Allergic fungal rhinosinusitis

High M2/M1 Macrophage Ratio Observed in Nasal Polyps Formed in Allergic Fungal Rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) shares similarities with eosinophilic chronic rhinosinusitis (ECRS), both characterized by intractable nasal polyps. The key distinction lies in the presence of fungal infection within the nasal cavity. While ECRS nasal polyps are known for significant infiltration of M2 macrophages and eosinophils, as well as an increase in high endothelial venule (HEV)-like vessels, these features are less commonly reported in AFRS. This study compared clinicopathological findings between AFRS (n=10), ECRS (n=12), and non-ECRS (n=10) patients' nasal polyps using immunohistochemical analysis for CD163 and CD68 to assess the M2/M1 macrophage ratio, and peripheral lymph node addressin (PNAd) and CD34 to evaluate the proportion of HEV-like vessels. AFRS showed a significantly higher number of CD163-positive M2 macrophages and an increased M2/M1 ratio compared with ECRS. However, the percentage of HEV-like vessels and the number of eosinophils infiltrating the nasal polyps were similar in both AFRS and ECRS. The observed increase in M2 macrophages in AFRS nasal polyps is presumed to be induced by fungal infection in the nasal cavity, in comparison with ECRS. These results highlight the distinctive immunological profiles of AFRS and ECRS, emphasizing the role of macrophage polarization in their pathogenesis.

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.

Varied Clinical Presentations of Allergic Fungal Rhinosinusitis-A Case Series

Fungal sinusitis is broadly classified into invasive and non invasive types. Invasive type presents with fungal hyphae within the mucosa, submucosa, bone, or blood vessels of the paranasal sinuses and includes Acute Invasive Fungal Sinusitis, Acute Fulminant, Chronic Invasive Fungal Sinusitis, Chronic Granulomatous Fungal Sinusitis. Invasive forms of fungal rhinosinusitis are rare and confined to groups of patients who are immunocompromised (Key in Fungal rhinosinusitis). Noninvasive type shows absence of fungal hyphae within the mucosa paranasal sinuses. It includes Allergic Fungal rhinosinusitis, Fungus Ball (fungus mycetoma). The study was performed on a total of 30 patients, in Department of Otorhinolaryngology, at our hospital after getting approved by the Instituitional Human Ethical Committee. We selected 30 patients diagnosed with allergic fungal sinusitis and studied their varied clinical presentations and treatment for a period of 1 year. It was a prospective case series type of study. Patients who presented with symptoms of allergic fungal rhinosinusitis were included. Patients who were referred with complaints of proptosis, diplopia were also included to rule out allergic fungal rhinosinusitis and its complications. Patients diagnosed with chronic granulomatous infection of nose and invasive fungal sinusitis were excluded. Evaluation of patients involved a detailed case history followed by clinical examination and radiologic investigation. After getting proper consent, we did a study of 30 patients who presented to our outpatient department with complaints of sinusitis. Our study included 12 male and 18 female patients. Among these patients, all of them had complaints of frequent allergic rhinosinusitis, nose block, facial heaviness. 12 among them had olfactory disturbances, reduced perception of smell. 4 patients presented with visual disturbances and proptosis which subsided after endoscopic sinus surgery was done.24 among these patients had presence of allergic fungal mucin in their nasal secretions and 10 patients had history of associated atopy and asthma and elevated Ig E levels. And 20 of these patients showed high eosinophil counts. All these patients in our case series were under the age group 22-70 years. These patients were treated with a course of nasal sprays and preoperative steroids in case of extensive polyposis and were taken up for functional endoscopic sinus surgery. Polypoidal mucosa was removed, diseased tissue was cleared, sinus blockage was released and fungal mucin/tissue bits were sent for histopathological analysis, KOH mount and fungal culture. This study included a series of cases which showed a wide range of the various clinical presentations that occur in cases of allergic fungal rhinosinusitis, its diagnosis and treatment. The advantage of this study was we had analyzed a good number of cases with varied presentations. Since AFRS is closely related with EMRS, CRS a proper clinical, radiological and immunological evaluation of the cases help in knowing the correct diagnosis and treatment.

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.

A Comparison of Sphenoid Sinus Osteoneogenesis in Aspirin-Exacerbated Respiratory Disease

BACKGROUND

Aspirin-exacerbated respiratory disease (AERD) is characterized by excessive leukotriene production, diffuse polyp burden and osteitic bone changes. These bony changes have not been previously characterized.

OBJECTIVE

The aim of this radiographic study is to characterize the bony changes noted on computed tomography (CT) scans of the sphenoid sinus in patients with AERD compared to other diseased sinonasal inflammatory states and non-diseased controls.

METHODS

A retrospective review of 43 patients with clinically confirmed AERD were included and compared to 22 non-diseased, 9 allergic fungal sinusitis, and 43 chronic rhinosinusitis controls (23 without polyps and 18 with polyps). Comparative measurements were performed using fine-cut CT scans. Sites of comparison were the intersinus septum, the left and right lateral sphenoid wall, the roof, and left and right floor of the sphenoid sinus. Standardized measurements were averaged by two separate rhinologists.

RESULTS

Patients with AERD had an average statistically significant increase in bone thickness compared to healthy and diseased controls in nearly every site with the most pronounced changes in the intersinus septum (p < 0.05).

CONCLUSION

Patients with AERD have significantly increased thickness of the sphenoid bone compared to control groups with the most pronounced difference in the intersinus septum. These findings may help clinicians increase suspicion for a diagnosis of AERD who clinically have diffuse nasal polyposis.

Bone Regeneration in Allergic Fungal Rhinosinusitis: Post-treatment Image Follow Up

Background: Bone erosion is a feature of allergic fungal rhinosinusitis (AFRS). The incidence of bone regeneration after treatment is unknown. The objective of this study is to evaluate the fate of bone erosion in AFRS.

Materials and methods: A retrospective chart review was conducted for all AFRS patients who had preoperative evidence of bone erosion on the computed tomography (CT) of the paranasal sinus (PNS) and at least one postoperative image. We used the bone erosion score (BES) as a valid tool to evaluate the preoperative bone erosion extension and the rate of regeneration on postoperative images.

Results: A total of 40 patients met our enrollment criteria. Of these, 30 patients underwent CT within nine months postoperatively (mean baseline BES: 9.07, SD: 8.11), 33 patients underwent CT between nine and 18 months postoperatively (mean baseline BES: 9.36, SD: 8.80), and 34 patients underwent CT after 18 months postoperatively (mean baseline BES: 8.56, SD: 7.69). The BES improved by 88.92% within nine months postoperatively with a follow-up BES of 0.93 (SD: 1.65), by 90.29% between nine and 18 months with a follow-up BES of 0.91 (SD: 2.15), and by 96.57% after 18 months with a follow-up BES of 0.29 (SD: 0.62). Complete bone regeneration occurred in 27 patients (67.50%); this was noted within nine months in 21 patients and after 18 months in six. Among them, 16 were male and 11 were female (p = 0.75). Regarding their ages, eight were pediatric and 19 were adult patients (p = 0.31).

Conclusion: Bone erosion in AFRS is a mostly reversible process. Complete bone regeneration occurred in more than two-thirds of patients within a short period of time.

Study toward resolving the controversy over the definition of allergic fungal rhinosinusitis

Dysbiosis of the microbiome on the airway mucosa leads to the development of chronic inflammatory and allergic disorders. The aim of this study was to consider the potential diagnostic criteria for allergic fungal rhinosinusitis (AFRS) and nonallergic fungal rhinosinusitis (FRS), and the role of fungal presence in an environment for the development of AFRS. In this study, 136 patients were divided into two groups: patients with positive specific immunoglobulin E (sIgE) and fungal finding (AFRS group), and patients with negative sIgE and positive fungal finding (FRS group). The study design included: anamnesis data, sIgE, eosinophil count and skin-prick test, rhinology and computerized tomography (CT) observation and mycological finding. Our results showed: (i) the prevalence in Serbia is: AFRS 1.3%, FRS 2.8%; (ii) 30.4% patients with sIgE+ had more often severe and recurrent chronic rhinosinusitis (CRS) (P = .005) and the presence of polyps (P = .025); (iii) 46.4% patients with sIgE+ had positive fungi on the sinonasal mucosa and were considered as AFRS; (iv) patients with AFRS had more frequent asthma (P = .024) and chronicity of CRS >10 years (P = .000). The persistent fungal presence and prolonged duration of CRS could be a silent threat for the progression of inflammation and development of FRS. Lavage with hypertonic-NaCl should be included in the everyday hygiene routine in an effort to decrease fungal load and antigenic exposure. The presence of allergological parameters and better response to corticosteroid therapy in AFRS patients should be considered as crucial diagnostic criteria for AFRS.

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.

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.

Objective radiographic density measurements of sinus opacities are not strong predictors of noninvasive fungal disease

BACKGROUND

High-density paranasal sinus opacities are often deemed consistent with fungal elements. No studies of objective quantitative radiographic density measures have been performed to support this assertion.

METHODS

A consecutive series of 120 patients with chronic rhinosinusitis who underwent maxillary antrostomy with microbiological evaluation of contents within 60 days of sinus computed tomography scanning was investigated. Radiographic density characteristics of opacities in cultured maxillary sinuses (minimum, maximum, average, and standard deviation of Hounsfield units [HUstd]) were recorded. Receiver operator characteristic (ROC) curves were used to analyze the accuracy of radiographic characteristics in predicting fungal opacities.

RESULTS

Of 133 maxillary sinus opacities, 22 were ultimately consistent with noninvasive fungal disease: 11 allergic fungal rhinosinusitis and 11 fungal balls. Fungal balls had higher-density components and were more heterogeneous and allergic fungal mucin was generally more radiodense. These findings were reflected by statistically significant ROC curves for maximum HU (p = 0.019) and HUstd (p = 0.023) for fungal balls and for average HU (p = 0.002) for allergic fungal mucin. A maximum HU cutoff of 334.0 detected fungal balls with 90.9% sensitivity and 72.7% specificity. An average HU cutoff of 42.9 HU detected allergic fungal mucin with 100% sensitivity and 46.3% specificity, although specificity improved to 73.2% with inclusion of nasal polyposis as a second requirement.

CONCLUSION

Higher average HU more accurately predicts allergic fungal mucin whereas heterogeneity/high-density components more accurately predict fungal balls. No objective radiographic density measure, in isolation, is both sensitive and specific in predicting noninvasive fungal sinusitis.

Omalizumab therapy for refractory allergic fungal rhinosinusitis patients with moderate or severe asthma

PURPOSE

1. To assess the efficacy of omalizumab therapy in improving sinonasal outcomes in refractory allergic fungal rhinosinusitis (AFRS) patients with moderate or severe asthma. 2. To determine if omalizumab therapy reduces the usage of corticosteroids or antifungal therapy in AFRS patients

METHOD

DESIGN

The clinical charts of patients with AFRS with moderate or severe asthma who received at least three subcutaneous injections of omalizumab therapy between 1st January 2012 and 1st May 2014 were retrospectively reviewed. These patients had undergone bilateral functional endoscopic sinus surgery (FESS) and failed adjunct medical treatments (oral or topical corticosteroids and/or antifungal therapy) prior to omalizumab therapy.

RESULTS

Seven patients met the inclusion criteria and were included in this study. The mean age of the patients was 48.14. The average number of subcutaneous omalizumab injections was 7.57 (range 6-11) with a mean dosage of 287mg (range 225-375mg). The mean pre-omalizumab treatment Sino-Nasal Outcome Test-22 (SNOT-22) score was 52.14 while the mean post-omalizumab treatment SNOT-22 score was 35.86 (31% improvement). The mean pre-omalizumab therapy Phillpott-Javer endoscopic score (over the last one year before omalizumab therapy) was 36 while the mean post-omalizumab therapy endoscopic score (from the last clinic visit) was 14 (61% improvement). Omalizumab therapy reduced the dependence of AFRS patients on corticosteroid and antifungal treatments.

CONCLUSION

Omalizumab therapy can be considered as a potential adjunct for the treatment for patients with refractory AFRS with moderate or severe asthma. However, larger prospective studies to confirm the findings of this study will be required.

The Etiology and Pathogenesis of Chronic Rhinosinusitis: a Review of Current Hypotheses

Chronic rhinosinusitis (CRS) is a broad clinical syndrome that is characterized by prolonged mucosal inflammation of the nose and paranasal sinuses, and is typically divided into two subtypes based on the presence or absence of nasal polyps. The etiology and pathogenesis of both forms remain areas of active research. Over the last 15 years, a number of hypotheses have been proposed to explain all or part of the clinical CRS spectrum. These hypotheses reflect the concept that CRS results from a dysfunctional interplay between individual host characteristics and factors exogenous to the host. Six broad theories on CRS etiology and pathogenesis are discussed as follows: (1) the "fungal hypothesis," (2) the "superantigen hypothesis," (3) the "biofilm hypothesis," and (4) the "microbiome hypothesis," all of which emphasize key environmental factors, and (5) the "eicosanoid hypothesis" and (6) the "immune barrier hypothesis," which describe specific host factors. These theories are reviewed, and the evidence supporting them is critically appraised.

Outcomes of pressure-induced cranial neuropathies from allergic fungal rhinosinusitis

OBJECTIVES

Allergic fungal rhinosinusitis (AFRS) may present with significant bone erosion of the orbital walls or cranial base. Although proptosis is fairly common, cranial neuropathies are rarely reported. The objectives of this study are to describe strategies for AFRS-induced neuropathies and evaluate ophthalmologic outcomes following endoscopic sinus surgery.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary referral center.

SUBJECT AND METHODS

A retrospective review identified 9 patients treated from 2008 to 2014 with AFRS-induced cranial neuropathies. Data regarding patient demographics, preoperative imaging, ophthalmologic symptoms, surgical intervention, histopathologic findings, and postoperative sinonasal and ophthalmologic outcomes were recorded.

RESULTS

Patients with AFRS (average age, 38 years) presented with optic neuropathy or abducens nerve palsy. Clinical presentation included unilateral visual loss secondary to optic nerve compression (n=5), diplopia from unilateral (n=2) or bilateral (n=1) abducens nerve palsy, and bitemporal hemianopsia secondary to optic chiasm compression (n=1). On average, the duration of ocular symptoms was 17 days. All patients underwent endoscopic surgical decompression of the sinuses and oral steroid therapy. Two individuals had an additional optic nerve decompression at the time of surgery. Seven patients had complete return of nerve function, whereas 2 had partial recovery at an average of 5 weeks following surgery.

CONCLUSION

Bone erosion of the sphenoid sinus walls by AFRS can lead to compression of surrounding neural structures producing cranial neuropathies. Identification of these symptoms and prompt surgical decompression and removal of disease, along with aggressive medical therapy, provided excellent outcomes in the current series of patients.

Immunotherapy in allergic fungal sinusitis: The controversy continues. A recent review of literature

Allergic fungal sinusitis (AFS), also referred to as allergic fungal rhinosinusitis (AFRS), is a noninvasive, eosinophilic form of recurrent chronic allergic hypertrophic rhinosinusitis. AFS has distinct clinical, histopathological, and prognostic findings that differentiate it from other forms of sinusitis. The core pathogenesis and optimum treatment strategies remain debated. Concerns surround the use of immunotherapy for AFS because allergen-specific immunoglobulin G (IgG) induced by immunotherapy could theoretically incite a Gell and Coombs type III (complex mediated) reaction. Type I hypersensitivity is established by high serum levels of allergen-specific IgE to various fungal antigens and positive Bipolaris skin test results. Type III hypersensitivity is established by an IgG-mediated process defined by the presence of allergen-specific IgG that forms complexes with fungal antigen inducing an immunologic inflammatory response. These reveal the multiple immunologic pathways through which AFS can impact host responses. Recent literature establishing benefits of fungal immunotherapy and no evidence of type III–mediated reactions, severe local reactions, or delayed reactions, indicate that application of AFS desensitization is a reasonable therapeutic strategy for this difficult to manage entity. Our review should encourage further clinical acceptance of AFS desensitization because the existing literature on this subject shows benefits of fungal immunotherapy and no evidence of type III–mediated reactions, severe local reactions, or delayed reactions.

Bacterial-induced epithelial damage promotes fungal biofilm formation in a sheep model of sinusitis

BACKGROUND

Fungal biofilms have been discovered in chronic rhinosinusitis (CRS) patients, but factors contributing to their establishment are obscure. A recent animal study showed bacterial co-inoculation was required. We examine the role of 4 bacterial species and a cilia toxin on fungal biofilm formation in a sheep sinusitis model. The importance of epithelial integrity on fungal biofilm formation is also examined.

METHODS

Forty-eight frontal sinuses were inoculated with Aspergillus fumigatus alone, with 1 of 4 bacteria, or a cilia toxin. Bacterial and fungal biofilm was determined using confocal scanning laser microscopy. Inflammation and cilia integrity were assessed using light microscopy and transmission electron microscopy, respectively.

RESULTS

No fungal biofilm formed when inoculated alone. Florid fungal biofilm developed in more than 75% of sinuses associated with bacterial biofilm of all species, except Haemophilus influenzae, which failed to establish bacterial biofilm. Fungal biofilm also established in association with cilia toxin. Significant cilial damage was incited by all bacterial biofilms and cilia toxin, and was associated with fungal proliferation. Fungal biofilm formation did not significantly increase mucosal inflammation or epithelial damage over that caused by the bacteria or cilia toxin alone.

CONCLUSION

Bacterial biofilms cause sinonasal mucosal inflammation and epithelial injury, which provides conditions appropriate for fungal biofilm proliferation. The role of cilia in sinonasal mucosal defense against fungal organisms has been demonstrated. Without such an insult, fungal biofilms fail to proliferate in occluded sinuses. Improving cilial recovery postoperatively and treating bacterial biofilms may be key factors in reducing recalcitrance in allergic fungal rhinosinusitis patients.

Allergic fungal sinusitis in children

Allergic fungal sinusitis (AFS) is a subtype of eosinophilic chronic rhinosinusitis (CRS) characterized by type I hypersensitivity, nasal polyposis, characteristic computed tomography scan findings, eosinophilic mucus, and the presence of fungus on surgical specimens without evidence of tissue invasion. This refractory subtype of CRS is of the great interest in the pediatric population, given the relatively early age of onset and the difficulty in managing AFS through commercially available medical regimens. Almost universally, a diagnosis of AFS requires operative intervention. Postoperative adjuvant medical therapy is a mainstay in the treatment paradigm of pediatric AFS.

Pathophysiology, favoring factors, and associated disorders in otorhinosinusology

The pathogenesis of rhinosinusitis (RS) is related to inflammation, caused by infections in the acute form of the disease but also by other agents in the chronic forms. Cytology allows to evaluate the defensive components, such as hair cells and muciparous cells, while the presence in the nasal mucosa of eosinophils, mast cells, bacteria and/or fungal hyphae, or spores indicates the nasal pathology. The anatomic and physiologic characteristics of the otorhinosinusal system account for the frequent concomitant involvement of the different components. The pivotal pathophysiologic sites are the ostiomeatal complex, the spheno-ethmoidal recess, and the Eustachian tube. The latter is the link with acute otitis media (AOM), which is the most common disease in infants and children and has major medical, social, and economic effects. Moreover, because of the strict relationship between upper and lower airways, nasal sinus disease may contribute to asthma and sinusitis may be considered as an independent factor associated with frequent severe asthma exacerbations. Concerning the role of allergy, the available data do not permit to attribute a central role to atopy in sinusitis and thus allergy testing should not be a routine procedure, while an allergologic evaluation may be indicated in children with OM, especially when they have concomitant rhinitis.