii) contribute to and accelerate the clinical development of pharmacological treatments and allergen immunotherapy for allergic disease of the respiratory tract (such as allergic rhinitis, allergic rhinoconjunctivitis, and allergic asthma). In the guidelines of the European Medicines Agency for the clinical development of products for allergen immunotherapy (AIT), the role of AECs in determining primary endpoints in dose-finding Phase II trials is emphasized. Although methodologically insulated from the variability of natural pollen exposure, chamber models remain confined to supporting secondary, rather than primary, endpoints in Phase III registration trials. The need for further validation in comparison with field exposure is clearly mandated. On this basis, the European Academy of Allergy and Clinical Immunology (EAACI) initiated a Task Force in 2015 charged to gain a better understanding of how AECs can generate knowledge about respiratory allergies and can contribute to the clinical development of treatments. Researchers working with AECs worldwide were asked to provide technical information in eight sections: (i) dimensions and structure of the AEC, (ii) AEC staff, (iii) airflow, air processing, and operating conditions, (iv) particle dispersal, (v) pollen/particle counting, (vi) safety and non-contamination measures, (vii) procedures for symptom assessments, (viii) tested allergens/substances and validation procedures. On this basis, a minimal set of technical requirements for AECs applied to the field of allergology is proposed.

Olopatadine-mometasone combination nasal spray: Evaluation of efficacy and safety in patients with seasonal allergic rhinitis

Background: GSP301 is an investigational fixed-dose combination nasal spray that contains the antihistamine, olopatadine hydrochloride (HCl), and the corticosteroid, mometasone furoate. Objective: To evaluate the efficacy and safety of GSP301 in patients with seasonal allergic rhinitis (SAR). Methods: In this double-blind, randomized, parallel-group study, patients (≥12 years of age) with SAR were equally randomized to intranasal GSP301 (olopatadine 665 μg and mometasone 25 μg), olopatadine HCl (665 μg), mometasone furoate (25 μg), or placebo for 14 days of twice-daily treatment. The primary end point was the mean change from baseline in the average A.M. and P.M. 12-hour reflective Total Nasal Symptom Score (rTNSS) analyzed by using mixed-effect model repeated measures (p < 0.05 indicates statistical significance). Additional assessments included instantaneous TNSS (iTNSS), individual nasal symptoms, reflective Total Ocular Symptom Score (rTOSS) and instantaneous Total Ocular Symptom Score (iTOSS), onset of action, Physician-assessed Nasal Symptom Score (PNSS), quality of life, and adverse events (AE). Results: A total of 1180 patients were randomized. Over 14 days of treatment, GSP301 significantly improved average A.M. and P.M. rTNSS versus placebo (least squares mean difference -0.98 [95% confidence interval, -1.38 to -0.57]; p < 0.001) and versus olopatadine (p = 0.003), and approached statistical significance versus mometasone (p = 0.059). GSP301 also significantly improved average A.M. and P.M. iTNSS versus placebo and both monotherapies (p < 0.05, all). Further, GSP301 significantly improved individual nasal symptoms, overall ocular symptoms (rTOSS and iTOSS), and overall quality of life versus placebo (p < 0.01, all). Onset of action for GSP301 was observed within 15 minutes and was maintained at all subsequent time points assessed. Results for the PNSS also were significant for GSP301 versus placebo (p < 0.001). The percentages of patients with treatment-emergent AEs treated with GSP301, olopatadine, mometasone, and placebo were 12.9, 12.5, 7.1, and 9.4%, respectively. Conclusion: GSP301 was efficacious and well tolerated for the treatment of SAR symptoms compared with placebo, with a rapid onset of action of 15 minutes in patients ≥12 years of age.Clinical trial NCT02631551, <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.clinicaltrials.gov">www.clinicaltrials.gov</ext-link>.

Clinical standardization of two controlled allergen challenge facilities: The Environmental Exposure Unit and the Biogenics Research Chamber

BACKGROUND

Controlled allergen challenge facilities (CACF), in disparate geographic regions with dissimilar engineering and base populations, have historically functioned as single, independent sites in clinical allergy trials. We aimed to demonstrate "between-unit reproducibility" to allow controlled challenge trials of participants using 2 CACFs.

OBJECTIVE

To compare and standardize 2 CACFs located in Kingston, Ontario, Canada, and San Antonio, Texas, by examining participant-reported symptom severity during qualifying and treatment visits and evaluating response to treatment, while using the same allergen.

METHODS

At 2 different CACFs, participants were enrolled in a double-blind, placebo-controlled, crossover intervention trial with cetirizine 10 mg. Different distribution devices delivered common short ragweed pollen via laminar air flow and maintained an airborne concentration of 3500 ± 700 grains/m³ in both facilities. A 1-hour "sham" run with no pollen release preceded a priming exposure of 3 hours and was followed 3 days later by a qualifying/treatment 5-hour exposure. At least 14 days later, another priming exposure was followed by the crossover exposure and treatment.

RESULTS

Forty-eight and 43 subjects completed the study at Kingston and San Antonio, respectively. Demographics were similar. Fewer than 10% exhibited symptoms with sham exposure. No significant differences were found between the 2 facilities in maximal total rhinoconjunctivitis symptom score, total nasal symptom score, and total ocular symptom score, nor in areas under the curve. In both facilities, no significant effects of cetirizine 10 mg over placebo were detected.

CONCLUSION

The results were equivalent, demonstrating that the 2 CACFs can be used together in dual-center clinical trials and show the possibility of multicenter trials involving multiple CACFs.

Redness response phenotypes of allergic conjunctivitis in an allergen challenge chamber

BACKGROUND

There are few direct data concerning symptom dynamics of allergic conjunctivitis (AC) in an allergen challenge chamber (ACC).

OBJECTIVE

To determine the AC dynamics on subsequent exposures to ragweed pollen (RW) in individuals with allergic rhinitis in an ACC. To determine whether consecutive exposures in an ACC have any persistent detrimental ocular physical effects.

METHODS

Participants underwent 3 exposures to RW in an ACC. Ocular symptoms of itching and tearing were self-assessed. Ocular redness and lid swelling were assessed by trained ophthalmic technicians. Complete ophthalmic examinations (COEs) were performed by an ophthalmologist.

RESULTS

A total of 188 of 201 participants (93%) developed an ocular redness score of 2 or more in each eye in ACC exposure 1. Reproducibility of redness occurred in approximately 70% of individuals completing ACC exposures 1 through 3. There were no significant changes between baseline COE and end of study COE. Phenotypes were identified by redness responses during and after exposure. Baseline total ocular symptom scores, at 24 hours after a priming exposure, were identified as late-phase reactions rather than enhanced sensitivity.

CONCLUSION

When assessed by trained professionals, AC was present with a very high frequency in selected individuals allergic to RW monitored in an ACC. Intrasubject reproducibility of redness was consistent across 3 ACC allergen exposures. Phenotypes were identified as early-phase responses, protracted early-phase responses, dual responses, and late-phase responses.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02079649.

The dietary form of choline during lactation affects maternal immune function in rats

PURPOSE

The present study was designed to determine the effects of both choline form and availability on maternal immune function during lactation.

METHODS

Sprague-Dawley rats were randomized to one of the three diets 24-48 h before parturition and fed ad libitum until 21 days postnatal: 1 g/kg choline as free choline (C, n = 11), the current form, and amount of choline in commercial diets; 1 g/kg choline as phosphatidylcholine (PC1, n = 11); or 2.5 g/kg choline as PC (PC2.5, n = 8). Choline metabolites in offspring stomach contents were quantified. At 21 days, lymphocytes from mothers' mesenteric lymph nodes and spleens were isolated and phenotypes and ex vivo cytokine production after mitogen exposure were determined.

RESULTS

There was a higher proportion of choline and a lower proportion of lyso-PC in stomach contents (representing dam's milk) of C pups compared to PC1. In the mesenteric lymph nodes, feeding PC1 compared to C led to a higher IL-2 production after Concanavalin A (ConA) stimulation and a higher proportion of T cells (CD3+) and a lower proportion of B cells [immunoglobulin (Ig)κ, CD45RA+, and IgM+; P < 0.05]. Splenocytes from the PC1 group produced more IL-6 and TNF-α after lipopolysaccharides stimulation compared to C (P < 0.05). Splenocytes from the PC2.5 group produced more IL-2 and IL-6 after ConA stimulation compared to PC1 (P < 0.05).

CONCLUSIONS

Feeding choline as PC in the maternal diet improved the ability of immune cells to respond ex vivo to mitogens and increasing the amount of PC in the diet further improved T cell proliferation.

Preservation of epithelial cell barrier function and muted inflammation in resistance to allergic rhinoconjunctivitis from house dust mite challenge

BACKGROUND

An emerging paradigm holds that resistance to the development of allergic diseases, including allergic rhinoconjunctivitis, relates to an intact epithelial/epidermal barrier during early childhood. Conceivably, the immunologic and genomic footprint of this resistance is preserved in nonatopic, nonallergic adults and is unmasked during exposure to an aeroallergen.

OBJECTIVE

The aim of this study was to obtain direct support of the epithelial/epidermal barrier model for allergic rhinoconjunctivitis.

METHODS

Twenty-three adults allergic to house dust mites (HDMs) (M+) and 15 nonsensitive, nonallergic (M-) participants completed 3-hour exposures to aerosolized HDM (Dermatophagoides pteronyssinus) powder on 4 consecutive days in an allergen challenge chamber. We analyzed: (1) peripheral blood leukocyte levels and immune responses; and (2) RNA sequencing-derived expression profiles of nasal cells, before and after HDM exposure.

RESULTS

On HDM challenge: (1) only M+ persons developed allergic rhinoconjunctivitis symptoms; and (2) peripheral blood leukocyte levels/responses and gene expression patterns in nasal cells were largely concordant between M+ and M- participants; gross differences in these parameters were not observed at baseline (pre-exposure). Two key differences were observed. First, peripheral blood CD4⁺ and CD8⁺ T-cell activation levels initially decreased in M- participants versus increased in M+ participants. Second, in M- compared with M+ participants, genes that promoted epidermal/epithelial barrier function (eg, filament-aggregating protein [filaggrin]) versus inflammation (eg, chemokines) and innate immunity (interferon) were upregulated versus muted, respectively.

CONCLUSION

An imprint of resistance to HDM challenge in nonatopic, nonallergic adults was muted T-cell activation in the peripheral blood and inflammatory response in the nasal compartment, coupled with upregulation of genes that promote epidermal/epithelial cell barrier function.

Efficacy and safety of beclomethasone dipropionate nasal aerosol in children with perennial allergic rhinitis

BACKGROUND

Beclomethasone dipropionate (BDP) nasal aerosol (non-aqueous) is approved for management of seasonal and perennial allergic rhinitis (PAR) in adolescents and adults.

OBJECTIVE

To evaluate the efficacy and safety of BDP nasal aerosol at 80 μg/day in children with PAR.

METHODS

This 12-week, phase 3, double-blinded, placebo-controlled, parallel-group study randomized 547 children (4-11 years old) with PAR to once-daily BDP nasal aerosol at 80 μg/day or placebo. The primary end point was change from baseline in average morning and evening reflective total nasal symptom score (rTNSS) during the first 6 weeks of treatment in patients 6 to 11 years old. Changes from baseline in average morning and evening instantaneous TNSS (iTNSS) in children 6 to 11 years old and average rTNSS and iTNSS in children 4 to 11 years old were assessed during the first 6 weeks of treatment.

RESULTS

Improvements were significantly greater with BDP nasal aerosol than with placebo during the first 6 weeks of treatment in children 6 to 11 years old in average morning and evening rTNSS and iTNSS (mean treatment difference -0.66 [P = .002] and -0.58 [P = .004], respectively). Improvements in average morning and evening rTNSS and iTNSS also were significantly greater in patients 4 to 11 years receiving BDP nasal aerosol than with placebo during the first 6 weeks of treatment (P = .002 and P = .004, respectively). Similar improvements were seen during 12 weeks of treatment. The safety profile of BDP nasal aerosol was comparable to that of placebo.

CONCLUSION

The BDP nasal aerosol at 80 μg/day in children 4 to 11 years old was well tolerated and effective in controlling nasal symptoms of PAR.

TRIAL REGISTRATION

www.clinicaltrials.gov, identifier NCT01783548.

Cockroach sensitization mitigates allergic rhinoconjunctivitis symptom severity in patients allergic to house dust mites and pollen

BACKGROUND

Modifiers of symptom severity in patients with allergic rhinoconjunctivitis (AR) are imprecisely characterized. The hygiene hypothesis implicates childhood microbial exposure as a protective factor. Cockroach sensitization (C+) might be a proxy for microbial exposure.

OBJECTIVE

We sought to determine whether C+ assayed by means of skin prick tests influenced AR symptom severity in controlled and natural settings.

METHODS

Total symptom scores (TSSs) were recorded by 21 participants with house dust mite allergy (M+) in the natural setting and during repeated exposures of 3 hours per day to house dust mite allergen in an allergen challenge chamber (ACC). In M+ participants the peripheral blood and nasal cells were assayed for T-cell activation and transcriptomic profiles (by using RNA sequencing), respectively. Participants allergic to mountain cedar (n = 21), oak (n = 34), and ragweed (n = 23) recorded TSSs during separate out-of-season exposures to these pollens (any pollen sensitization [P+]) in the ACC; a subset recorded TSSs in the pollination seasons.

RESULTS

The hierarchy of TSSs (highest to lowest) among M+ participants tracked the following skin prick test sensitization statuses: M+P+C- > M+P+C+ > M+P-C- > M+P-C+. In nasal cells and peripheral blood the immune/inflammatory responses were rapidly resolved in M+P+C+ compared with M+P+C- participants. Among those allergic to pollen, C+ was associated with a lower TSS during pollen challenges and the pollination season. After aggregated analysis of all 4 ACC studies, C+ status was associated with a 2.8-fold greater likelihood of a lower TSS compared with C- status (odds ratio, 2.78; 95% CI, 1.18-6.67; P = .02).

CONCLUSIONS

C+ status is associated with mitigation of AR symptom severity in adults with AR.

The mountain cedar model in clinical trials of seasonal allergic rhinoconjunctivitis

BACKGROUND

Clinical trials of seasonal allergic rhinoconjunctivitis use the mountain cedar (Juniperus ashei) season as the predominate model.

OBJECTIVE

To evaluate clinical trials of rhinoconjunctivitis using mountain cedar, to present analysis of pollen counts during 18 seasons, and to discuss the model.

METHODS

The medical literature was searched for clinical trials performed using mountain cedar either in or out of season. Pollen counts were recorded and analyzed for the duration of 18 seasons.

RESULTS

Thirty-eight trials were identified. Of these, 1 evaluated onset of allergy, 8 were immunotherapy trials, 28 were pharmaceutical clinical trials, and 1 studied symptoms elicited in a pollen challenge chamber trial. Many generic equivalency trials are unreported. In the 18 years of counts in the Texas Hill Country, a dependable and intense pollen density was present in every season. The combination of dependable seasons without confounding pollens, the large number of allergic patients, and the ability to concentrate resources in one geographic area has made mountain cedar allergy a mainstay for therapeutic trials for allergic rhinoconjunctivitis.

CONCLUSION

Mountain cedar allergy presents a dependable and durable model of allergic rhinoconjunctivitis.

Responses to ragweed pollen in a pollen challenge chamber versus seasonal exposure identify allergic rhinoconjunctivitis endotypes

BACKGROUND

The level of concordance between allergic symptoms induced on exposure to pollen in a pollen challenge chamber (PCC) versus the natural season is unknown.

OBJECTIVE

We sought to test the hypothesis that the symptom levels of allergic rhinoconjunctivitis elicited after out-of-season exposure to short ragweed in a PCC and during the natural season for giant ragweed pollen are highly correlated.

METHODS

Thirty-one ragweed-sensitive participants recorded symptoms for 15 days during the natural giant ragweed season in San Antonio, Texas. Twenty-six of these participants were challenged to short ragweed pollen in a PCC for 3 hours per day for up to 4 days.

RESULTS

In the PCC participants were dichotomized into those in whom low versus high levels of symptoms developed slowly or rapidly (ie, slow/low vs rapid/high). Each successive exposure visit associated with a progressive increase in symptom levels that approximated those experienced during the natural season. Hierarchic clustering identified 3 endotypes: endotypes I and II reflected concordantly low (n= 7) versus high (n = 14) total symptom scores (TSSs) in both the natural season and the PCC, respectively. Accordingly, the correlation between the TSSs recorded in the natural season and in the PCC for these 21 participants was very high. Although participants with endotype III (n = 5) had greater TSSs in the natural season than in the PCC, the degree of correlation between the TSSs remained high.

CONCLUSIONS

Our findings affirm our hypothesis, underscore the high cross-reactivity between distinct pollens, and highlight the utility of the PCC to identify novel allergy endotypes that might have contrasting mechanistic underpinnings and potentially therapeutic responses.

Safety and efficacy of once-daily treatment with beclomethasone dipropionate nasal aerosol in subjects with perennial allergic rhinitis

Intranasal corticosteroids are recommended as first-line therapy for the treatment of the symptoms of persistent allergic rhinitis (AR). Since the phase-out of chlorofluorocarbon nasal aerosols, intranasal corticosteroids have been available only as aqueous nasal sprays. This study was designed to assess the efficacy, safety, and quality-of-life benefits of beclomethasone dipropionate (BDP) hydrofluoroalkane nasal aerosol in subjects with perennial AR (PAR). After a 7- to 21-day placebo run-in period, eligible subjects aged ≥12 years with PAR were randomized to 6 weeks of once-daily treatment with BDP nasal aerosol at 320 μg or placebo. Reflective and instantaneous total nasal symptom scores (rTNSS and iTNSS, respectively), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score, and physician-assessed total nasal symptom score were evaluated. The primary end point was change from baseline in average morning (A.M.) and evening (P.M.) subject-reported rTNSS over the 6-week treatment period. Safety and tolerability were also assessed. Treatment with BDP nasal aerosol showed significantly greater improvement in average A.M. and P.M. rTNSS compared with placebo (mean treatment difference, -0.84; 95% confidence interval, -1.2, -0.5; p < 0.001). Greater improvements in rTNSS were reported as early as day 1 and were maintained throughout the 6-week treatment period with the exception of day 2. Greater improvements were seen for all four individual nasal symptoms (nasal congestion, nasal itching, rhinorrhea, and sneezing) with BDP nasal aerosol compared with placebo. Similarly, significant improvements were seen in average A.M. and P.M. iTNSS (p < 0.001) and RQLQ score (p = 0.001) with BDP nasal aerosol compared with placebo. In addition, BDP nasal aerosol treatment was well tolerated, and its safety profile was comparable to that of placebo. This clinical study indicated that treatment with BDP nasal aerosol provides statistically significant and clinically meaningful nasal symptom relief accompanied by improved quality of life in subjects with PAR. Additionally, treatment with BDP nasal aerosol was well tolerated with a safety profile comparable to that of placebo. This study was part of the clinical trial NCT01134705 registered in www.ClinicalTrials.gov.

Ciclesonide for the treatment of seasonal allergic rhinitis

Allergic rhinitis is considered one of the most common afflictions of humans, affecting up to 30% of the world's population, and is increasing in incidence. Primary symptoms, comorbid conditions and complications of this disorder exact a significant toll, resulting in an enormous physical, social and economic impact on society. Single-season allergic rhinitis accounts for approximately 20% of cases of allergic rhinitis with another 40% having mixed seasonal-perennial presentations. Management of this disorder encompasses several treatment options, with intranasal corticosteroids recommended as first-line treatment in moderate-to-severe seasonal allergic rhinitis in current practice parameters. Ciclesonide is the most recently approved product in this category for the management of seasonal allergic rhinitis and is the subject of this article.

Fluticasone furoate nasal spray is more effective than fexofenadine for nighttime symptoms of seasonal allergy

Nasal symptoms of allergic rhinitis are an important cause of sleep disturbance. Reduction of nasal symptoms, particularly nasal obstruction, has been linked to improvements in self-reported sleep quality. The enhanced-affinity intranasal corticosteroid fluticasone furoate and the oral antihistamine fexofenadine were compared with respect to nighttime symptoms of seasonal allergic rhinitis. In two randomized, double-blind, double-dummy, parallel-group studies, patients received fluticasone furoate nasal spray (FFNS),110 microg (study 1, n = 312; study 2, n = 224); fexofenadine, 180 mg (study 1, n = 311; study 2, n = 227); or placebo (study 1, n = 313; study 2, n = 229) once daily for 2 weeks. Fluticasone furoate was more effective (p < 0.001) than fexofenadine and placebo in both studies with respect to the mean changes from baseline over the treatment period in the nighttime symptoms score, nighttime reflective total nasal symptom score, predose instantaneous nasal symptom score, and morning peak nasal inspiratory flow. Fluticasone furoate was more effective than placebo (p <or= 0.001) in study 1 and more effective than both placebo and fexofenadine (p <or= 0.034) in study 2 with respect to the mean changes from baseline in the nighttime reflective total ocular symptom score and predose instantaneous total ocular symptom score. In these double-dummy studies, fexofenadine did not separate from placebo in comparisons of the nighttime symptoms score or the nighttime nasal or ocular symptom measures. The incidence of adverse events was similar among groups. FFNS once daily was more effective than fexofenadine and placebo with respect to nighttime sleep disturbance caused by seasonal allergy symptoms.

Hypersensitivity pneumonitis: beyond classic occupational disease-changing concepts of diagnosis and management

OBJECTIVE

To review inhaled antigens in home environments that cause hypersensitivity pneumonitis (HP) of varied clinical expressions and histopathologic patterns.

DATA SOURCES

Computer-assisted MEDLINE and manual searches for articles concerning HP, interstitial lung disease (ILD), epidemiology of HP and ILD, challenge procedures of HP, and indoor fungi.

STUDY SELECTION

Published articles concerning inhaled antigens in home environments and HP were selected.

RESULTS

Current criteria for the diagnosis of HP are too restrictive, because most apply only to the classic acute presentation and are of limited value in the subacute and insidious forms. Clinical expressions vary across the gamut of respiratory tract signs and symptoms. Patterns on lung biopsy may include all histopathologic descriptions of idiopathic ILD. The home is the likely causative environment rather than the workplace. Exposures may be occult and require in-depth environmental histories and on-site investigations to detect antigens and sources.

CONCLUSIONS

Natural or environmental challenges have become an important tool for diagnosing HP and determining effectiveness of remediation. Early diagnosis and effective remediation of the cause lead to a high survival rate, whereas diagnosis in advanced stages leads to disability and/or premature death.

Toxic mold: phantom risk vs science

OBJECTIVE

To review the available literature on the subject of fungi (molds) and their potential impact on health and to segregate information that has scientific validity from information that is yet unproved and controversial.

DATA SOURCES

This review represents a synthesis of the available literature in this area with the authors' collective experience with many patients presenting with complaints of mold-related illness.

STUDY SELECTION

Pertinent scientific investigation on toxic mold issues and previously published reviews on this and related subjects that met the educational objectives were critically reviewed.

RESULTS

Indoor mold growth is variable, and its discovery in a building does not necessarily mean occupants have been exposed. Human response to fungal antigens may induce IgE or IgG antibodies that connote prior exposure but not necessarily a symptomatic state. Mold-related disease has been discussed in the framework of noncontroversial and controversial disorders.

CONCLUSIONS

When mold-related symptoms occur, they are likely the result of transient irritation, allergy, or infection. Building-related illness due to mycotoxicosis has never been proved in the medical literature. Prompt remediation of water-damaged material and infrastructure repair should be the primary response to fungal contamination in buildings.

Hypersensitivity pneumonia-nonspecific interstitial pneumonia/fibrosis histopathologic presentation: a study in diagnosis and long-term management

BACKGROUND

Nonspecific interstitial pneumonia/fibrosis (NSIP) has been classified a form of idiopathic interstitial pneumonia/fibrosis. We have shown that cases of NSIP without demonstrable serum precipitins may be caused by inhalation of high levels of mold and/or bacteria in closed environments.

OBJECTIVE

We report a patient with a clinical and histopathologic diagnosis of NSIP without serum precipitins caused by a microbial contamination in her home. Her case was converted from an acute to an insidious clinical presentation by inadequate remediation. A prolonged avoidance-challenge technique demonstrated that this case of NSIP was a form of hypersensitivity pneumonia that was reversible by effective remediation.

METHODS

The patient was identified by compatible signs and symptoms, roentgenographic studies, pulmonary function tests, and a transbronchial lung biopsy. She was further evaluated with a detailed environmental history, serologic tests, and investigation of the home environment. An environmental avoidance and challenge technique was performed to confirm cause and effect and to determine that remediation had been effective.

RESULTS

Review of the biopsy showed NSIP and failed to reveal any non-caseating granuloma formation. Investigation of the home revealed a Cladosporium species contamination of the air conditioning system and Penicillium species beneath an entryway carpet. Serum precipitins to commercial antigens of common mold to the south Texas area were negative. Avoidance and challenge techniques confirmed the home as the causative environment in this case of NSIP. The patient has been free of signs and symptoms and has taken no medication for interstitial lung disease over the past 30 months.

CONCLUSIONS

Some cases of NSIP may be caused by inhalation of microbial antigen(s) in a closed environment. An environmental challenge technique was an effective method to determine the causative environment and confirm that remediation had been effective. Inadequate remediation may lead to symptomatic improvement, but may convert a patient from an acute to an insidious presenter. The environmental challenge obviates a need for specific challenges to determine specific causation. Remediation of or moving from an environmental contamination to achieve reversibility or prevent progression was the treatment of choice to avoid use of long-term immunosuppressive agents.

Relief of sinus pain and pressure with fluticasone propionate aqueous nasal spray: a placebo-controlled trial in patients with allergic rhinitis

Although allergic rhinitis is commonly associated most with symptoms of nasal congestion, rhinorrhea, sneezing, and itching, the symptom of sinus pain and pressure often prompts the patient to seek medical attention. The effect of fluticasone propionate on this symptom has not been studied. The purpose of this study was to compare the efficacy and safety of fluticasone propionate aqueous nasal spray to placebo vehicle in the treatment of patients with sinus pain and pressure arising from allergic rhinitis. A multicenter, double-blind, parallel-group trial was conducted in 206 symptomatic patients > or = 12 years with seasonal or perennial allergic rhinitis. Patients were treated for 14 days with either fluticasone propionate aqueous nasal spray, 200 mcg once daily, or placebo vehicle. Patients attended clinic visits and kept diary cards rating sinus pain and pressure (measured as one symptom) and nasal congestion symptoms during the study. Treatment with fluticasone propionate provided significantly greater relief of symptoms of sinus pain and pressure compared with placebo over the entire 14-day treatment period. Nasal congestion scores also were significantly reduced compared with placebo at each time point. Treatments were well tolerated, and the incidence of adverse events attributable to study treatments was similar between groups. Our data indicate that symptoms of sinus pain and pressure and nasal congestion can be significantly reduced in patients with allergic rhinitis when treated with fluticasone propionate aqueous nasal spray, 200 mcg once daily.

Comparative efficacy, safety, and effect on quality of life of triamcinolone acetonide and fluticasone propionate aqueous nasal sprays in patients with fall seasonal allergic rhinitis

BACKGROUND

The topical potency of fluticasone propionate (FP) is known to be four times greater than that of triamcinolone acetonide (TAA). However, the significance of this difference has not been proven in the clinical treatment of seasonal allergic rhinitis (SAR).

OBJECTIVE

To compare the efficacy, safety, and effect on health-related quality of life (HRQL) of FP and TAA aqueous nasal sprays in patients with SAR.

METHODS

Single-blind, parallel-group, active-controlled design. Patients were randomized to 3-week treatment with TAA 220 microg (n = 172) or FP 200 microg (n = 180) as two sprays/nostril once daily AM. Twelve-hour reflective symptom evaluations (nasal discharge, stuffiness, itching; sneezing; ocular itching/tearing/redness) were performed AM/PM, beginning at pretreatment baseline period. Incidences of specific treatment-related side effects were collected in daily questionnaires. HRQL was evaluated at baseline and end-of-treatment with a validated disease-specific, quality-of-life instrument.

RESULTS

TAA and FP produced similar improvement in daily total nasal symptom scores overall (49.4% and 52.7%, respectively; P = 0.332) and at every weekly time point (P > 0.05). There were no significant differences between TAA and FP in any individual symptom score at any time point except week 2 (FP provided greater reduction in sneezing, P = 0.046). No significant difference was found between groups in overall occurrence of specific treatment-related side effects. Overall Rhinoconjunctivitis Quality of Life Questionnaire scores were similar for TAA and FP at end-of-treatment.

CONCLUSIONS

Despite differing molecular potencies, FP and TAA demonstrated comparable efficacy in the treatment of SAR, and produced similar occurrences of specific treatment-related side effects and similar improvements in overall patient HRQL.

Organic antigen-induced interstitial lung disease: diagnosis and management

BACKGROUND

Traditionally, chronic idiopathic interstitial pneumonia/fibrosis (IIP/F) had included usual interstitial pneumonia, desquamative interstitial pneumonia, and nonspecific interstitial pneumonia (NSIP). More recent classifications have included bronchiolitis obliterans-organizing pneumonia (BOOP), respiratory bronchiolitis-associated interstitial lung disease, and acute interstitial pneumonia. Some chronic eosinophilic pneumonias (CEP)/pulmonary infiltrate with eosinophilia (PIE) have obvious causes, but many lack an identifiable etiology. We felt that hypersensitivity pneumonitis (HP) was being underdiagnosed and was hidden within this large heterogeneous group of interstitial lung disorders of unrecognized cause.

OBJECTIVE

We sought to prove that detailed environmental histories and investigations would reveal causative contaminations in the home or workplace of some patients with idiopathic interstitial lung disease and remediation of the contamination would stabilize the disorder.

METHODS

Consecutive cases of IIP/F were investigated. Patients were identified by compatible signs and symptoms, roentgenographic studies, pulmonary function tests, and lung biopsies. They were further evaluated with detailed environmental histories, serologic tests, and investigation into the suspected causative environment. Environmental and specific antigen challenges were done in some cases. Remediation of contaminations or moving into another environment were the methods used as therapy.

RESULTS

Eighty-six consecutive patients with IIP/F were evaluated. Twelve patients were subsequently diagnosed with specific causes for interstitial lung disease. Fifty-seven of 74 patients were identified by clinical evaluation and lung biopsy with HP, CEP/PIE, NSIP, BOOP, UIP, and nonclassifiable morphologic patterns. Seventeen patients were not biopsied or had an inadequate transbronchial biopsy but had consistent findings radiographically and clinically of idiopathic interstitial lung disease. Contamination of the home was causative in 69 of 74 and the workplace in 3 of 74 cases. There were 9 positive and 33 negative environmental challenges with 4 positive and 1 negative specific challenges. Fifty of 74 (67%) patients are receiving no treatment and are free of active disease after remediation of the environmental contamination, with a mean survival of 8.2 years.

CONCLUSIONS

Our data show that UIP, BOOP, NSIP, CEP/PIE, and nonclassifiable morphologic patterns represent a spectrum of interstitial lung disease that may be caused by inhalation of organic dusts in the home or workplace as described with HP. Remediation of, or moving from the contamination, can lead to arrest of the active inflammatory process and stability of the lung disorder.

Hyperglucagonemia in rats results in decreased plasma homocysteine and increased flux through the transsulfuration pathway in liver

An elevated plasma level of homocysteine is a risk factor for the development of cardiovascular disease. The purpose of this study was to investigate the effect of glucagon on homocysteine metabolism in the rat. Male Sprague-Dawley rats were treated with 4 mg/kg/day (3 injections per day) glucagon for 2 days while control rats received vehicle injections. Glucagon treatment resulted in a 30% decrease in total plasma homocysteine and increased hepatic activities of glycine N-methyltransferase, cystathionine beta-synthase, and cystathionine gamma-lyase. Enzyme activities of the remethylation pathway were unaffected. The 90% elevation in activity of cystathionine beta-synthase was accompanied by a 2-fold increase in its mRNA level. Hepatocytes prepared from glucagon-injected rats exported less homocysteine, when incubated with methionine, than did hepatocytes of saline-treated rats. Flux through cystathionine beta-synthase was increased 5-fold in hepatocytes isolated from glucagon-treated rats as determined by production of (14)CO(2) and alpha-[1-(14)C]ketobutyrate from l-[1-(14)C]methionine. Methionine transport was elevated 2-fold in hepatocytes isolated from glucagon-treated rats resulting in increased hepatic methionine levels. Hepatic concentrations of S-adenosylmethionine and S-adenosylhomocysteine, allosteric activators of cystathionine beta-synthase, were also increased following glucagon treatment. These results indicate that glucagon can regulate plasma homocysteine through its effects on the hepatic transsulfuration pathway.

Methylation demand and homocysteine metabolism: effects of dietary provision of creatine and guanidinoacetate

S-adenosylmethionine, formed by the adenylation of methionine via S-adenosylmethionine synthase, is the methyl donor in virtually all known biological methylations. These methylation reactions produce a methylated substrate and S-adenosylhomocysteine, which is subsequently metabolized to homocysteine. The methylation of guanidinoacetate to form creatine consumes more methyl groups than all other methylation reactions combined. Therefore, we examined the effects of increased or decreased methyl demand by these physiological substrates on plasma homocysteine by feeding rats guanidinoacetate- or creatine-supplemented diets for 2 wk. Plasma homocysteine was significantly increased (~50%) in rats maintained on guanidinoacetate-supplemented diets, whereas rats maintained on creatine-supplemented diets exhibited a significantly lower (~25%) plasma homocysteine level. Plasma creatine and muscle total creatine were significantly increased in rats fed the creatine-supplemented or guanidinoacetate-supplemented diets. The activity of kidney L-arginine:glycine amidinotransferase, the enzyme catalyzing the synthesis of guanidinoacetate, was significantly decreased in both supplementation groups. To examine the role of the liver in mediating these changes in plasma homocysteine, isolated rat hepatocytes were incubated with methionine in the presence and absence of guanidinoacetate and creatine, and homocysteine export was measured. Homocysteine export was significantly increased in the presence of guanidinoacetate. Creatine, however, was without effect. These results suggest that homocysteine metabolism is sensitive to methylation demand imposed by physiological substrates.