Eosinophilic mucin rhinosinusitis: a distinct clinicopathological entity

Allergic fungal rhinosinusitis and eosinophilic mucin chronic rhinosinusitis: Differential diagnostic criteria. A two-center comparative study following STROBE methodology

OBJECTIVES

Allergic fungal rhinosinusitis (AFRS) and eosinophilic mucin chronic rhinosinusitis (EMRS) are two forms of chronic sinusitis distinguished by the presence (AFRS) or absence (EMRS) of fungal elements in sinus mucin. Detection of the fungal elements, however, is complex and it is difficult to say whether EMRS is in fact an entity distinct from AFRS. The aim of the present study, based on a retrospective series of AFRS and EMRS, was to identify the specific clinical and radiological elements distinguishing between the two.

MATERIALS AND METHODS

A 2-center retrospective observational study following STROBE guidelines included patients managed for AFRS or EMRS between 2009 and 2022. Clinical, mycological, pathologic and radiological data were collected. Type of treatment and disease progression were also analyzed. Intergroup comparison used Student's test for mean values of quantitative variables, with calculation of P-values, and Pearson's Chi2 test or Fisher's exact test for categoric variables, with calculation of relative risk and 95% confidence intervals.

RESULTS

The AFRS group comprised 41 patients and the EMRS group 34. Demographic data were comparable between groups. EMRS showed a higher rate of asthma (79.4 vs. 31.4%; P<0.001), more severe nasal symptomatology (rhinorrhea, P=0.01; nasal obstruction, P=0.001), and more frequent bilateral involvement (85.3 vs. 58.5%; P=0.021). AFRS showed more frequent complications (19 vs. 0%; P=0.006). Radiologically, mucin accumulation was greater in AFRS, filling the sinus in 84.2% of cases, versus 26.3% (P<0.001), with more frequent sinus wall erosion (19 vs. 5.8%; P=0.073). The recurrence rate was higher in EMRS: 38.2 vs.21.9% (P=0.087).

CONCLUSION

The present retrospective study found a difference in clinical and radiological presentation between AFRS and EMRS, with EMRS more resembling the presentation of severe nasal polyposis.

Allergic fungal rhinosinusitis: What we can learn from allergic bronchopulmonary mycosis

Allergic fungal rhinosinusitis (AFRS) and allergic bronchopulmonary mycosis (ABPM) are inflammatory disorders of the respiratory tract resulting from type 1 and 3 hypersensitivity reactions against fungi. The hallmark features of both diseases are eosinophil infiltration into the airway mucosa caused by localized type 2 inflammation and concomitant viscid secretions in the airways. Eosinophilic mucin-induced compression of adjacent anatomic structures leads to bone erosion and central bronchiectasis in the upper and lower respiratory tracts, respectively. Although these diseases share common features in their pathogenesis, they also exhibit notable differences. Epidemiologic findings are diverse, with AFRS typically presenting at a younger age, exhibiting less complicated bronchial asthma, and displaying lower total immunoglobulin E levels in laboratory findings compared with ABPM. Furthermore, despite their similar pathogenesis, the rarity of sinio-bronchial allergic mycosis in both AFRS and ABPM underscores the distinctions between these two diseases. This review aims to clarify the similarities and differences in the pathogenesis of AFRS and ABPM to determine what can be learned about AFRS from ABPM, where more is known.

Allergic Fungal Rhinosinusitis in Europe: Literature Review and Own Experience

Allergic fungal rhinosinusitis (AFRS) is primary, Th2-mediated, chronic rhinosinusitis, which is diagnosed when the criteria defined by Bent and Khun are met. The disease is most common in countries located in the subtropical and tropical regions characterized by high temperatures and high levels of humidity, which favour the wider occurrence of fungi in the environment. The presence of specific IgE antibodies directed against fungal allergens, which is one of the diagnostic criteria, proves the systemic nature of the disease and allows one to distinguish AFRS from eosinophilic fungal rhinosinusitis. There is no unified treatment method for AFRS described in the literature, and relapses are common. Sinus surgery remains the treatment of choice. Oral and topical steroid therapy plays an important role in the treatment process. The effectiveness of antifungal treatment and immunotherapy is unclear. Biological treatment, the results of which are promising, has raised great hopes. The aim of this study was to reveal how often AFRS occurs in European countries, what environmental factors influence its development, and how important it is to specify its diagnostic criteria and treatment methods. We present an overview of the available literature. In addition, we share our own experience and describe two cases of AFRS diagnosed and treated at our centre.

A review of current biomarkers in chronic rhinosinusitis with or without nasal polyps

INTRODUCTION

Chronic rhinosinusitis (CRS) is a heterogeneous disease with a variety of cellular and molecular pathophysiologic mechanisms. Biomarkers have been explored in CRS using various phenotypes, such as polyp recurrence after surgery. Recently, the presence of regiotype in CRS with nasal polyps (CRSwNP) and the introduction of biologics for the treatment of CRSwNP has indicated the importance of endotypes, and there is a need to elucidate endotype-based biomarkers.

AREAS COVERED

Biomarkers for eosinophilic CRS, nasal polyps, disease severity, and polyp recurrence have been identified. Additionally, endotypes are being identified for CRSwNP and CRS without nasal polyps using cluster analysis, an unsupervised learning technique.

EXPERT OPINION

Endotypes in CRS have still being established, and biomarkers capable of identifying endotypes of CRS are not yet clear. When identifying endotype-based biomarkers, it is necessary to first identify endotypes clarified by cluster analysis for outcomes. With the application of machine learning, the idea of predicting outcomes using a combination of multiple integrated biomarkers, rather than a single biomarker, will become mainstream.

Immunopathologic Role of Fungi in Chronic Rhinosinusitis

Airborne fungi are ubiquitous in the environment and are commonly associated with airway inflammatory diseases. The innate immune defense system eliminates most inhaled fungi. However, some influence the development of chronic rhinosinusitis. Fungal CRS is thought of as not a common disease, and its incidence increases over time. Fungi are present in CRS patients and in healthy sinonasal mucosa. Although the immunological mechanisms have not been entirely explained, CRS patients may exhibit different immune responses than healthy people against airborne fungi. Fungi can induce Th1 and Th2 immune responses. In CRS, Th2-related immune responses against fungi are associated with pattern recognition receptors in nasal epithelial cells, the production of inflammatory cytokines and chemokines from nasal epithelial cells, and interaction with innate type 2 cells, lymphocytes, and inflammatory cells. Fungi also interact with neutrophils and eosinophils and induce neutrophil extracellular traps (NETs) and eosinophil extracellular traps (EETs). NETs and EETs are associated with antifungal properties and aggravation of chronic inflammation in CRS by releasing intracellular granule proteins. Fungal and bacterial biofilms are commonly found in CRS and may support chronic and recalcitrant CRS infection. The fungal-bacterial interaction in the sinonasal mucosa could affect the survival and virulence of fungi and bacteria and host immune responses. The interaction between the mycobiome and microbiome may also influence the host immune response, impacting local inflammation and chronicity. Although the exact immunopathologic role of fungi in the pathogenesis of CRS is not completely understood, they contribute to the development of sinonasal inflammatory responses in CRS.

Current Insight into Treatment of Chronic Rhinosinusitis: Phenotypes, Endotypes and Implications for Targeted Therapeutics

Chronic rhinosinusitis (CRS) is characterized by persistent locoregional mucosal inflammation of the paranasal sinuses and upper airway that has substantial associated health care costs¹. Personalized approaches to care that incorporate use of molecular biomarkers, phenotypes and inflammatory endotypes is a major focus of research at this time, and the concurrent rise of targeted therapeutics and biologic therapies has the potential to rapidly advance care and improve outcomes. Recent findings suggest that improved understanding of CRS phenotypic and endotypic heterogeneity, and incorporation of these characteristics into clinical care pathways, may facilitate more effective selection of surgical and/or therapeutic interventions². Ultimately, these personalized approaches have the potential to target specific inflammatory pathways, increase efficacy, reduce costs, and limit side effects. This review summarizes recent advances in the identification and characterization of CRS phenotypes, endotypes, and biomarkers and reviews potential implications for targeted therapeutics.

Dupilumab: An emerging therapy in allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a highly resistant disease and is challenging to treat. Patients with recurrent attacks of the disease despite surgical management can benefit from biologics as adjunct therapies. Dupilumab has shown promising endpoints in patients with chronic rhinosinusitis with nasal polyposis (CRSwNP). This case series reports 4 patients with resistant AFRS concomitant with asthma, for which dupilumab therapy was administered. Long-term follow-ups showed that dupilumab improved the symptoms and improved the results of objective tools such as imaging and pulmonary function test.

The role of fungus in the pathogenesis of chronic rhinosinusitis

PURPOSE OF REVIEW

The etiologic role of fungi in chronic rhinosinusitis remains controversial. The purpose of this review is to further our understanding of molecular immunologic pathways activated by fungi and clinical trials of antifungals in severe subtypes of asthma and allergic fungal rhinosinusitis.

RECENT FINDINGS

Various fungal components such as protease and chitin are capable of eliciting a type 2 innate and adaptive immune response. However, definitive studies on the etiologic role of fungi in chronic rhinosinusitis (CRS) is dependent on the development of a fungi-induced murine model of CRS. Short of this model, extrapolations of observations and results from clinical trials in fungi-induced asthma subtypes support a key role of fungi in the pathophysiology of allergic fungal rhinosinusitis and possibly other CRS endotypes.

SUMMARY

Fungi plays a key role in the pathophysiology of several subtypes of chronic inflammatory respiratory diseases. However, a fungi-induced murine model of CRS is needed to explicitly investigate the molecular pathways and potential therapeutic targets.

Precision Medicine in Chronic Rhinosinusitis: Where Does Allergy Fit In?

Chronic rhinosinusitis (CRS) is a clinical syndrome stemming from persistent inflammation of the sinonasal mucosa. Phenotypically, it is traditionally and widely described according to the presence or absence of polyps. While this distinction is simple to use, it has little bearing on prognosis and treatment, for CRS is essentially an inflammatory disease resulting from dysregulated interaction between a multitude of host and environmental factors. Allergy is merely one of them and, like many of the proposed aetiologies, has been subject to much debate which will be discussed here. As our understanding of CRS continues to evolve, previous so-called conventional wisdom about phenotypes (e.g. CRS with nasal polyps is associated with Type 2 inflammation) is being challenged, and new phenotypes are also emerging. In addition, there is growing interest in defining the endotypes of CRS to deliver precise and personalised treatment, especially pertaining to the development of biologics for the group of severe, difficult-to-treat CRS patients. A proposed model of precision medicine tailored to management of CRS will also be introduced to readers, which can be continually modified to adapt to new discoveries about this exciting condition.

Allergic Fungal Rhinosinusitis in Saudi Arabia: A Review of Recent Literature

Allergic fungal rhinosinusitis (AFRS) has been considered an enigma since it was first described four decades ago. Previous research has found that AFRS has multiple definitions and a poorly understood pathogenesis because it overlaps with other conditions and necessitates meticulous work and multiple diagnostic modalities to confirm the diagnosis. However, despite the expansion of medical and surgical treatments, recurrence still occurs. In this review, the recent literature on AFRS cases in Saudi Arabia with relevance to its epidemiology, diagnosis, and management was studied and compared with international data. PubMed, Google Scholar, and Cochrane Library were searched for original research and review articles with local data. There is an evident paucity and contradiction between local studies regarding the epidemiology, diagnostic methods, and management of AFRS. Hence, well-defined randomized controlled trials (RCTs) are needed for the treatment of this chronic recurrent disease.

Eosinophil extracellular traps in a patient with chronic eosinophilic pneumonia

Eosinophils rapidly release extracellular filamentous chromatin fibers (extracellular traps, ETs) when they are stimulated. Reticulated ETs have been recently shown to affect secretion viscosity in eosinophilic inflammatory diseases. Here we report a 43-year-old woman with infiltrative shadows in both upper lungs that did not respond well to antibiotics. She admitted to occasional coughing and sputum, but had poor viscous regulation. Bronchoalveolar lavage fluid (BALF) collected from the upper left lobe showed many eosinophils (65%). She was diagnosed with chronic eosinophilic pneumonia, per previously reported criteria, and began treatment with prednisolone. The infiltration shadow gradually improved, and she was discharged 28 days after admission. Later, we immune-stained her BALF cell components with antibodies against major basic protein, an eosinophil granule protein, which showed a large number of agglomerating eosinophils; and antibodies against citrullinated histone H3 (CitH3-a marker for ETs), which showed CitH3-positive ETs, spread in a network. These findings confirmed that some BALF eosinophils released eosinophil ETs. This case shows the existence of ETs from BALF in patients with chronic eosinophilic pneumonia. Concentration of eosinophil ETs in eosinophilic inflammatory diseases may affect secretion viscosity in sputum, and so on.

Phenotypes of Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a complex heterogeneous disease with different phenotypes and endotypes. Recent advances in our understanding of the pathogenetic mechanisms of CRS endotypes have led to the introduction of effective biologic agents for CRS management. Traditionally, CRS phenotypes have been divided into with or without nasal polyps depending on the presence of polyps. Although this classification does not reflect the various endotypes that are recently emerging, it is simple and easily recognized by clinicians. Other phenotypes of CRS are fungal rhinosinusitis (including invasive and noninvasive subtypes), infectious rhinosinusitis, aspirin-exacerbated respiratory disease, cystic fibrosis, pediatric CRS, and CRS associated with systemic diseases. This article reviews the diagnostic approaches and up-to-date treatment strategies for each CRS phenotype with the hope that a better understanding of endotypes will result in a more scientific understanding of phenotypes and precise, personalized treatments.

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.

Eosinophilic Mucin: A Predictor for Disease Severity in Chronic Rhinosinusitis

OBJECTIVE

The presence of tissue eosinophilia is a determinate of disease severity in patients with chronic rhinosinusitis (CRS). The impact of eosinophilic mucin (EM) as an independent variable has not yet been elucidated.

STUDY DESIGN

Retrospective review.

SETTING

Tertiary academic clinic.Subjects Methods: CRS patients who failed medical therapy were classified by tissue eosinophilia, presence of polyps and EM. Tissue eosinophilia count per high power field (HPF) as well as the presence of EM were determined by pathologic examination of sinus tissue removed during surgery. Sinonasal Outcomes Test (SNOT-22), Lund-Mackay (LM), and Lund-Kennedy (LK) scores were compared between all groups preoperatively and postoperatively up to two and a half years (30 months).

RESULTS

192 patients with CRS were included in the study. 87 were diagnosed with eosinophilic CRS with polyps, 58 with eosinophilic CRS without polyps, 14 with noneosinophilic CRS with polyps, and 33 with noneosinophilic CRS without polyps. Only patients with eosinophilia had EM on pathology. Of eosinophilic CRS, 50% of patients with polyps and 12% of cases without polyps demonstrated EM, respectively. EM presence portended more severe disease in patients with eosinophilia on subjective and objective scores preoperatively (P < 0.005). Postoperatively, EM patients experienced a greater improvement of symptoms, but continued to have worse endoscopy scores until 1.5 years. A tissue eosinophil count of 30 or greater per HPF was identified as a potential marker for the development of EM.

CONCLUSIONS

The presence of eosinophilic mucin predicts overall worse disease severity in patients with eosinophilic CRS.

Clinical, Radiological, and Histopathological Patterns of Allergic Fungal Sinusitis: A Single-Center Retrospective Study

Objectives

To explore the clinical, pathological, and imaging characteristics of allergic fungal sinusitis (AFS) and to analyze the correlation of disease duration with imaging and histopathology findings.

Methods

We reviewed all cases of AFS managed at the otorhinolaryngology department of King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia. Demographic and clinical features were collected, as well as imaging and histopathological findings, which were analyzed by time from onset.

Results

Forty-six patients were diagnosed AFS, representing 11.8% of total sinusitis cases; 25 (54.3%) were female, with mean (SD) age=33.57 (11.76). Patients presented with multiple symptoms of chronic rhinosinusitis (43, 93.5%), chronic headache (14, 30.4%), and hyposmia (2, 4.3%), and 36 (78.3%) were diagnosed late (≥5 years after onset). AFS involved all four sinuses in 32 (69.6%) patients and was bilateral in >53.5% of infected sinuses. Imaging showed increased intrasinus attenuation (88.2%-95.3%), complete opacification (74.4%-85.3%), sinus expansion (35.3%-51.2%), remodeling (20.6%-37.2%), wall thinning (41.2%-58.1%), and involvement of adjacent soft tissue (11.8%-25.6%), depending on the sinus type. Histology evidenced eosinophilic mucin (45.7%), eosinophils (91.3%), fungal hyphae (93.5%), and Charcot-Leyden crystals (6.5%). Patients who were diagnosed late had a higher percentage of imaging and pathological lesions, principally, the expansion and wall thinning of involved sinuses (p<0.050).

Conclusion

AFS represents a significant proportion of chronic sinusitis cases treated in the otorhinolaryngology department and is often diagnosed late with extensive forms. Major efforts should be made to improve the early diagnosis and management of such disease, including raising awareness about this entity among general practitioners and family physicians to enhance clinical suspicion and detection rate.

Fungal Rhinosinusitis: Prevalence and Spectrum in Singapore

Background

Fungal involvement of the paranasal sinuses has been described more than two centuries ago. In the current article, it is referred to as fungal rhinosinusitis (FRS) which is a general term that is used to describe a spectrum of pathologically, immunologically, and clinically different disease entities affecting the paranasal sinuses where fungus is thought to be the major potential etiology.

Objective

To determine the incidence and spectrum of FRS in Singapore and to compare our findings with international figures through literature review.

Methods

A retrospective review of the clinical charts, radiological and laboratory results, and operative reports of all patients who underwent endoscopic sinus surgery at an ENT department of a tertiary referral hospital in Singapore over five-year period.

Results

Out of 533 functional endoscopic sinus surgeries performed during the period of the study for management of chronic rhinosinusitis, 44 (8.4%) were found to fit the criteria for diagnosis of FRS. Twenty (45.5%) were eosinophilic FRS and 24 (54.5%) were fungal balls. Invasive FRS has not been encountered. Clinical presentation, investigations, and management of both groups of patients are discussed.

Conclusion

Fungal rhinosinusitis is not uncommon in Singapore. Fungal ball and eosinophilic mucin fungal rhinosinusitis are among the most common forms encountered in this part of the world.

Two Cases of Allergic Fungal Sinusitis with Differing Postoperative Course

Allergic fungal sinusitis (AFS) often develops in unilateral paranasal sinuses, which must be differentiated from tumors. When AFS develops on both sides, however, it must be differentiated from eosinophilic chronic sinusitis with evident eosinophilic infiltration at nasal/paranasal sinus mucosa; both conditions are highly recurrent and commonly considered intractable paranasal sinusitis. Surgical correction is the primary treatment method for AFS, as it is essential to connect the paranasal sinus communication to ensure exhaustive resection of the pathologic mucosa and for nasal steroids to reach each paranasal sinus. We recently encountered two AFS cases with differing postoperative courses. Case 1 showed evident exacerbation in the computed tomography findings, which suggests progression to eosinophilic sinusitis. Case 2 showed a benign prognosis without recurrence. Close long-term follow-up should be mandatory after surgery for the treatment of AFS.

Allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a subset of chronic rhinosinusitis with nasal polyps (CRSwNP) characterized by antifungal IgE sensitivity, eosinophil-rich mucus (ie, allergic mucin), and characteristic computed tomographic and magnetic resonance imaging findings in paranasal sinuses. AFRS develops in immunocompetent patients, with occurrence influenced by climate, geography, and several identified host factors. Molecular pathways and immune responses driving AFRS are still being delineated, but prominent adaptive and more recently recognized innate type 2 immune responses are important, many similar to those established in patients with other forms of CRSwNP. It is unclear whether AFRS represents merely a more extreme expression of pathways important in patients with CRSwNP or whether there are other disordered immune responses that would define a distinct endotype or endotypes. Although AFRS and allergic bronchopulmonary aspergillosis share some analogous immune mechanisms, the 2 conditions do not occur commonly in the same patient. Treatment of AFRS almost always requires surgical debridement of the involved sinuses. Oral corticosteroids decrease recurrence after surgery, but other adjunctive pharmacologic agents, including topical and oral antifungal agents, do not have a firm evidence basis for use. There is good rationale for use of biologic agents that target eosinophilic inflammation or other type 2 responses, but studies in patients with AFRS are required.

The use of magnetic resonance imaging in differential diagnosis of allergic fungal sinusitis and eosinophilic mucin rhinosinusitis

Background

Allergic fungal sinusitis (AFS) and eosinophilic mucin rhinosinusitis (EMRS) represent pathophysiological variants of sinusitis and have similar clinical features. However, to date, few studies have described the differential diagnosis of AFS and EMRS in detail. We therefore investigated the use of magnetic resonance imaging (MRI) in the differential diagnosis of AFS and EMRS.

Methods

Ninety-three patients (aged 13-75 years) with sinusitis and AFS or EMRS established according to pathological, clinical, or laboratory examinations were enrolled. Each patient was evaluated for demographic and clinical characteristics, fungal-specific immunoglobulin E, peripheral blood eosinophils, histopathology of the sinuses, as well as signal attenuation within the opacified sinuses on computed tomography and MRI scans.

Results

Thirty patients presented with AFS and 63 with EMRS. The histopathological characteristics of the secretion and mucosa in the affected sinuses, but not the absolute counts or percentage of blood eosinophils, differed between the 2 groups. The presence of asthma was significantly higher in the EMRS group, whereas allergy to fungi and T2-weighted MRI signal attenuation were significantly increased in the AFS group.

Conclusions

MRI features are key to the differential diagnosis of AFS and EMRS.

Clinical assessment, diagnosis and management of patients with unilateral sinonasal disease

OBJECTIVES

Unilateral sinonasal disease is commonly encountered in practice and represents an issue of major concern since neoplasms may mimic inflammatory conditions. This paper aims to describe the demographic, clinical and radiological patterns of unilateral pathologies and, accordingly, to establish a guiding algorithm for diagnosis and management.

MATERIAL AND METHODS

We conducted a retrospective review of medical records of patients with unilateral sinus opacification on CT scan who underwent endoscopic nasal surgery in our department from January 2011 to December 2017.

RESULTS

Of the 150 patients included, 97(64.7%) and 53(35.3%) had inflammatory and neoplastic pathology, respectively. In the neoplastic group, malignancy was present in 35% of patients. Neoplastic conditions were more common in males (p=0.02) and older patients (56±18 years vs. 38±18, p<.01). Nasal mass or polyp was observed in 56.7% patients. Chronic sinusitis was the most prevalent inflammatory condition, whereas inverted papilloma and osteoma were the most frequent neoplasms. Facial neuralgia, paraesthesia, epistaxis and, on CT scan, superior Lund-Mackay scores, bone remodelling and erosion were significantly more common in neoplastic conditions. Excellent agreement between punch biopsy and postoperative histological results was obtained (k=.883, p<.001).

CONCLUSION

A sequential and careful management of unilateral lesions is mandatory. Based on our experience, we propose that, as routine, physical examination should be complemented with nasal endoscopy, CT scan and punch biopsy, in case of visible mass. Although clinical and radiological information might raise suspicion of some conditions, final diagnosis can only be established with histological examination of the surgical specimen.

Fungal Rhinosinusitis: Unravelling the Disease Spectrum

Fungal rhinosinusitis (FRS), once considered a rare disease, has seen a steep rise in incidence in recent times. This global rise in the burden of fungal disease is a consequence of an increment in the population with weakened immune systems. Increased life expectancy with rise in conditions like diabetes mellitus, medical advancements with invasive interventions, use of immunosuppressive drugs and chemo-radiotherapy all lead to unique risk situations. The situation becomes more alarming with the fact that there has been a significant rise in cases in immune-competent hosts with no predisposing factors. FRS represents a wide spectrum of disease ranging from the mild form of superficial colonization, allergic manifestations to life threatening extensive invasive disease. The categorization of disease into acute and chronic and invasive or noninvasive is important factor with implications in disease management and prognosis and this has been emphasized greatly in recent years. Diagnosis of FRS has been a challenge as the presenting clinical signs and symptoms and radiographic manifestations are often nonspecific. Definitive diagnosis requires direct fungi identification and hence culture and microscopic examination remain the gold standard. Availability of advanced and rapid diagnostic techniques is rare in majority of developing nations. Therapeutic dilemmas are another aspect of the management of FRS as in spite of the availability of new antifungal drugs, treatment is often empirical due to non-availability of early diagnosis, rapid disease progression and high costs of antifungal drugs. A description of the different types of FRS, their diagnosis and management has been presented in this review.

Serum Cytokine Profile in Patients with Chronic Rhinosinusitis with Nasal Polyposis Infected by Aspergillus flavus

Background

Fungi, especially Aspergillus flavus, can cause chronic rhinosinusitis with nasal polyposis and modulate host innate immune components. The objective of this study was to examine the serum levels of T helper (Th) cell subset Th1, Th2, and Th17 cytokines and total IgE in patients having chronic rhinosinusitis with nasal polyposis and Aspergillus flavus infection.

Methods

A case-control study including 40 patients with chronic rhinosinusitis with nasal polyposis and 20 healthy controls was conducted. Aspergillus flavus infection was confirmed by standard potassium hydroxide (KOH) testing, culture, and PCR. Serum samples of all patients and controls were analyzed for various cytokines (interleukins [IL]-1β, IL-2, IL-4, IL-6, IL-17, IL-21, IL-27, TGF-β) and total IgE by ELISA. Data from patients with Aspergillus flavus infection and healthy volunteers were compared using the independent t-test and non-parametric Mann-Whitney U test.

Results

Aspergillus flavus infection was found in 31 (77.5%) patients with chronic rhinosinusitis with nasal polyposis. IL-1β, IL-17, IL-21, and TGF-β serum levels were significantly higher in these patients than in controls; however, IL-2, IL-4, IL-6, and IL-27 levels were lower. Compared with nine (22.5%) patients without Aspergillus flavus infection, IL-17 level was higher while IL-2 level was lower in patients with Aspergillus flavus infection. Total IgE was significantly higher in patients with Aspergillus flavus infection than in controls.

Conclusions

High levels of IL-17 and its regulatory cytokines in patients with chronic rhinosinusitis with nasal polyposis infected by Aspergillus flavus raise a concern about effective disease management and therapeutic recovery. Surgical removal of the nasal polyp being the chief management option, the choice of post-operative drugs may differ in eosinophilic vs. non-eosinophilic nasal polyposis. The prognosis is likely poor, warranting extended care.

Th2 Immunological Inflammation in Allergic Fungal Sinusitis, Nonallergic Eosinophilic Fungal Sinusitis, and Chronic Rhinosinusitis

Background

Noninvasive fungal sinusitis is a heterogenous group of conditions including allergic fungal sinusitis (AFS) and nonallergic eosinophilic fungal sinusitis (NEFS). Th2-mediated cascades have been postulated to be the major inflammatory response in patients with AFS although other mechanisms also may be involved. The detailed mucosal Th2 cytological status of NEFS still has not been studied in great depth.

Methods

Using a meticulous patient selection algorithm over a 2-year period, infundibular mucosal tissue from patients with AFS, NEFS, chronic rhinosinusitis (CRS), and normal controls was studied (n = 59). Immunohistochemistry for mast cells, eosinophils, and immunoglobulin E (IgE) cells was performed and cell counts per unit area were measured.

Results

Mast cell, eosinophil, and IgE+ cell numbers were significantly raised in patients with AFS, NEFS, and CRS when compared with controls. There was no significant difference between cell numbers in patients with AFS and NEFS.

Conclusion

Patients with AFS exhibit a classic Th2 inflammatory response in nasal mucosal tissue with NEFS and CRS patients showing evidence of a similar Th2 cascade, including the presence of IgE+ cells.

Chronic Sinusitis with Nasal Polyps: Staphylococcal Exotoxin Immunoglobulin E and Cellular Inflammation

Background

The etiology of chronic sinusitis with nasal polyposis (CS/NP) remains enigmatic. Frequently, Staphylococcus aureus is present in the nose of CS/NP patients, although the significance is unclear. Recent reports have suggested the hypothesis that these bacteria may secrete exotoxins triggering the inflammatory mucosal changes seen in CS/NP. This mechanism of immunopathology has been established in other diseases associated with Staphylococcus colonization and exotoxin secretion such as atopic dermatitis. In atopic dermatitis, the exotoxins incite a local superantigen response in which clonal T-cell activation and massive cytokine release occur in the affected skin. Second, these exotoxins can act as traditional allergens, stimulating a typical immunoglobulin E (IgE) response in the serum, which has been correlated with disease severity. This study is designed to begin the assessment of the hypothesis that a similar mechanism takes place in CS/NP.

Methods

Serum was drawn from patients with CS/NP undergoing endoscopic sinus surgery as well as 13 atopic and nonatopic control subjects without sinusitis. IgE levels to S. aureus exotoxins A (SEA), SE exotoxins B (SEB), and toxic shock syndrome toxin 1 were measured using enzyme-linked immunosorbent assay. Tissue eosinophilia and the presence of lymphocytes on hemotoxylin and eosin-stained sections of polyps were scored by a blinded pathologist and correlated to presence of toxin IgE in the serum.

Results

Staphylococcal exotoxin (SE)-specific IgE was found in the serum of 5/10 (50%) of the patients with CS/NP. In contrast, 0/13 control patients had IgE to the exotoxins (p = 0.031). Polyp eosinophil, lymphocyte, and mononuclear cell counts were compared in IgE exotoxin-positive and -negative subjects. A trend toward increased eosinophil counts in patients with SE IgE (SE IgE+) was present, but not statistically significant.

Conclusion

These results indicate that a high percentage of CS/NP patients show a systemic IgE response to S. aureus exotoxins in comparison with controls without CS/NP. Although these results are consistent with the actions of Staphylococcus toxins in other diseases, additional work is necessary to establish a local superantigen response in the nasal mucosa of CS/NP patients. (American Journal of Rhinology 18, 273–278, 2004)

Prevalence of Noninvasive Fungal Sinusitis in South Australia

Background

The aim of this study was to document the prevalence of noninvasive fungal sinusitis in patients with chronic sinusitis and thick viscous secretions in South Australia.

Methods

We studied of 349 patients with chronic rhinosinusitis undergoing endoscopic sinus surgery in a specialized rhinology practice. Patients with nasal polyposis and thick fungal-like sinus mucin had operative samples sent for microscopy and fungal culture. Evidence of atopy was taken as positive radioallergosorbent or skin-prick tests to fungi.

Results

One hundred and thirty-four (38%) patients were noted to have thick, viscid sinus mucin, raising suspicion of fungal disease. Ninety-three patients had positive fungal cultures or microscopy (26.6%). It was possible to classify 95.5% of the patients into subgroups of noninvasive fungal sinusitis or nonfungal sinusitis: 8.6% of patients with allergic fungal sinusitis, 1.7% of patients with allergic fungal sinusitis–like sinusitis, 15.2% of patients with chronic fungal sinusitis, one patient with a fungal ball, and the remaining 69% of patients with nonfungal chronic sinusitis.

Conclusion

This is the first prospective study to evaluate the prevalence of these increasingly widely recognized conditions. It highlights the need for otolaryngologists to be alert to these not uncommon diagnoses in order for early, appropriate medical and surgical management to be instituted.

Histopathological Features of Nasal Polyps with Asthma Association: An Immunohistochemical Study

Background

Myofibroblasts are related to airway remodeling and may play an important role in the pathogenesis of the histological features of nasal polyps associated with asthma. The aim of this study was to analyze and compare the eosinophilic cationic protein, transforming growth factor (TGF) β, and myofibroblasts in the nasal polyps of patients with chronic sinusitis associated with and without asthma.

Methods

Nasal polyp samples were obtained during endoscopic sinus surgery and were classified into asthma and nonasthma groups. Immunohistochemistry was performed using antibodies against activated eosinophils, TGF-β, and myofibroblasts.

Results

The asthma group showed an increased number of activated eosinophils, TGF-β, and myofibroblasts compared with the nonasthma and control groups. We found no correlation of asthma and aspirin intolerance with the immunohistochemical findings.

Conclusion

The increased number of myofibroblasts in the nasal polyps of the asthma group may be responsible for the extracellular matrix accumulation, polyp formation, and polyp recurrence.

Treatment of Allergic Fungal Sinusitis with High-Dose Itraconazole

Background

Since its original description in the early 1980s, our understanding of allergic fungal sinusitis (AFS) has continued to evolve. The goal of this research was to characterize the typical AFS patient and describe a treatment protocol using endoscopic sinus surgery, high-dose itraconazole, low-dose bursts of oral corticosteroids, and topical corticosteroids.

Methods

A 12-year retrospective chart review was conducted to extract demographic and management data on 139 patients meeting the AFS criteria of atopy, characteristic radiographic findings, eosinophilic mucin, nasal polyposis, and a positive fungal culture or stain.

Results

The typical AFS patient presented at 42.8 years of age, was female, and had 3.5 positive fungal cultures over an average of 31.4 months of follow-up. Although 69 patients (50.3%) experienced recurrence, reoperation was required in only 17 (20.5%) of 83 patients initially managed by our protocol. There were no serious adverse effects attributed to itraconazole over the 36,000 doses prescribed.

Conclusion

The use of itraconazole, short-burst low-dose oral corticosteroids, topical corticosteroids, and endoscopic surgery is a safe and clinically effective regimen in the management of AFS. Our clinical experience suggests medical management of recurrent AFS with itraconazole may avoid revision surgery.

Nasal Mycology of Chronic Rhinosinusitis

Background

Ponikau used a novel collection and culturing method to recover fungi from nasal secretion in patients with chronic rhinosinusitis. The same method had been used previously in Europe with a similar result. However, the use of Ponikau's method has not been reported in Asia.

Methods

Fifty-one patients with chronic rhinosinusitis who were scheduled for functional endoscopic sinus surgery were enrolled in this study. One day before functional endoscopic sinus surgery, swab specimens were obtained from middle meatuses and were sent to the microbiology laboratory for routine bacterial and fungal cultures. Then, the same nasal cavity was lavaged with 20 mL of sterile water. The exhaled fluid was collected and processed using the Ponikau method. Skin testing with Candida extract was done also in all patients. The results obtained by different culture methods were compared.

Results

Bacteria grew from 45 of 51 swab specimens. The culture rate was 88.2%. Fungi were cultured from 6 of 51 swab specimens (11.8%) and from 25 of 51 lavage specimens (49%). The fungal culture rates were significantly different between swab and lavage specimens (p < 0.001). Candida was the most common cultured fungi in the lavaged specimens.

Conclusions

The study showed that Ponikau's method resulted in a higher fungal culture rate than that obtained with the swab method, but the culture rate was lower than the bacterial culture rate. Additional study is needed to investigate the role of fungi in the pathogenesis of chronic rhinosinusitis.

Otitis media with effusion and atopy: is there a causal relationship?

Otitis Media with Effusion (OME) is an inflammatory condition of the middle ear cleft, acute or chronic, with collection of fluid in the middle ear with an intact tympanic membrane. It is a very common disease in childhood, the most frequent cause of hearing loss in childhood and often requiring surgery. OME is called chronic when the fluid in the middle ear persists for more than three months or when the episodes recur six or more times in one year. The current article covers various aspects of OME including definition, epidemiology. Pathomechanisms, risk factors, role of allergy in OME, impact of upper airway disease on OME, eosinophilic otitis media and management of OME.

Contemporary Pharmacotherapy for Allergic Rhinitis and Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) and allergic rhinitis (AR) are chronic conditions causing nasal inflammation. CRS is increasingly recognized as a chronic inflammatory process rather than a chronic infection. Although the primary initiating factors in CRS remain unclear, AR is driven by IgE-mediated hypersensitivity to environmental allergens. Understanding the underlying inflammatory pathways and disease endotypes are driving innovation toward novel pharmacotherapies targeting critical mediators implicated in CRS and AR, including IL-4, IL-13, IL-5, IgE, and epithelial initiators IL-33 and TSLP. Extensive investigations are needed to determine the role, timing, predictive prognostic factors and long-term safety and efficacy of these agents.

Eosinophil ETosis and DNA Traps: a New Look at Eosinophilic Inflammation

The traditional paradigm of eosinophils as end-stage damaging cells has mainly relied on their release of cytotoxic proteins. Cytokine-induced cell survival and secretion of granular contents from tissue-dwelling eosinophil are thought to be important mechanisms for eosinophilic inflammatory disorders, although the occurrence of cytolysis and its products (i.e., free extracellular granules) has been observed in affected lesions. Recent evidence indicates that activated eosinophils can exhibit a non-apoptotic cell death pathway, namely extracellular trap cell death (ETosis) that mediates the eosinophil cytolytic degranulation. Here, we discuss the current concept of eosinophil ETosis which provides a new look at eosinophilic inflammation. Lessons from eosinophilic chronic rhinosinusitis revealed that ETosis-derived DNA traps, composed of stable web-like chromatin, contribute to the properties of highly viscous eosinophilic mucin and impairments in its clearance. Intact granules entrapped in DNA traps are causing long-lasting inflammation but also might have immunoregulatory roles. Eosinophils possess a way to have post-postmortem impacts on innate immunity, local immune response, sterile inflammation, and tissue damage.

Maintenance of pathogenic Th2 cells in allergic disorders

Immunological memory is an important protective mechanism that enables host organisms to respond rapidly and vigorously to pathogens that have been previously encountered. In addition to the protective function, memory CD4⁺ T helper (Th) cells play a central role in the pathogenesis of chronic inflammatory disorders, including asthma. Recently, several investigators have identified phenotypically and functionally distinct memory Th2 cell subsets that produce IL-5. These memory Th2 cell subsets play an important role in the pathology of allergic inflammation and function as memory-type "pathogenic Th2 (Tpath2) cells" both in mice and humans. We review the role of lung Tpath2 cells in the development of allergic inflammation and, in the context of recent findings, propose a mechanism by which Tpath2 cells not only survive but also continue to function at the sites where antigens were encountered. A greater understanding of the functional molecules or signaling pathways that regulate the inflammatory niche for Tpath2 cells may aid in the design of more effective treatments for chronic inflammatory disorders.

Delayed type of allergic skin reaction to Candida albicans in eosinophilic rhinosinusitis cases

OBJECTIVE

Eosinophilic chronic rhinosinusitis (ECRS) is frequently complicated by asthma, and recognized as refractory and persistent rhinosinusitis. However, the detailed pathophysiology of ECRS has not been elucidated yet. In this study, we investigated the association between recurrent ECRS and intradermal testing to multi-antigens including Candida albicans.

METHODS

The subjects were 49 cases of bilateral chronic rhinosinusitis including 24 ECRS cases. They underwent endoscopic sinus surgery and submitted to pathological examination. Prior to surgery, peripheral blood eosinophil count, total and antigen-specific IgE levels (11 categories), and intradermal tests (5 categories) were carried out in all patients. These patients were followed-up for longer than 3 months. We compared the results of preoperative and postoperative clinical examination data between ECRS and non-ECRS (NECRS) cases.

RESULTS

Positive reaction of the delayed type of intradermal testing to C. albicans was significantly more often observed in ECRS than NECRS cases. (P<0.01) Additionally, these positive reaction cases exhibited significantly higher recurrence of nasal polyps and symptoms of ECRS (P<0.05).

CONCLUSION

These results suggest the involvement of (Coombs) type IV allergic reaction to C. albicans in the pathophysiology of ECRS.

Literature review. Noninvasive fungal rhinosinusitis

Fungus ball (FB) of the paranasal sinuses has a distinctive clinicopathological presentation. The disease occurs more frequently in elderly patients and has a female preponderance. Classically, it involves only one paranasal sinus in more than 90% of the cases, most commonly the maxillary sinus. Imaging characteristics (calcifications and / or erosion of the inner wall of the sinus visible on CT) and histopathological ones (luminal aggregation of fungal hyphae) confirm the diagnosis.

Allergic fungal rhinosinusitis (AFRS) usually occurs in younger, immunocompetent patients, with a history of atopy, including allergic rhinitis and / or asthma, or a long clinical picture of chronic rhinosinusitis (CRS), refractory to antibiotic treatment. Nasal polyps (NP) are present in almost all patients, while extra-sinusal complications are described only in some of them. Usually, there is involvement of several sinuses, as well as bilateral damage. The definitive diagnosis is confirmed only by examining surgical specimens - the characteristic appearance of eosinophilic mucin is the most reliable indicator of AFRS.

Monoclonal Antibodies for the Treatment of Nasal Polyps

Biologics are novel therapeutic medications developed for the targeted therapy for a variety of inflammatory conditions. The biologics currently investigated for the treatment of chronic rhinosinusitis (CRS) with nasal polyps modulate specific inflammatory pathways involved in the pathogenesis of disease. Investigations have focused on the most severe form of the disease, namely, CRS with nasal polyps. It is hoped that specific targeted therapies using these biologics can significantly modulate the immune system, offering both disease control and symptomatic relief. This review summarizes those therapies that have been used to treat nasal polyps.

Inflammatory and Infectious Lesions of the Sinonasal Tract

The sinonasal tract is frequently affected by nonneoplastic inflammatory diseases. Inflammatory lesions of the sinonasal tract can be divided into 3 main categories: chronic rhinosinusitis, which encompasses a heterogeneous group of entities, all of which result in mucosal inflammation with or without polyps-eosinophils; infectious diseases; and autoimmune diseases and vasculitides, which can result in midline necrosis and facial deformities. This article reviews the common inflammatory lesions of the sinonasal tract with emphasis on infectious diseases, vasculitis, iatrogenic, and diseases of unknown cause. Many of these lesions can result in midline destruction and result in facial deformity.

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.

Allergic Aspergillus Rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a unique variety of chronic polypoid rhinosinusitis usually in atopic individuals, characterized by presence of eosinophilic mucin and fungal hyphae in paranasal sinuses without invasion into surrounding mucosa. It has emerged as an important disease involving a large population across the world with geographic variation in incidence and epidemiology. The disease is surrounded by controversies regarding its definition and etiopathogenesis. A working group on "Fungal Sinusitis" under the International Society for Human and Animal Mycology (ISHAM) addressed some of those issues, but many questions remain unanswered. The descriptions of "eosinophilic fungal rhinosinusitis" (EFRS), "eosinophilic mucin rhinosinusitis" (EMRS) and mucosal invasion by hyphae in few patients have increased the problem to delineate the disease. Various hypotheses exist for etiopathogenesis of AFRS with considerable overlap, though recent extensive studies have made certain in depth understanding. The diagnosis of AFRS is a multi-disciplinary approach including the imaging, histopathology, mycology and immunological investigations. Though there is no uniform management protocol for AFRS, surgical clearing of the sinuses with steroid therapy are commonly practiced. The role of antifungal agents, leukotriene antagonists and immunomodulators is still questionable. The present review covers the controversies, recent advances in pathogenesis, diagnosis, and management of AFRS.

Anatomic findings in revision endoscopic sinus surgery: Case series and review of contributory factors

Background:

It is recognized that patients who undergo endoscopic sinus surgery (ESS) do not always achieve control of their disease. The causes are multifactorial; variations in surgical practice have been identified as possible factors in refractory disease.

Objective:

To reflect on the frequent anatomic findings of patients with chronic rhinosinusitis (CRS) who require revision ESS.

Methods:

A retrospective review of patients who required revision ESS at a tertiary institution over a 3-year period. Patients for whom maximal medical therapy failed for CRS underwent computed tomography of the paranasal sinuses and image-guided surgery. Surgical records of anatomic findings were reviewed and analyzed.

Results:

Over 3 years, a total of 75 patients underwent revision procedures, 28% of all ESS performed in the unit. The most frequent finding was a residual uncinate process in 64% of the patients (n = 48); other findings included a maxillary antrostomy not based on the natural ostium of the maxillary sinus in 47% (n = 35), an oversized antrostomy in 29% (n = 22), resected middle turbinates in 35% (n = 26), middle meatal stenosis in 15% (n = 11), synechiae in 29% (n = 22), and osteitic bone that required drilling in 13% (n = 10).

Conclusion:

Surgical technique can give rise to anatomic variations that may prevent adequate mucociliary clearance and medication delivery, which leads to failure in ESS in patients with CRS. This study demonstrated the surgical findings encountered in revision ESS that should be highlighted in the training of Ear, Nose and Throat surgeons to help prevent primary failure and reduce health care costs.

Allergic Fungal Sinusitis: Expanding the Clinicopathologic Spectrum

OBJECTIVE

We sought to determine whether histologic tissue invasion occurs in allergic fungal sinusitis (AFS) and, if so, to identify clinical indicators for the same. Study design and setting We conducted a retrospective case record review of all 28 AFS cases identified by histology over a 32-month period at a tertiary care referral center. All histologic specimens were reevaluated for features of invasive pathology, and case records were correlated for clinical, radiologic, or laboratory parameters associated with such invasion.

RESULTS

In addition to the universal finding of the characteristic allergic mucin with fungal elements on histopathologic examination of the sinus luminal contents, 6 cases (21%) had additional evidence of mucosal invasion as indicated by granulomatous inflammation and branching septate fungal hyphae in the submucosal tissues. Such coexistent invasion was associated with advanced disease as indicated by a higher incidence of orbital involvement on clinical evaluation (P = 0.024), and extrasinus spread (intraorbital or intracranial spread) on the computed tomography evaluation (P = 0.003). The single death that occurred on follow-up was in a patient with coexistent invasion.

CONCLUSION

Advanced AFS may be complicated by histologic evidence of tissue invasion.

SIGNIFICANCE

The noninvasive and invasive forms of fungal sinusitis are not necessarily discrete and may coexist in the same patient. Clinical features of orbital involvement or computed tomography manifestations of extrasinus spread should alert the clinician to the possibility of invasion.

Pathogenesis of eosinophilic chronic rhinosinusitis

Eosinophilic chronic rhinosinusitis (ECRS) is considered a refractory and intractable disease. Patients with ECRS present with thick mucus production, long-term nasal congestion, loss of sense of smell, and intermittent acute exacerbations secondary to bacterial infections. Despite medical and surgical interventions, there is a high rate of recurrence with significant impairment to quality of life. The recent increasing prevalence of ECRS in south Asian countries and the strong tendency of ECRS to reoccur after surgery should be considered. The majority of cases need repeat surgery, and histological examinations of these cases show eosinophilic-dominant inflammation. The degradation and accumulation of eosinophils, release of cytokines, and mucus secretion have important roles in the pathogenesis of ECRS. ECRS differs from non-ECRS, in which eosinophils are not involved in the pathogenesis of the disease, and also in terms of many clinical characteristics, blood examination and nasal polyp histological findings, clinical features of the disease after surgery, efficacy of medications, and computed tomography findings. This review describes the clinical course, diagnosis, and treatment of ECRS as well as its pathophysiology and the role of eosinophils, mucus, cytokines, and other mediators in the pathogenesis of ECRS.