International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Interleukin-33 activates regulatory T cells to suppress innate γδ T cell responses in the lung

Foxp3⁺ regulatory T (T_reg) cells expressing the interleukin (IL)-33 receptor ST2 mediate tissue repair in response to IL-33. Whether T_reg cells also respond to the alarmin IL-33 to regulate specific aspects of the immune response is not known. Here we describe an unexpected function of ST2⁺ T_reg cells in suppressing the innate immune response in the lung to environmental allergens without altering the adaptive immune response. Following allergen exposure, ST2⁺ T_reg cells were activated by IL-33 to suppress IL-17-producing γδ T cells. ST2 signaling in T_reg cells induced Ebi3, a component of the heterodimeric cytokine IL-35 that was required for T_reg cell-mediated suppression of γδ T cells. This response resulted in fewer eosinophil-attracting chemokines and reduced eosinophil recruitment into the lung, which was beneficial to the host in reducing allergen-induced inflammation. Thus, we define a fundamental role for ST2⁺ T_reg cells in the lung as a negative regulator of the early innate γδ T cell response to mucosal injury.

Dupilumab reduces opacification across all sinuses and related symptoms in patients with CRSwNP

BACKGROUND

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is associated with substantial sinus opacification. In a phase 2a study (NCT01920893), dupilumab, a fully human anti-IL-4Rα monoclonal antibody, improved outcomes in CRSwNP refractory to intranasal corticosteroids. We evaluated dupilumab’s effect on sinus opacification in relation to effects on nasal polyp burden, symptoms, and health-related quality of life (HRQoL) in patients with CRSwNP.

METHODOLOGY

16-week randomized, double-blind, placebo-controlled, parallel-group study in 60 adults with CRSwNP. Patients received weekly subcutaneous dupilumab 300-mg or placebo and daily mometasone furoate nasal spray. Sinus opacification was assessed using standard and Zinreich-modified Lundâ€"Mackay (zLMK) scoring. Correlation was assessed between zLMK score and CRSwNP endpoints, including nasal polyp score (NPS), SNOT-22, daily symptom scores, and UPSIT smell-test score.

RESULTS

Baseline characteristics were similar across treatment groups. Mean plus/minus SD baseline LMK scores of 18.7 plus/minus 5.5 (placebo) and 18.6 plus/minus 5.0 (dupilumab) indicated severe disease with extensive opacification involving all sinuses. Baseline LMK and LMK scores correlated with NPS severity and loss of sense of smell (daily symptoms; SNOT-22 smell/taste; loss of sense of smell [UPSIT]). At Week 16, dupilumab-treated patients had significantly improved sinus opacification measured by LMK in all individual sinuses vs placebo. Dupilumab also showed similar efficacy with zLMK, with only small differences from LMK, and correlated with SNOT22 smell/taste. The most common adverse events were nasopharyngitis, injection-site reactions, and headache.

CONCLUSIONS

In patients with CRSwNP, baseline LMK showed extensive sinus opacification and correlated with symptoms, HRQoL, and hyposmia. Dupilumab treatment reduces opacification across all sinuses and related symptoms in patients with CRSwNP.

Dupilumab improves health-related quality of life in patients with chronic rhinosinusitis with nasal polyposis

BACKGROUND

Chronic rhinosinusitis with nasal polyposis (CRSwNP) negatively affects health-related quality of life (HRQoL). In a previously reported randomized clinical trial (NCT01920893), addition of dupilumab to mometasone furoate in patients with CRSwNP refractory to intranasal corticosteroids (INCS) significantly improved endoscopic, radiographic, and clinical endpoints and patient-reported outcomes. The objective of this analysis was to examine the impact of dupilumab treatment on HRQoL and productivity using secondary outcome data from this trial.

METHODS

Following a 4-week mometasone furoate nasal spray run-in, patients were randomized to commence subcutaneous dupilumab (600 mg loading dose, then 300 mg once weekly for 15 weeks [n = 30], or matched placebo [n = 30]). Outcomes included scores on the CRS disease severity visual analog scale (VAS), 22-item Sino-Nasal Outcome Test (SNOT-22), 5-dimension EuroQoL (EQ-5D) general health status VAS, and 36-item Short-Form Health Survey (SF-36) for HRQoL and nasal polyp-related healthcare resource use questionnaires.

RESULTS

Following 16 weeks of treatment, the proportion of patients with moderate-to-severe CRSwNP (VAS > 3-10) decreased from 86.2% to 21.4% with dupilumab and 88.0% to 84.2% with placebo. Dupilumab (vs placebo) resulted in significantly greater improvement in HRQoL, based on SNOT-22, SF-36, and EQ-5D VAS scores. The dupilumab group had a significantly lower adjusted annualized mean number of sick leave days (0.09, vs 4.18 with placebo, P = .015) and significantly greater improvement (vs placebo) in the SNOT-22 item "reduced productivity."

CONCLUSIONS

In adults with CRSwNP refractory to treatment with INCS alone, the addition of dupilumab reduced disease severity, significantly improved HRQoL, and improved productivity.

Quantitative assessment of airway remodelling and response to allergen in asthma

BACKGROUND AND OBJECTIVE

In vivo evaluation of the microstructural differences between asthmatic and non-asthmatic airways and their functional consequences is relevant to understanding and, potentially, treating asthma. In this study, we use endobronchial optical coherence tomography to investigate how allergic airways with asthma differ from allergic non-asthmatic airways in baseline microstructure and in response to allergen challenge.

METHODS

A total of 45 subjects completed the study, including 20 allergic, mildly asthmatic individuals, 22 non-asthmatic allergic controls and 3 healthy controls. A 3-cm airway segment in the right middle and right upper lobe were imaged in each subject immediately before and 24 h following segmental allergen challenge to the right middle lobe. Relationships between optical airway measurements (epithelial and mucosal thicknesses, mucosal buckling and mucus) and airway obstruction (FEV1 /FVC (forced expiratory volume in 1 s/forced vital capacity) and FEV1 % (FEV1 as a percentage of predictive value)) were investigated.

RESULTS

Significant increases at baseline and in response to allergen were observed for all four of our imaging metrics in the asthmatic airways compared to the non-asthmatic airways. Epithelial thickness and mucosal buckling exhibited a significant relationship to FEV1 /FVC in the asthmatic group.

CONCLUSION

Simultaneous assessments of airway microstructure, buckling and mucus revealed both structural and functional differences between the mildly asthmatic and control groups, with airway buckling seeming to be the most relevant factor. The results of this study demonstrate that a comprehensive, microstructural approach to assessing the airways may be important in future asthma studies as well as in the monitoring and treatment of asthma.

Biofilm Formations in Pediatric Respiratory Tract Infection : Part 1: Biofilm Structure, Role of Innate Immunity in Protection Against and Response to Biofilm, Methods of Biofilm Detection, Pediatric Respiratory Tract Diseases Associated with Mucosal Biofilm Formation

PURPOSE OF REVIEW

Biofilm represents an organized structure of microorganisms within an extracellular matrix attached to a surface. While the importance of biofilm in prosthetic heart valve and catheter-related infections has been known since the 1980s, the role of mucosal biofilm in human disease pathogenesis has only recently been elucidated. It is now clear that mucosal biofilm is present in both healthy and pathologic states. The purpose of this review is to examine the role of mucosal biofilm in pediatric respiratory infections.

RECENT FINDINGS

Mucosal biofilm has been implicated in relationship to several pediatric respiratory infections, including tonsillitis, adenoiditis, otitis media with effusion, chronic rhinosinusitis, persistent endobronchial infection, and bronchiectasis. In these conditions, core pathogens are detected in the biofilm, biofilm organisms are often detected by molecular techniques when conventional cultures are negative, and biofilm presence is more extensive in relation to disease than in healthy tissues. In chronic rhinosinusitis, the presence of polymicrobial biofilm is also a predictor of poorer outcome following sinus surgery. Biofilm in the tonsillar and adenoidal compartments plays a distinct role in contributing to disease in the middle ear and sinuses. Key observations regarding the relevance of biofilm to pediatric respiratory infections include (1) the association between the presence of biofilm and persistent/recurrent and more severe disease in these tissues despite antibiotic treatment, (2) linkage between biofilm core pathogens and acute infections, and (3) interrelationship between biofilm presence in one tissue and persistent or recurrent infection in an adjacent tissue. A greater understanding of the significance of mucosal biofilm will undoubtedly emerge with the development of effective means of eradicating mucosal biofilm.

Chronic Rhinosinusitis Patients with Polyps or Polypoid Mucosa have a Greater Burden of Illness

Background

Recent studies suggest chronic rhinosinusitis without nasal polyposis (CRSsNP) and CRS with nasal polyposis (CRScNP) represent distinct pathological entities. The aim of this study was to determine whether patients with CRSsNP, CRScNP, and polypoid CRS could be distinguished by clinical features, radiologic extent of disease or use of medications.

Methods

New patients with CRS (n = 126) were enrolled in a prospective outcomes study. Rhinoscopic evaluation was used to classify patients. The relationship between disease phenotype and clinical parameters was examined.

Results

Facial pain/pressure/headache was more prevalent in CRSsNP than CRScNP (p = 0.01). Nasal obstruction and hyposmia/ anosmia were more prevalent in CRScNP than CRSsNP (p = 0.025 and 0.01, respectively). Intermediate symptom prevalence was found in polypoid CRS. Multivariate analysis confirmed that prior surgery, CT scan score, and male gender were independent predictors of polyp/polypoid phenotype. Allergic status was unrelated to CRS classification. Medication use was higher in CRScNP patients than in CRSsNP patients.

Conclusion

Compared with CRSsNP, patients with CRScNP have a greater burden of symptoms, more prior surgery, higher CT scan scores, and greater use of medications.

Clinical Outcomes of Chronic Rhinosinusitis in Response to Medical Therapy: Results of a Prospective Study

Background

Little information exists regarding the outcome of medical management of chronic rhinosinusitis (CRS) in adults. The aim of this study was to examine whether baseline patient demographics, symptoms, objective findings, or treatment strategies were associated with improved CRS outcomes over time.

Methods

Eighty-four new patients with CRS were evaluated and medically treated for up to 12 months. Patients completed monthly health status questionnaires. The average change of symptom scores using the Sino-Nasal Outcome Test plus one additional symptom–-sense of smell (SNOT-20+1)–-was the primary outcome measure.

Results

Overall, patients experienced a modest improvement in SNOT-20+1 scores (Δ = -0.61; p< 0.0001), but this did not reach the predetermined level of a clinically meaningful effect (Δ = -0.80). Baseline facial pain or facial pressure was negatively associated with outcome (p = 0.048 and 0.029, respectively) and did not correlate with extent of disease by sinus CT scoring. Other factors, including nasal discharge, hyposmia, cough, nasal polyps, and sinus CT severity, did not predict outcomes. The use of either oral antibiotics or oral steroids was associated with trends toward improved outcomes only when sinus-specific symptoms alone were considered.

Conclusion

The majority of CRS patients receiving medical treatment show modest improvement over time in SNOT-20+1 scores. Facial pain or facial pressure at entry are negatively associated with outcomes and may reflect causes other than CRS. These findings highlight the limitations of current medical treatment for CRS and the need for novel treatment strategies.

Allergic asthma is distinguished by sensitivity of allergen-specific CD4+ T cells and airway structural cells to type 2 inflammation

Despite systemic sensitization, not all allergic individuals develop asthma symptoms upon airborne allergen exposure. Determination of the factors that lead to the asthma phenotype in allergic individuals could guide treatment and identify novel therapeutic targets. We used segmental allergen challenge of allergic asthmatics (AA) and allergic nonasthmatic controls (AC) to determine whether there are differences in the airway immune response or airway structural cells that could drive the development of asthma. Both groups developed prominent allergic airway inflammation in response to allergen. However, asthmatic subjects had markedly higher levels of innate type 2 receptors on allergen-specific CD4⁺ T cells recruited into the airway. There were also increased levels of type 2 cytokines, increased total mucin, and increased mucin MUC5AC in response to allergen in the airways of AA subjects. Furthermore, type 2 cytokine levels correlated with the mucin response in AA but not AC subjects, suggesting differences in the airway epithelial response to inflammation. Finally, AA subjects had increased airway smooth muscle mass at baseline measured in vivo using novel orientation-resolved optical coherence tomography. Our data demonstrate that the development of allergic asthma is dependent on the responsiveness of allergen-specific CD4⁺ T cells to innate type 2 mediators as well as increased sensitivity of airway epithelial cells and smooth muscle to type 2 inflammation.

Birefringence microscopy platform for assessing airway smooth muscle structure and function in vivo

The inability to visualize airway smooth muscle (ASM) cells in vivo is a major obstacle in understanding their role in normal physiology and diseases. At present, there is no imaging modality available to assess ASM in vivo. Confocal endomicroscopy lacks the penetration depth and field of view, and conventional optical coherence tomography (OCT) does not have sufficient contrast to differentiate ASM from surrounding tissues. We have developed a birefringence microscopy platform that leverages the micro-organization of tissue to add further dimension to traditional OCT. We have used this technology to validate ASM measurements in ex vivo swine and canine studies, visualize and characterize volumetric representations of ASM in vivo, and quantify and predict ASM contractile force as a function of optical retardation. We provide in vivo images and volumetric assessments of ASM in living humans and document structural disease variations in subjects with mild asthma. The opportunity to link inflammatory responses to ASM responses and to link ASM responses to clinical responses and outcomes could lead to an increased understanding of diseases of the airway and, ultimately, to improved patient outcomes.

Automated segmentation and quantification of airway mucus with endobronchial optical coherence tomography

We propose a novel suite of algorithms for automatically segmenting the airway lumen and mucus in endobronchial optical coherence tomography (OCT) data sets, as well as a novel approach for quantifying the contents of the mucus. Mucus and lumen were segmented using a robust, multi-stage algorithm that requires only minimal input regarding sheath geometry. The algorithm performance was highly accurate in a wide range of airway and noise conditions. Mucus was classified using mean backscattering intensity and grey level co-occurrence matrix (GLCM) statistics. We evaluated our techniques in vivo in asthmatic and non-asthmatic volunteers.

Recent advances in understanding and managing IgG4-related disease

IgG4-related disease was only recently discovered, so its description, management, and new discoveries related to its etiology are rapidly evolving. Because IgG4 itself is a unique antibody which is intimately related to the diagnosis of the disease, the role of plasmablasts in the pathophysiology remains an active area of discussion. Recent studies have uncovered a possible role for CD4-positive cytotoxic T lymphocytes, T follicular helper cells, and M2 macrophages. The clinical presentation is variable and can be vague, as this disease affects many organs and new presentations are continuing to be described. The diagnosis depends on clinical and histopathological assessment. The mainstay of treatment is with glucocorticoids, but rituximab has recently shown promise. Monitoring disease activity using imaging modalities (including positron emission tomography) and serum markers is imperative, as relapses are common. IgG4-related disease spans many medical disciplines but is a treatable condition with which all clinicians should be familiar.

Problem-based learning discussion: Medical treatment of pediatric chronic rhinosinusitis

This problem-based learning case focused on the approach to evaluation and management of a 5-year old girl who was "always sick" with sinus infections. The discussion unfolds in a "real life" scenario, i.e., based on information available to the clinician initially and after the acquisition of laboratory data, and, ultimately, after sinus surgery. Emphasis is placed on the differential diagnosis of the patient's symptoms, discussion of the initial management strategy for chronic rhinosinusitis (CRS), evolution from acute rhinosinusitis to CRS, the prevalence of and differential diagnosis of nasal polyps in children, treatment considerations specific for CRS with nasal polyps, the significance of Pseudomonas aeruginosa sinus infection, the significance of an abnormal sweat chloride test in a young child with nasal polyposis, special considerations in children with CRS who have cystic fibrosis, treatment considerations after endoscopic sinus surgery, and, finally, prognostic factors that impact the outcomes of endoscopic sinus surgery. This problem-based learning case highlights many facets of managing refractory CRS in children.

Etiology of Chronic Rhinosinusitis: The Role of Fungus

Chronic rhinosinusitis (CRS) is a multifactorial disease. Predisposing factors can be divided into environmental and non-host factors, such as pollution, viral infections, smoking, fungus, and bacteria; general host factors, including genetic factors and immune deficiency; and local host factors, including persistent focal inflammation within the ostiomeatal complex. Evidence suggests that the underlying bone in the ostiomeatal complex is actively involved in the disease process of CRS. The evidence concerning a broad range of predisposing factors for CRS is reviewed. Chronic rhinosinusitis is an inflammatory disorder with numerous predisposing factors, including genetics, pollution, anatomic anomalies, bacteria, and fungus. In some studies, fungi have been cultured from nearly 100% of patients with rhinosinusitis and nasal polyposis. T-cell sensitization to fungus with production of the T-helper 2 (Th2) cytokine interleukin-5 has been proposed as a key step in the initiation of the disease. Interleukin-5 also plays an important role in the effector phase of the disease through its effects on eosinophilopoesis and eosinophil survival. There is considerable controversy concerning the role of fungi as the cause of “chronic eosinophilic rhinosinusitis” and whether this even represents a distinct clinical entity. Further study is also required to define the optimal treatment for the disease.

Pediatric chronic rhinosinusitis

The goal of this review is to elucidate the pathogenic factors, histopathologic features, and special considerations that relate to pediatric versus adult chronic rhinosinusitis (CRS) and to emphasize differences and similarities between the adult and pediatric conditions. Emphasis is placed on understanding of the differences in pathogenic mechanisms, host-microbial interactions, potential defects in innate antimicrobial immunity, and the role of biofilm formation in pediatric versus adult CRS and how these translate to different approaches toward both medical and surgical management. Pediatric CRS can be viewed as evolving from acute bacterial rhinosinusitis into an uncomplicated "early" stage of CRS, later evolving into a persistent stage and, in some cases, evolving into a late "maladaptive-eosinophilic" stage disease. Given this potential evolution toward more irreversible disease, a plea can be made for improved recognition of and more aggressive early intervention for pediatric CRS, it is hoped, to prevent these long-term consequences. For the primary care physician, this may necessitate enlisting the support of a sinus specialist before the symptoms of CRS have persisted for months or years. It may also necessitate, in some cases, the use of sinus computed tomography imaging to demonstrate that sinus abnormalities have resolved. Other arguments can be made for prompt and comprehensive management of pediatric CRS, including the need to reduce the burden of illness, reduce health care costs, avoid unnecessary antibiotic use and its attendant effects toward promoting antibiotic resistant infections and, potentially, to reduce the development of important comorbidities, e.g., asthma.

Drivers of chronic rhinosinusitis: Inflammation versus infection

Studies of the underlying cause or causes of chronic rhinosinusitis (CRS) over the past 20 or more years have expanded from a focus on systemic immune and allergic mechanisms to an intense search for the underlying drivers of mucosal inflammation. These drivers involve mucosal inflammatory pathways that become activated by allergens, microbial stimuli, or poorly understood exogenous or endogenous stimuli. The holy grail in the study of CRS is to identify specific drivers of mucosal inflammation and translate these into more effective treatment for CRS. Certain deficiencies in local innate immunity have been described in patients with CRS that predispose to increased sinus mucosal bacterial colonization/infection, including deficient local production of antimicrobial lactoferrin and deficient functioning of the bitter taste receptor TAS2R38. Conversely, certain innate factors, namely IL-25, IL-33, and thymic stromal lymphopoietin (TSLP), are elaborated by sinus epithelial cells in response to microbial stimulation or airway injury and promote local TH2 inflammation. The precise physiologic role of these factors in innate or adaptive immunity is unclear, although IL-33 might function as an alarmin triggered by damage-associated molecular patterns. The cytokines IL-25 and TSLP, similarly promote proinflammatory tissue responses. Another feature of epithelial dysregulation in patients with CRS is overproduction of eosinophil-promoting C-C chemokines by sinus epithelium, perhaps driven in part through innate stimuli, as well as TH2 cytokines, such as IL-13. Strategies to reduce the microbial stimulation of maladaptive TH2 inflammation or to suppress the local elaboration of TH2-promoting epithelial factors, such as IL-33, have potential therapeutic benefit in patients with CRS, although the extent to which this is realized in patient care remains limited at present. This rostrum will summarize my views on the major microbial drivers of mucosal inflammation and dysregulation of innate TH2-promoting factors in patients with CRS based on recent experimental data.

Allergic Non-Asthmatic Adults Have Regional Pulmonary Responses to Segmental Allergen Challenge

Background

Allergic non-asthmatic (ANA) adults experience upper airway symptoms of allergic disease such as rhinorrhea, congestion and sneezing without symptoms of asthma. The aim of this study was to utilize PET-CT functional imaging to determine whether allergen challenge elicits a pulmonary response in ANA subjects or whether their allergic disease is truly isolated to the upper airways.

Methods

In 6 ANA subjects, bronchoalveolar lavages (BAL) were performed at baseline and 24h after instillation of an allergen and a diluent in separate lung lobes. After instillation (10h), functional imaging was performed to quantify and compare regional perfusion, ventilation, fractional gas content (Fgas), and glucose uptake rate (Ki) between the baseline, diluent and allergen lobes. BAL cell counts were also compared.

Results

In ANA subjects, compared to the baseline and diluent lobes, perfusion and ventilation were significantly lower in the allergen lobe (median [inter-quartile range], baseline vs. diluent vs. allergen: Mean-normalized perfusion; 0.87 [0.85–0.97] vs. 0.90 [0.86–0.98] vs. 0.59 [0.55–0.67]; p<0.05. Mean-normalized ventilation 0.89 [0.88–0.98] vs. 0.95 [0.89–1.02] vs. 0.63 [0.52–0.67], p<0.05). In contrast, no significant differences were found in Fgas between baseline, diluent and allergen lobes or in Ki. Total cell counts, eosinophil and neutrophil cell counts (cells/ml BAL) were significantly greater in the allergen lobe compared to the baseline lobe (all P<0.05).

Conclusions

Despite having no clinical symptoms of a lower airway allergic response (cough and wheeze) allergic non-asthmatic subjects have a pulmonary response to allergen exposure which manifests as reduced ventilation and perfusion.

Profibrotic transforming growth factor beta 1 and activin A are increased in nasal polyp tissue and induced in nasal polyp epithelium by cigarette smoke and Toll-like receptor 3 ligation

BACKGROUND

The mechanism of airway remodeling in chronic rhinosinusitis with nasal polyposis (CRSwNP) remains unknown. We wished to determine whether profibrotic transforming growth factor beta 1 (TGF-β1) and activin A and their downstream signaling proteins are increased in CRSwNP and if they are regulated in epithelial cells by noxious or inflammatory stimuli.

METHODS

Frozen tissue from CRSwNP patients, healthy control (HC) middle turbinates, and sinus tissue from CRS without NP (CRSsNP) patients were immunostained for TGF-β1, activin A, and downstream signaling proteins. Primary nasal epithelial cells (PNECs) from HCs and CRSwNP patients were cultured in media, cigarette smoke extract (CSE), or double-stranded RNA (dsRNA) (a ligand for Toll-like receptor-3) and examined for inflammatory and profibrotic genes using real-time polymerase chain reaction (PCR).

RESULTS

CRSwNP patients showed increased TGF-β1 and activin A in the stroma, increased TGF-β1 signaling (phosphorylated Smad2/3) in the stroma and epithelium, and increased Smad3-dependent Snail1 in the stroma. Immunostaining for TGF-β1, pSmad2/3, and Snail1 in CRSwNP patients was highly correlated. Immunostaining for pSmad2/3 and Snail1 was similar in CRSwNP and CRSsNP patients. Compared to HCs, PNECs from CRSwNP patients were more responsive to CSE and dsRNA in terms of TGF-β1 and activin A and more strongly induced by dsRNA in terms of chemokines.

CONCLUSION

Increased TGF-β1 and activin A and increased downstream TGF-β1 signaling is present in CRSwNP patients, primarily in the stroma. This may contribute to features of airway remodeling previously described. PNECs from CRSwNP patients are induced to produce TGF-β1 and activin A by CSE and dsRNA, suggesting that cigarette smoke and viral infection might also contribute to airway remodeling.

The nasal and sinus microbiome in health and disease

There has been great interest in unraveling the complex inter-relationships between microbes and humans as they relate to human health and disease. This review will focus on recent advances in the appreciation and understanding of these relationships in terms of the upper respiratory tract, specifically the nose and paranasal sinuses.

ICON: chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a public health problem that has a significant socio-economic impact. Moreover, the complexity of this disease due to its heterogeneous nature based on the underlying pathophysiology - leading to different disease variants - further complicates our understanding and directions for the most appropriate targeted treatment strategies. Several International/national guidelines/position papers and/or consensus documents are available that present the current knowledge and treatment strategies for CRS. Yet there are many challenges to the management of CRS especially in the case of the more severe and refractory forms of disease. Therefore, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), a collaboration between EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus (ICON) on Chronic Rhinosinusitis. The purpose of this ICON on CRS is to highlight the key common messages from the existing guidelines, the differences in recommendations as well as the gaps in our current knowledge of CRS, thus providing a concise reference. In this document we discuss the definition of the disease, its relevance, pharmacoeconomics, pathophysiology, phenotypes and endotypes, genetics and risk factors, natural history and co-morbidities as well as clinical manifestations and treatment options in both adults and children comprising pharmacotherapy, surgical interventions and more recent biological approaches. Finally, we have also highlighted the unmet needs that wait to be addressed through future research.

Host-microbial interactions in patients with chronic rhinosinusitis

There has been considerable investigation of host-microbial interactions in patients with chronic rhinosinusitis (CRS) in hopes of elucidating mechanisms of disease and better treatment. Most attention has been paid to bacterial infection and potential underlying defects in innate immunity. Bacterial biofilm is present in most patients with CRS undergoing surgical intervention, and its presence is associated with more severe disease and worse surgical outcomes. A role for viral or fungal infection in patients with CRS is less clear. There is no evidence for a primary defect in mucociliary clearance in most patients with CRS. Decreased levels of certain antimicrobial proteins, most notably lactoferrin, have been found in sinus secretions, whereas levels of other antimicrobial proteins have been found to be normal. No primary defects in Toll-like receptors have been found in patients with CRS, although a 50% reduced expression of Toll-like receptor 9 was reported in patients with recalcitrant nasal polyps. A polymorphism in a bitter taste receptor was recently associated with refractory CRS and persistent Pseudomonas aeruginosa infection. A downregulation of innate immunity by maladaptive T_H2 tissue inflammation has also been described in patients with recalcitrant nasal polyps, suggesting a link to persistent infection. To date, an effective means of restoring host-microbial balance and mitigating disease in patients with CRS remains elusive.

Compartmentalized chemokine-dependent regulatory T-cell inhibition of allergic pulmonary inflammation

BACKGROUND

Induction of endogenous regulatory T (Treg) cells represents an exciting new potential modality for treating allergic diseases, such as asthma. Treg cells have been implicated in the regulation of asthma, but the anatomic location in which they exert their regulatory function and the mechanisms controlling the migration necessary for their suppressive function in asthma are not known. Understanding these aspects of Treg cell biology will be important for harnessing their power in the clinic.

OBJECTIVE

We sought to determine the anatomic location at which Treg cells exert their regulatory function in the sensitization and effector phases of allergic asthma and to determine the chemokine receptors that control the migration of Treg cells to these sites in vivo in both mice and human subjects.

METHODS

The clinical efficacy and anatomic location of adoptively transferred chemokine receptor-deficient CD4(+)CD25(+) forkhead box protein 3-positive Treg cells was determined in the sensitization and effector phases of allergic airway inflammation in mice. The chemokine receptor expression profile was determined on Treg cells recruited into the human airway after bronchoscopic segmental allergen challenge of asthmatic patients.

RESULTS

We show that CCR7, but not CCR4, is required on Treg cells to suppress allergic airway inflammation during the sensitization phase. In contrast, CCR4, but not CCR7, is required on Treg cells to suppress allergic airway inflammation during the effector phase. Consistent with our murine studies, human subjects with allergic asthma had an increase in CCR4-expressing functional Treg cells in the lungs after segmental allergen challenge.

CONCLUSION

The location of Treg cell function differs during allergic sensitization and allergen-induced recall responses in the lung, and this differential localization is critically dependent on differential chemokine function.

Consensus statement on the pathology of IgG4-related disease

IgG4-related disease is a newly recognized fibro-inflammatory condition characterized by several features: a tendency to form tumefactive lesions in multiple sites; a characteristic histopathological appearance; and-often but not always-elevated serum IgG4 concentrations. An international symposium on IgG4-related disease was held in Boston, MA, on 4-7 October 2011. The organizing committee comprising 35 IgG4-related disease experts from Japan, Korea, Hong Kong, the United Kingdom, Germany, Italy, Holland, Canada, and the United States, including the clinicians, pathologists, radiologists, and basic scientists. This group represents broad subspecialty expertise in pathology, rheumatology, gastroenterology, allergy, immunology, nephrology, pulmonary medicine, oncology, ophthalmology, and surgery. The histopathology of IgG4-related disease was a specific focus of the international symposium. The primary purpose of this statement is to provide practicing pathologists with a set of guidelines for the diagnosis of IgG4-related disease. The diagnosis of IgG4-related disease rests on the combined presence of the characteristic histopathological appearance and increased numbers of IgG4⁺ plasma cells. The critical histopathological features are a dense lymphoplasmacytic infiltrate, a storiform pattern of fibrosis, and obliterative phlebitis. We propose a terminology scheme for the diagnosis of IgG4-related disease that is based primarily on the morphological appearance on biopsy. Tissue IgG4 counts and IgG4:IgG ratios are secondary in importance. The guidelines proposed in this statement do not supplant careful clinicopathological correlation and sound clinical judgment. As the spectrum of this disease continues to expand, we advocate the use of strict criteria for accepting newly proposed entities or sites as components of the IgG4-related disease spectrum.

18F-FDG uptake rate is a biomarker of eosinophilic inflammation and airway response in asthma

In asthma, the relationship among airway inflammation, airway hyperresponsiveness, and lung function is poorly understood. Methods to noninvasively assess these relationships in human subjects are needed. We sought to determine whether (18)F-FDG uptake rate (K(i), min(-1)) could serve as a biomarker of eosinophilic inflammation and local lung function.

METHODS

We used PET/CT to assess regional pulmonary perfusion (Q), specific ventilation per unit volume (sV(A)), fractional gas content (Fgas), airway wall thickness, and regional K(i) 10 h after segmental allergen challenge to the right middle lobe in 6 asthmatic subjects with demonstrated atopy. Q, sV(A), and Fgas in the allergen-challenged lobe were compared with the right upper lobe, where diluent was applied as a control. The airway wall thickness aspect ratio (ω) of the allergen-challenged airway was compared with those of similarly sized airways from unaffected areas of the lung. Differences in K(i) between allergen and diluent segments were compared with those in cell counts obtained 24 h after the allergen challenge by a bronchoalveolar lavage of the respective segments.

RESULTS

We found systematic reductions in regional Q, sV(A), and Fgas and increased ω in all subjects. The ratio of eosinophil count (allergen to diluent) was linearly related (R(2) = 0.9917, P < 0.001) to the ratio of K(i).

CONCLUSION

Regional K(i) measured with PET is a noninvasive and highly predictive biomarker of eosinophilic airway inflammation and its functional effects. This method may serve to help in the understanding of allergic inflammation and test the therapeutic effectiveness of novel drugs or treatments.

Omalizumab in severe allergic asthma inadequately controlled with standard therapy: a randomized trial

BACKGROUND

Inhaled corticosteroids (ICS) and long-acting β(2)-agonists (LABAs) are recommended in patients with asthma that is not well-controlled; however, many patients continue to have inadequately controlled asthma despite this therapy.

OBJECTIVE

To evaluate the efficacy and safety of omalizumab in patients with inadequately controlled severe asthma who are receiving high-dose ICS and LABAs, with or without additional controller therapy.

DESIGN

Prospective, multicenter, randomized, parallel-group, double-blind, placebo-controlled trial. (ClinicalTrials.gov registration number: NCT00314575).

SETTING

193 investigational sites in the United States and 4 sites in Canada.

PATIENTS

850 patients aged 12 to 75 years who had inadequately controlled asthma despite treatment with high-dose ICS plus LABAs, with or without other controllers.

INTERVENTION

Omalizumab (n = 427) or placebo (n = 423) was added to existing medication regimens for 48 weeks.

MEASUREMENTS

The primary end point was the rate of protocol-defined exacerbations over the study period. Secondary efficacy end points included the change from baseline to week 48 in mean daily number of puffs of albuterol, mean total asthma symptom score, and mean overall score on the standardized version of the Asthma Quality of Life Questionnaire (AQLQ[S]). Safety end points included the frequency and severity of treatment-emergent adverse events.

RESULTS

During 48 weeks, the rate of protocol-defined asthma exacerbations was significantly reduced for omalizumab compared with placebo (0.66 vs. 0.88 per patient; P = 0.006), representing a 25% relative reduction (incidence rate ratio, 0.75 [95% CI, 0.61 to 0.92]). Omalizumab improved mean AQLQ(S) scores (0.29 point [CI, 0.15 to 0.43]), reduced mean daily albuterol puffs (-0.27 puff/d [CI, -0.49 to -0.04 puff/d]), and decreased mean asthma symptom score (-0.26 [CI, -0.42 to -0.10]) compared with placebo during the 48-week study period. The incidence of adverse events (80.4% vs. 79.5%) and serious adverse events (9.3% vs. 10.5%) were similar in the omalizumab and placebo groups, respectively.

LIMITATIONS

The results are limited by early patient discontinuation (20.8%). The study was not powered to detect rare safety events or the treatment effect in the oral corticosteroid subgroup.

CONCLUSION

In this study, omalizumab provided additional clinical benefit for patients with severe allergic asthma that is inadequately controlled with high-dose ICS and LABA therapy.

PRIMARY FUNDING SOURCE

Genentech and Novartis Pharmaceuticals.

Rhinosinusitis diagnosis and management for the clinician: a synopsis of recent consensus guidelines

Rhinosinusitis (RS) affects approximately 1 in 7 adults in the United States, and its effect on quality of life, productivity, and finances is substantial. During the past 10 years, several expert panels from authoritative bodies have published evidence-based guidelines for the diagnosis and management of RS and its subtypes, including acute viral RS, acute bacterial RS, chronic RS (CRS) without nasal polyposis, CRS with nasal polyposis, and allergic fungal RS. This review examines and compares the recommendations of the Rhinosinusitis Initiative, the Joint Task Force on Practice Parameters, the Clinical Practice Guideline: Adult Sinusitis, the European Position Paper on Rhinosinusitis and Nasal Polyps 2007, and the British Society for Allergy and Clinical Immunology. Points of consensus and divergent opinions expressed in these guidelines regarding classification, diagnosis, and management of adults with acute RS (ARS) and CRS and their various subtypes are highlighted for the practicing clinician. Key points of agreement regarding therapy in the guidelines for ARS include the efficacy of symptomatic treatment, such as intranasal corticosteroids, and the importance of reducing the unnecessary use of antibiotics in ARS; however, guidelines do not agree precisely regarding when antibiotics should be considered as a reasonable treatment strategy. Although the guidelines diverge markedly on the management of CRS, the diagnostic utility of nasal airway examination is acknowledged by all. Important and relevant data from MEDLINE-indexed articles published since the most recent guidelines were issued are also considered, and needs for future research are discussed.

Mutations in ribosomal proteins and ribosomal RNA confer macrolide resistance in human Ureaplasma spp

Genetic mechanisms of macrolide resistance were investigated in six isolates of Ureaplasma spp. with erythromycin minimum inhibitory concentrations (MICs)≥ 8 μg/mL that were derived from 370 cultures obtained over a several year period. Point mutations in domain V of 23S rRNA and/or mutations in ribosomal protein L4 genes are likely to be responsible for this drug resistance. Overall, macrolide resistance was uncommon, in contrast to tetracycline resistance that was documented in 121 unique isolates (33%).

Current Thinking on the Relationship Between Rhinosinusitis and Asthma

An observation made initially on clinical grounds and epidemiologic evidence, i.e., that rhinosinusitis and asthma are closely linked diseases is now supported by a growing body of scientific evidence. Most recent evidence supports the characterization of rhinosinusitis and asthma as two compartmental expressions of a common mucosal susceptibility to exogenous stimuli. In addition, there is evidence that the compartmental processes can affect and amplify each other via a systemic intermediary. The bone marrow is involved in this process, and IL-5 may be a key cytokine for orchestrating the systemic interaction. These facts argue that rhinosinusitis and asthma are not simply localized disease processes but part of a systemic inflammatory disease affecting the respiratory tract. They also provide a compelling rationale for combined treatment strategies with consideration of the treatment of rhinosinusitis as a means of improving asthma control and monitoring for signs of bronchial involvement in those with rhinosinusitis.

Cigarette smoke combined with Toll-like receptor 3 signaling triggers exaggerated epithelial regulated upon activation, normal T-cell expressed and secreted/CCL5 expression in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by persistent mucosal inflammation and frequent exacerbations.

OBJECTIVE

To determine whether innate epithelial responses to cigarette smoke or bacterial or viral pathogens may be abnormal in CRS leading to an inappropriate inflammatory response.

METHODS

Primary nasal epithelial cells (PNECs) were grown from middle turbinate biopsies of 9 healthy controls and 11 patients with CRS. After reaching 80% to 90% confluence, PNECs were exposed to medium or cigarette smoke extract (CSE) 5% (vol/vol) for 1 hour, washed, then stimulated with staphylococcal lipoteichoic acid, LPS, or double-stranded RNA (dsRNA). After 24 hours, gene expression was quantified by QRT-PCR.

RESULTS

At baseline, PNECs revealed elevated TNF-alpha and growth-related oncogene-alpha (a C-X-C chemokine)/CXCL1 (GRO-alpha) (4-fold increase, P = .02; and 16-fold increase, P = .004, respectively) in subjects with CRS compared with controls with normal levels of IL-1beta, IL-6, IL-8/CXCL8, human beta-defensin-2, monocyte chemoattractant protein 2/CCL8, monocyte chemoattractant protein 3/CCL7, and regulated upon activation, normal T-cell expressed and secreted (RANTES)/CCL5. Immunostaining of nasal biopsies, however, revealed comparable epithelial staining for TNF-alpha, GRO-alpha, and RANTES. There were no differences in mRNA induction by CSE, TNF-alpha, lipoteichoic acid, LPS, or dsRNA alone. The combination of CSE+dsRNA induced exaggerated RANTES (12,115-fold vs 1500-fold; P = .03) and human beta-defensin-2 (1120-fold vs 12.5-fold; P = .05) in subjects with CRS. No other genes were differentially induced. Furthermore, CSE+dsRNA induced normal levels of IFN-beta, IFN-lambda1, and IFN-lambda2/3 mRNA in subjects with CRS.

CONCLUSION

Cigarette smoke extract plus dsRNA induces exaggerated epithelial RANTES expression in patients with CRS. We propose that an analogous response to cigarette smoke plus viral infection may contribute to acute exacerbations and eosinophilic mucosal inflammation in CRS.

Long-term safety study of levalbuterol administered via metered-dose inhaler in patients with asthma

BACKGROUND

Previous studies have raised concerns regarding the safety of regular use of beta2-agonists for treating asthma. Few studies have explored the safety of at least 1 year of use of racemic albuterol, and none have examined long-term dosing of levalbuterol.

OBJECTIVE

To examine the long-term safety of levalbuterol hydrofluoroalkane (HFA) vs racemic albuterol HFA administered via metered-dose inhaler (MDI) in patients with stable asthma.

METHODS

Patients with mild to moderate asthma (mean forced expiratory volume in 1 second [FEVI], 68.3% of predicted) 12 years or older participated in a multicenter, parallel-group, open-label study. Patients were randomized to levalbuterol HFA MDI (90 microg; 2 actuations of 45 microg; n = 496) or racemic albuterol HFA MDI (180 microg; 2 actuations of 90 microg; n = 250) for 52 weeks of 4 times daily dosing. The primary end point was the incidence of postrandomization adverse events. Asthma exacerbations and pulmonary parameters were also assessed.

RESULTS

The overall incidence of adverse events was similar for levalbuterol (72.0%) and racemic albuterol (76.8%). Rates of beta-mediated adverse events, serious adverse events, and discontinuations because of adverse events were low (<15%) and were comparable between groups. Rates of asthma adverse events for levalbuterol and racemic albuterol were 18.3% and 19.6%, respectively. Mean percentage of predicted FEV1 improved after dosing and was stable for both groups.

CONCLUSION

In this trial, up to 52 weeks of regular use of levalbuterol HFA MDI or racemic albuterol HFA MDI was well tolerated, and no deterioration of lung function was detected during the study period.

Nasal and sinus endoscopy for medical management of resistant rhinosinusitis, including postsurgical patients

Nasal endoscopy has been practiced by allergists since the early 1980s; however, allergists in general have not embraced endoscopic evaluation of patients with sinus disease, either before or after surgery. Allergists are in a unique position to render medical (as opposed to surgical) care of patients with sinusitis. There has been a growing realization that endoscopy is a valuable procedure for the evaluation and medical treatment of patients with difficult sinusitis. This has resulted in the need for a resource to allow allergists to understand the nature of endoscopic findings in patients with sinusitis, either preoperatively or postoperatively. This article introduces the findings at endoscopy that are common in patients with sinusitis, including those that may be seen after surgery. The findings include perforation of the septum, retained secretions, small surgical ostium caused by postoperative ostial stenosis, previous Caldwell Luc procedure, recirculation of mucus, hyperplastic nasal disease, synechiae, recurrent disease in previously unaffected sinuses, empty nose syndrome, frontal sinus disease, dental disease, and other, more complicated entities.

WITHDRAWN: Endoscopic evaluation of resistant rhinosinusitis (before and after surgery) is now available on the American Academy of Allergy, Asthma & Immunology Web site

This article has been withdrawn consistent with Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). The Publisher apologizes for any inconvenience this may cause.

Rhinosinusitis: Developing guidance for clinical trials

The Rhinosinusitis Initiative was developed by 5 national societies. The current guidance document is an expansion of the 2004 publication, "Rhinosinusitis: Establishing definitions for clinical research and patient care" and provides templates for clinical trials in antimicrobial, anti-inflammatory, and symptom-relieving therapies for the following: (1) acute presumed bacterial rhinosinusitis, (2) chronic rhinosinusitis (CRS) without nasal polyps, (3) CRS with nasal polyps, and (4) classic allergic fungal rhinosinusitis. In addition to the templates for clinical trials and proposed study designs, the Rhinosinusitis Initiative has developed 6 appendices, which address (1) health outcomes, (2) nasal endoscopy and staging of CRS, (3) radiologic imaging, (4) microbiology, (5) laboratory measures, and (6) biostatistical methods.

Rhinosinusitis: developing guidance for clinical trials

The Rhinosinusitis Initiative was developed by 5 national societies. The current guidance document is an expansion of the 2004 publication "Rhinosinusitis: Establishing definitions for clinical research and patient care" and provides templates for clinical trials in antimicrobial, anti-inflammatory, and symptom-relieving therapies for the following: (1) acute presumed bacterial rhinosinusitis, (2) chronic rhinosinusitis (CRS) without nasal polyps, (3) CRS with nasal polyps, and (4) classic allergic fungal rhinosinusitis. In addition to the templates for clinical trials and proposed study designs, the Rhinosinusitis Initiative has developed 6 appendices, which address (1) health outcomes, (2) nasal endoscopy and staging of CRS, (3) radiologic imaging, (4) microbiology, (5) laboratory measures, and (6) biostatistical methods.

Ultrarush venom desensitization after systemic reactions during conventional venom immunotherapy

BACKGROUND

Rush and ultrarush venom immunotherapy (VIT) protocols are safe and effective in patients with Hymenoptera hypersensitivity. However, these protocols have typically been used instead of conventional VIT and not in patients who have experienced adverse reactions during conventional VIT. To date, there are no reports of using an ultrarush VIT protocol to desensitize patients with a history of severe systemic reactions during conventional VIT.

OBJECTIVE

To determine whether ultrarush VIT can be safely administered to a high-risk patient with a history of severe systemic reactions to conventional VIT.

METHODS

Premedication with 40 mg of prednisone, 180 mg of fexofenadine, and 150 mg of ranitidine orally twice daily was initiated. The patient received VIT to mixed vespid and wasp in a medical intensive care unit via a 13-step buildup on day 1 followed by a 2-step buildup on day 2. Immunotherapy was begun with a dose of 0.005 microg of mixed vespid and 0.002 microg of wasp venom and achieved a total dose of 300 microg of mixed vespid and 100 microg of wasp venom.

RESULTS

The patient tolerated the procedure with minimal adverse effects. She subsequently received maintenance dosing in the outpatient clinic weekly for 4 weeks and bimonthly for 8 weeks, and she continues monthly maintenance VIT.

CONCLUSIONS

We report the first successful use of ultrarush VIT in a high-risk patient with a history of severe systemic reactions during conventional VIT. This protocol should be considered in patients with a history of allergy to vespids or wasps who require VIT but cannot reach a maintenance dose with conventional VIT owing to systemic reactions.