Fungal rhinosinusitis: diagnosis and therapy

Clinical Manifestations of Human Exposure to Fungi

Biological particles, along with inorganic gaseous and particulate pollutants, constitute an ever-present component of the atmosphere and surfaces. Among these particles are fungal species colonizing almost all ecosystems, including the human body. Although inoffensive to most people, fungi can be responsible for several health problems, such as allergic fungal diseases and fungal infections. Worldwide fungal disease incidence is increasing, with new emerging fungal diseases appearing yearly. Reasons for this increase are the expansion of life expectancy, the number of immunocompromised patients (immunosuppressive treatments for transplantation, autoimmune diseases, and immunodeficiency diseases), the number of uncontrolled underlying conditions (e.g., diabetes mellitus), and the misusage of medication (e.g., corticosteroids and broad-spectrum antibiotics). Managing fungal diseases is challenging; only four classes of antifungal drugs are available, resistance to these drugs is increasing, and no vaccines have been approved. The present work reviews the implications of fungal particles in human health from allergic diseases (i.e., allergic bronchopulmonary aspergillosis, severe asthma with fungal sensitization, thunderstorm asthma, allergic fungal rhinosinusitis, and occupational lung diseases) to infections (i.e., superficial, subcutaneous, and systemic infections). Topics such as the etiological agent, risk factors, clinical manifestations, diagnosis, and treatment will be revised to improve the knowledge of this growing health concern.

Low Incidence of Allergic Fungal Rhinosinusitis in Japanese Patients

Background:

Allergic fungal rhinosinusitis (AFRS) is a noninvasive fungal disease of the sinuses with a very high recurrence rate. A very small number of Japanese cases have been reported.

Material and methods:

The subjects were 6 patients with AFRS out of 429 patients who underwent endoscopic sinus surgery at Kagawa Rosai Hospital between December 2011 and November 2017. We retrospectively examined the clinical features and outcomes of these 6 patients.

Results:

The incidence of AFRS was 1.4% (6/429). Allergic fungal rhinosinusitis was unilateral in 5 cases and bilateral in 1. Computed tomography revealed hyperdense areas representing allergic mucin, but no patient exhibited bone erosion. Magnetic resonance imaging showed hypointense or no signal regions at the locations of allergic mucin. Postoperatively, 1 patient developed recurrence. Because the recurrent patient had no significant symptoms, he refused further surgery and received drug therapy. Preoperative eosinophil counts and total IgE levels were elevated in all patients; postoperatively, both remained high in the patient who developed recurrence. Postoperative treatments included steroid therapy and nasal irrigation.

Conclusions:

Allergic fungal rhinosinusitis is less prevalent in Japan than in Western nations. Peripheral blood eosinophil and serum IgE values may be used as the biomarkers.

Significance:

Allergic fungal rhinosinusitis is prone to recurrence. Postoperative treatment including steroid therapy is important in the management of AFRS.

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.

Contribution of molecular tools for the diagnosis and epidemiology of fungal chronic rhinosinusitis

Chronic rhinosinusitis (CRS) rank second at chronic inflammatory diseases in industrialized countries and are an important public health concern. Diagnosis relies on a set of arguments including clinical signs, imaging, histopathologic and mycological analyses of sinus specimens, collected during nasal endoscopy. The sensitivity of fungal cultures is reported to be poor, even when direct examination is positive, thus the epidemiology of fungal chronic sinusitis is ill-known. This study evaluated the sensitivity of molecular diagnosis in 70 consecutive samples (61 patients with CRS) analysed at the University Hospital of Rennes during a 3-year period. DNA detection was performed using a conventional PCR method targeting the ITS1/ITS2 sequence and the resulting amplification products were sequenced. Fungal CRS was proven in 42 patients (69%), of which only 20 (48%) had a positive culture. 37/42 (88%) patients were diagnosed with a fungus ball, 3 with allergic fungal CRS and 2 with undetermined fungal CRS. PCR was positive in all 42 cases and direct sequencing allowed to identify fungi in all cases but one, and detected multiple infection in 3. Aspergillus fumigatus was present in 69% of patients; Cladosporium cladosporoides in 9.5%, Scedosporium sp., A. nidulans and A. flavus in 7% each. In 2/19 patients with negative direct examination, sequencing analysis revealed the presence of Capnobotryella sp. and C. cladosporoides, in clinical settings compatible with fungal sinusitis. In conclusion, ITS1/ITS2 PCR had a twice better sensitivity than culture, and combined sequencing provides accurate epidemiological data on fungal CRS.

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.

Chronic rhinofacial basidiobolomycosis caused by Basidiobolus ranarum: Report of a case from Aseer Region, Kingdom of Saudi Arabia

We present a case of fungal sinusitis caused by Basidiobolus ranarum in a 22-year-old male patient with chronic rhinosinusitis in Aseer region, Kingdom of Saudi Arabia. The patient was admitted with nasal obstruction accompanied by itching, sneezing, rhinorrhea, epistaxis and recurrent headache. Axial computed tomography (CT) scan of the paranasal sinuses showed a clear left facial swelling chronic inflammation and granulomata. Basidiobolus ranarum fungus was isolated on Sabouraud dextrose agar from a biopsy specimen. The organism was characterized by flat, yellowish-grey, glabrous, becoming radially folded fungus that under the microscope showed broad vegetative hyaline hyphae that bear zygospores with protuberances. The patient made good recovery and was discharged home with no recurrences after receiving oral itraconazole and removal of the polyps surgically.

Invasive Fungal Sinusitis Involving the Orbital Apex in a Patient with Chronic Renal Failure

An 82-year-old man with chronic renal failure presented with invasive fungal sinusitis involving the right orbital apex. Intravenous liposomal amphotericin B was immediately administered with an intravenous sodium supplement. Subsequently, endoscopic sinus surgery was performed. Aspergillus fumigatus was detected in nasal discharge culture on day 12. Because the patient's renal function had deteriorated by this time, therapy was changed to nasal inhalation of amphotericin B, which was discontinued after 1 month, and oral administration of voriconazole, which was discontinued after 2 months. During 6-month follow-up, the patient did not show recurrence of sinusitis or further decrease in renal function.

Categorization and clinicopathological features of chronic rhinosinusitis with eosinophilic mucin in a korean population

Objectives

Chronic rhinosinusitis (CRS) with eosinophilic mucin is relatively rare in Korea. We categorized CRS patients with characteristic eosinophilic mucin into several groups and compared the groups based on their clinicopathological features.

Methods

In total, 52 CRS patients with eosinophilic mucin were enrolled. Based on the presence or absence of an allergy (A) to a fungus or fungal element (F) in the mucin, the patients were divided into four groups: allergic fungal rhinosinusitis (AFRS, A+F+), AFRS-like sinusitis (A+F-), eosinophilic fungal rhinosinusitis (EFRS, A-F+), and eosinophilic mucin rhinosinusitis (EMRS, A-F-). Clinical and immunological variables were compared between the groups.

Results

There were 13 patients in the AFRS group, 13 in the EFRS group, and 26 in the EMRS group. No patient was assigned to the AFRS-like sinusitis group. The AFRS group showed a significantly higher association with allergic rhinitis than did the EFRS and EMRS groups. The mean total serum IgE level in the AFRS patients was significantly higher than in the EFRS and EMRS patients. While 7.7% of the patients with AFRS and EFRS were asthmatic, 65.4% of the patients with EMRS had bronchial asthma. In the AFRS and EFRS groups, 31% had bilateral disease, in contrast to 100% of EMRS patients with bilateral disease. The prevalence of high attenuation areas by computed tomography was significantly higher in the AFRS group than in the EMRS group, and the mean Hounsfield unit values of the areas of high attenuation in the AFRS patients were significantly greater than those in the EMRS patients.

Conclusion

AFRS is believed to be an allergic response to colonizing fungi in atopic individuals. In EFRS, local allergies to fungi may play a role in the pathogenesis of the disease. EMRS is thought to be unconnected with fungal allergies.

Sinus fungus ball in the Japanese population: clinical and imaging characteristics of 104 cases

Sinus fungus ball is defined as noninvasive chronic fungal rhinosinusitis occurring in immunocompetent patients with regional characteristics. The clinical and imaging characteristics of paranasal sinus fungus ball were retrospectively investigated in 104 Japanese patients. All patients underwent endoscopic sinus surgery. Preoperative computed tomography (CT), magnetic resonance (MR) imaging, age, sex, chief complaint, causative fungus, and clinical outcome were analyzed. Patients were aged from 25 to 79 years (mean 58.8 years). Female predominance was noted (58.7%). Most common symptoms were nasal discharge and facial pain. CT showed high density area in 82.0% of the cases (82/100), whereas T2-weighted MR imaging showed low intensity area in 100% of the cases (32/32). Histological examination showed that most causative agents were Aspergillus species (94.2% (98/104)). Culture test was positive for 16.7% (11/66). Recurrence was found in 3.2% (3/94). Older age and female predominance were consistent with previous reports. MR imaging is recommended to confirm the diagnosis.

Sinonasal risk factors for the development of invasive fungal sinusitis in hematological patients: Are they important?

Invasive fungal sinusitis (IFS) is a highly aggressive infection that can affect hematologic patients. The classically described general risk factors, however, do not fully explain the development of IFS in a small percentage of cases. This study examined the impact of anatomic sinonasal factors and environmental factors on the development of IFS in high-risk patients. Medical records and computed tomography (CT) scans of patients admitted to our institution who were at high risk of developing IFS were retrospectively reviewed. Twenty-seven patients of 797 fulfilled the inclusion criteria. Patients affected by IFS were compared with patients not affected to identify possible sinonasal and environmental risk factors of IFS. Seven patients were excluded because of the lack of adequate radiological images. Six of the 20 eligible patients were assigned to the study group of patients affected by IFS and the remaining 14 patients were assigned to the control group. All but one case developed the infection during the summer with a significantly higher mean environmental temperature (p = 0.002). Anatomic nasal alterations were found in all patients affected by IFS and were significantly more frequent than in the control group (p = 0.014). It would be advisable to have patients with hematologic risk factors of IFS, especially during the summer period, undergo endoscopic nasal assessment. Furthermore, a CT finding of anatomic nasal alterations, such as anterior nasal septum deviation causing nasal obstruction, should increase the suspicion of IFS in case of the occurrence of nasal symptoms.

The Role of Antifungal Therapy in the Prevention of Recurrent Allergic Fungal Rhinosinusitis after Functional Endoscopic Sinus Surgery: A Randomized, Controlled Study

Allergic fungal rhinosinusitis (AFRS) is the most common form of fungal sinus disease. Its recurrence rate is high despite numerous strategies to prevent it. We conducted a study to assess the effect of systemic and topical antifungal agents—both separately and in combination—in preventing recurrence of AFRS following functional endoscopic sinus surgery (FESS). Our initial study population was made up of 50 adults who were diagnosed with AFRS by clinical, radiologic, histopathologic, and laboratory workup and who subsequently underwent FESS. Postoperatively, these patients were randomized into 5 different treatment groups matched for sex, age, and socioeconomic status. Four of the groups received a different antifungal regimen in addition to convenient medical treatment (CMT), while a fifth group served as a control. The antifungal regimens included oral itraconazole (group A), fluconazole nasal spray (group B), combined oral itraconazole and nasal fluconazole (group C), and irrigation with a fluconazole solution through the nasal fossa (group D); the group of 10 controls (group E) received CMT only. A total of 41 patients were available for follow-up (9 mo maximum). Recurrence rates in the 5 groups were 66.7, 10.0, 14.3, 28.6, and 75.0%, respectively. Based on our findings, we conclude that treatment with topical fluconazole as either a nasal spray or an irrigation solution can significantly reduce the rate of recurrence of AFRS after FESS.

Prevalence of extramucosal fungal elements in sinonasal polyposis: a mycological and pathologic study in an Egyptian population

OBJECTIVE AND HYPOTHESIS

The objective of the study was to define the true incidence of fungal elements in the nasal and sinus mucous in cases of chronic rhinosinusitis (CRS) with bilateral polyposis compared with normal controls-in an Egyptian African population-via mycological and histologic techniques.

STUDY DESIGN

This study was conducted prospectively on 100 patients with the clinical diagnosis of CRS with bilateral nasal polyposis. Fifty volunteers with no history of nasal or paranasal sinus disease served as a control group.

RESULTS AND CONCLUSION

The postulated criteria for the diagnosis of allergic fungal sinusitis were present in 92% of CRS with polyposis, suggesting that fungi are involved in the disease process of most CRS patients.

Should Voriconazole be the Primary Therapy for Chronic Invasive Sinus Aspergillosis (CISA)?

Introduction

Invasive sinus aspergillosis infection has been reported with increasing frequency in the last decade, especially, in immunocompromised patients with chronic invasive sinus aspergillosis (CISA). The gold standard for treatment has been wide surgical debridement, intravenous administration of antifungal agents, such as amphotericin B, but the prognosis remains poor. Newer antifungal agents are being tried but no standard treatment option with new antifungal agents has yet been established for chronic invasive fungal sinusitis. Therefore, we undertook this study to evaluate the efficacy of voriconazole in patients of chronic invasive sinus aspergillosis.

Materials and methods

This study is a prospective randomized unblinded study with primary aim of evaluating the feasibility and effectivity of voriconazole in patients of chronic invasive sinus aspergillosis with intraorbital or intracranial extension, and secondarily to compare voriconazole with amphotericin B therapy in patients with chronic invasive sinus aspergillosis.

Observations and results

Thirty-three patients who fulfilled the eligibility criteria were included in this study. There were 18 patients enrolled in group I who received amphotericin therapy and 15 patients in group II who received voriconazole therapy. Out of 33 patients, 9 patients had complete response, 10 had partial response, in eight patients disease became stable and there were seven failures. Overall 50% patients had a successful outcome in group I, whereas 60% had a successful outcome in group II receiving oral voriconazole. On comparing only in extradural group, 5/10 had a successful outcome in group I receiving amphotericin B, whereas 8/12 (66.7%) had a successful outcome in group 2 receiving voriconazole. There was significant difference between adverse reactions of the two drugs, with amphotericin B having a significant renal and cardiotoxicity as compared to voriconazole; though patients on voriconazole developed skin rashes which were transient and disappeared on completion of the therapy.

Conclusion

The present series demonstrates that oral voriconazole can be the primary line of therapy in chronic invasive sinus aspergillosis in carefully monitored immunocompetent cases. Multicentric, randomized studies are required to define disease definition, duration and successful outcome.

Allergic fungal rhinosinusitis: detection of fungal DNA in sinus aspirate using polymerase chain reaction

Objective:

This study investigated allergic fungal rhinosinusitis cases, and aimed to compare the detection of fungi in sinus aspirate by culture and by polymerase chain reaction assay, and to relate the presence of fungi in the nasal sinuses to the type of fungal allergen causing disease.

Methods:

Sixty-eight cases of allergic fungal rhinosinusitis underwent fungal culture and polymerase chain reaction assay for universal fungal, aspergillus and bipolaris DNA. Aspergillus-specific immunoglobulin E levels were measured in sinus aspirate, and total serum immunoglobulin E levels were calculated. A control group of 10 cases was included in the study.

Results:

Of the 68 allergic fungal rhinosinusitis cases, only 42 (61.7 per cent) had positive fungal cultures; of the 10 controls, only three (30 per cent) had positive cultures. Species from the dematiaceous family were most commonly grown, being isolated in 30 cases (71.4 per cent). Bipolaris was the most commonly isolated species (18 cases) followed by curvularia (11 cases) and alternaria (one case). Polymerase chain reaction assay detected fungal DNA in all the allergic fungal rhinosinusitis cases and also in four controls (40 per cent). Ten patients (of 68; 14.7 per cent) were positive forAspergillus fumigatusspecific immunoglobulin E. The mean concentration of this immunoglobulin was 11.32 ± 4.12 IU/ml in patients and 0 IU/ml in controls, a statistically significant difference.

Conclusion:

Detection of fungal DNA in nasal aspirate by polymerase chain reaction was superior to fungal cultures as a method of detecting fungal growth. In allergic fungal rhinosinusitis, fungal growth is not always accompanied by an allergic reaction.

Allergic fungal rhinosinusitis with skull base and orbital erosion

Introduction:

Allergic fungal rhinosinusitis is a benign, noninvasive sinus disease related to hypersensitivity to fungal infection having bony skull base and orbital erosion as common finding.

Patients and method:

This descriptive study was conducted at the department of otorhinolaryngology, Dow University of Health Sciences, Karachi, Pakistan, from April 2003 to March 2006. In forty-seven proven cases of allergic fungal sinusitis the following information was recorded: demographic data, signs and symptoms, laboratory investigation results, imaging results, pre- and post-operative medical treatment, surgery performed, follow up, and residual or recurrent disease. The Statistical Package for the Social Sciences version 10.0 software was used for data analysis.

Results:

Findings indicated that allergic fungal rhinosinusitis usually occurred in the second decade of life (51.06 per cent) in males (70.21 per cent), allergic rhinitis (100 per cent) and nasal polyposis (100 per cent). Nasal obstruction (100 per cent), nasal discharge (89.36 per cent), postnasal drip (89.36 per cent), and unilateral nasal and paranasal sinus involvement (59.57 per cent) were significant features. Aspergillus (59.57 per cent) was the most common aetiological agent. Combined orbital and skull base erosion was seen in 30.04 per cent of cases, with male preponderance 6.8:1. Endoscopic sinus surgery was performed in all cases, and recurrent or residual disease was observed in 19.14 per cent.

Conclusion:

Allergic fungal rhinosinusitis is a disease of young, immunocompetent individual. Skull base and orbital erosion are seen in one-third of cases. Bone erosion is 6.8 times more common in males than females. Orbital erosion is 1.5 times more common than skull base erosion. Endoscopic surgical debridement and drainage combined with topical steroids leads to resolution of disease in the majority of cases, without resorting to systemic antifungal agents, craniotomy or dural resection.

[Pathologic findings and main aetiologies of rhinosinusal infections]

A large variety of infectious diseases may involve the rhinosinusal tract. They include bacterial, viral, fungal, and parasite infections. These infections can induce an acute and/or a chronic inflammatory reaction. They can develop both in immunocompetent or in immunodeficient patients. Clinically, the consequences of these infections are variable, but a few of them have to be rapidly diagnosed for an immediate specific treatment. This article describes the pathologic features of a variety of infectious diseases that surgical pathologists may encounter in analysis of biopsy specimens taken from the rhinosinusal tract.

New treatment for invasive fungal sinusitis: three cases of chronic invasive fungal sinusitis treated with surgery and voriconazole

Invasive fungal sinusitis is a relatively rare disease and can be divided into acute fulminant, chronic, and granulomatous invasive fungal sinusitis. The conventional treatment is radical surgery combined with systemic amphotericin B administration, but the poor prognosis and unestablished treatment options require a better therapeutic strategy. We report three cases of chronic invasive fungal sinusitis successfully treated with a combination of surgery and voriconazole, a new antifungal agent, with good responses in all patients. Voriconazole administration could form the basis for a new standard treatment for invasive fungal sinusitis.

Allergic Fungal Rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is one of the more commonly encountered forms of noninvasive fungal rhinosinusitis, seen in immunecompetent individuals. It is caused by a Gell and Coombs Type I, IgE mediated (and possibly Type III) hypersensitivity reaction to an extramucosal fungal antigen. It bears striking similarities to Allergic Broncho Pulmonary Aspergillosis (ABPA), in terms of pathogenesis as well as treatment. It commonly presents as nasal polyposis. Most current treatment protocols for this condition are based on a combined medical and surgical approach. In this article we have recapitulated the history, epidemiology, etiology, clinical features, diagnostic investigations and treatment protocols for this disease.

Fungus balls of the paranasal sinuses: a review

In the past 30 years, thanks in part to the advance of both endoscopic technology and imaging possibilities, the classification, diagnosis, and management of rhinosinusitis caused by fungi have been better defined. These are basically divided into invasive and non-invasive forms based on the presence or absence of microscopic evidence of fungal hyphae within the tissues. Among the non-invasive fungal sinus diseases, fungus ball has been increasingly reported and large published series have allowed better characterization of the disease and the treatment strategies. Fungus ball of the paranasal sinuses is defined as the non-invasive accumulation of dense fungal concrements in sinusal cavities, most often the maxillary sinus. To describe this entity, confusing or misleading terms such as mycetoma, aspergilloma or aspergillosis would be best avoided. Clinical presentation is non-specific and the diagnosis is usually suspected on imaging studies. Surgical treatment, usually through an endonasal endoscopic approach, is curative. In this paper, we review the clinical, radiological, and pathological presentation of the fungus ball of the paranasal sinuses as well as the surgical management with emphasis on the transnasal endoscopic approach.

Allergic fungal sinusitis

Many common chronic inflammatory rhinosinusitis conditions (hypertrophic sinus disease [HSD]) have the histopathological profile of allergic or asthmatic inflammation. Allergic fungal sinusitis (AFS) is both a type of noninvasive fungal rhinosinusitis and a type of HSD. AFS has clinicopathological features that make it similar, but not identical, to allergic bronchopulmonary aspergillosis (ABPA). Allergic mucin is a defined pathological entity occurring in ABPA, AFS, and in the HSD "eosinophilic mucin rhinosinusitis (EMRS)." Diagnosis of AFS requires a careful review of surgical reports, histopathology, and culture results. Treatment includes surgery and aggressive postoperative medical management of allergic inflammatory disease. Prognosis is good with integrated medical-surgical follow-up, but recurrence remains problematic. The association of ABPA, AFS, and HSD with class II genes of the major histocompatibility complex places the initiation of these inflammatory diseases within the context of antigen presentation and the acquired immune response. Pathological immunomanipulation of this response by local microbial superantigens may be a common mechanism for disease pathogenesis. Future research into the molecular biology of these related conditions may offer insight into the pathogenesis of other chronic inflammatory diseases.

Allergic fungal sinusitis

Many common chronic inflammatory rhinosinusitis conditions (hypertrophic sinus disease [HSD]) have the histopathological profile of allergic or asthmatic inflammation. Allergic fungal sinusitis (AFS) is both a type of noninvasive fungal rhinosinusitis and a type of HSD. AFS has clinicopathological features that make it similar, but not identical, to allergic bronchopulmonary aspergillosis (ABPA). Allergic mucin is a defined pathological entity occurring in ABPA, AFS, and in the HSD "eosinophilic mucin rhinosinusitis (EMRS)." Diagnosis of AFS requires a careful review of surgical reports, histopathology, and culture results. Treatment includes surgery and aggressive postoperative medical management of allergic inflammatory disease. Prognosis is good with integrated medical-surgical follow-up, but recurrence remains problematic. The association of ABPA, AFS, and HSD with class II genes of the major histocompatibility complex places the initiation of these inflammatory diseases within the context of antigen presentation and the acquired immune response. Pathological immunomanipulation of this response by local microbial superantigens may be a common mechanism for disease pathogenesis. Future research into the molecular biology of these related conditions may offer insight into the pathogenesis of other chronic inflammatory diseases.

HLA-DQB1 *03 in allergic fungal sinusitis and other chronic hypertrophic rhinosinusitis disorders

BACKGROUND

Many common chronic inflammatory disorders have strong HLA gene associations, particularly with MHC class II. Allergic fungal rhinosinusitis (AFS) and hypertrophic sinus disease (HSD) are chronic sinonasal mucosal inflammatory disorders. Allergic bronchopulmonary aspergillosis, a disorder analogous to AFS, was recently reported to have HLA-MHC class II associations.

OBJECTIVE

We sought to determine whether MHC class II is also associated with AFS and HSD.

METHODS

HLA DNA genotyping was obtained on 44 patients with AFS and 30 patients with HSD (of which 21 were atopic).

RESULTS

Sixty-six percent of patients with AFS carried at least one HLA-DQB1 *03 allele; DQB1 *0301 and DQB1 *0302 were the most frequent allelic variants (odds ratio [OR] vs healthy subjects = 8.22; 95% CI, 4.30-15.73; P < .001; OR vs all patients with HSD = 1.93; 95% CI, 1.09-3.41; P < .01; OR vs atopic patients with HSD = 2.57; 95% CI, 1.46-4.53; P < .001). Of the 31 patients with AFS and positive Bipolaris spicifera cultures, 68% had DQB1 *03, with DQB1 *0301 and DQB1 *0302 being most frequent (OR vs healthy subjects = 8.93; 95% CI, 4.65-17.15; P < .001; OR vs patients with HSD = 2.10; 95% CI, 1.18-3.73; P < .001). Of the 30 patients with HSD, 50% carried DQB1 *03 (OR vs healthy subjects = 4.25; 95% CI, 2.25-8.02; P < .001) but differed in frequencies of DQB1 *03 allelic variants compared with patients with AFS ( P = .0004). For HSD, nonatopic subjects had the highest DQB1 *03 association (OR vs healthy subjects = 8.63; 95% CI, 4.50-16.54; P < .001). DQB1 *03 allelic variants did not correlate with allergy skin test results, atopic status, total serum IgE levels, culture results, asthma, or aspirin-nonsteroidal anti-inflammatory drug hypersensitivity.

CONCLUSION

Patients with AFS and HSD have HLA-DQB1 *03 alleles as a risk factor for disease, with AFS having the highest association. However, they differ in DQB1 *03 allelic variant frequencies, suggesting several potential roles for MHC class II in their immunopathogenesis.

Allergic fungal sinusitis

AFS is an increasingly recognized form of HSD, now reported throughout the world. It is probably the most frequently occurring fungal rhinosinusitis disorder. The term fungal sinusitis is no longer appropriate because the five categories of fungal rhinosinusitis can now be differentiated. Each category of fungal rhinosinusitis disorder carries different treatment approaches and prognosis. Diagnostic error can be minimized by adhering to strict diagnostic criteria. The analogy (but not identity) of AFS to ABPA has been supported by histopathology, immunopathology, and the clinical response to OCS treatment. AFS represents a true medical surgical disorder in which both surgery and postoperative medical treatment, if properly coordinated between medical and surgical specialists, leads to the best patient outcomes. Continued advances in the understanding of the immunogenetics and immunopathogenesis of AFS may provide fundamental insights into molecular mechanisms operant in other chronic inflammatory disorders, including other chronic eosinophilic-lymphocytic respiratory mucosal disorders such as common forms of HSD and chronic severe asthma.

Allergic fungal sinusitis: pathogenesis and management strategies

Allergic fungal sinusitis (AFS) is a noninvasive form of highly recurrent chronic allergic hypertrophic rhinosinusitis that can be distinguished clinically, histopathologically and prognostically from the other forms of chronic fungal rhinosinusitis. There are three invasive (acute necrotising, chronic invasive and granulomatous invasive) and two noninvasive (fungal ball and allergic fungal) forms of fungal rhinosinusitis currently recognised. Confusion in differentiating between the various forms of fungal rhinosinusitis and between other forms of chronic hypertrophic sinus disease (HSD) can be eliminated by adhering to strict diagnostic criteria. Although there are characteristic presenting clinical history and physical examination findings, laboratory test results, including elevated total serum IgE and positive inhalant allergy skin tests, and sinus computed tomography scans showing chronic rhinosinusitis (often with the presence of hyperattenuating sinus contents) diagnosis of AFS is essentially based on histopathology obtained from sinus surgery. Histopathology shows the presence of eosinophilic-lymphocytic sinus mucosal inflammation, extramucosal allergic mucin (that is also seen grossly at surgery as a characteristic 'peanut-buttery' material), and scattered silver stain positive fungal hyphae within the allergic mucin but not in the mucosa. Treatment and follow up of AFS has been based on its immunopathological analogy to allergic bronchopulmonary aspergillosis, a similar noninvasive fungal hypersensitivity disorder of the lung, and its clinical and pathophysiological relationship to other forms of HSD and asthma. Treatment involves aggressive sinus surgery followed by medical management that includes allergen immunotherapy, topical and systemic corticosteroids, antihistamines and antileukotrienes. Total serum IgE levels should be followed postoperatively as they can be prognostic for recurrent disease. Close follow up and coordination of treatment by both medical and surgical physicians as a team leads to the best clinical outcomes. Ongoing studies are being directed at furthering our understanding of the pathophysiological relationships and treatment options for AFS, and other common forms of chronic hypertrophic rhinosinusitis disorders.

Bipolaris spicifera causes fungus balls of the sinuses and triggers polypoid chronic rhinosinusitis in an immunocompetent patient

We report the rare case of a 19-year-old immunocompetent male suffering both from fungus balls of the sinuses and from chronic rhinosinusitis with massive polyposis. Endoscopic sinus surgery revealed grayish brown necrotic masses embedded in viscous eosinophilic mucus. Inoculated onto petri dishes, these masses as well as the mucus grew a dark pigmented fungus, which was identified as Bipolaris spicifera.

Adverse human health effects associated with molds in the indoor environment

Molds are common and important allergens. About 5% of individuals are predicted to have some allergic airway symptoms from molds over their lifetime. However, it should be remembered that molds are not dominant allergens and that the outdoor molds, rather than indoor ones, are the most important. For almost all allergic individuals, the reactions will be limited to rhinitis or asthma; sinusitis may occur secondarily due to obstruction. Rarely do sensitized individuals develop uncommon conditions such as ABPA or AFS. To reduce the risk of developing or exacerbating allergies, mold should not be allowed to grow unchecked indoors. When mold colonization is discovered in the home, school, or office, it should be remediated after the source of the moisture that supports its growth is identified and eliminated. Authoritative guidelines for mold remediation are available. Fungi are rarely significant pathogens for humans. Superficial fungal infections of the skin and nails are relatively common in normal individuals, but those infections are readily treated and generally resolve without complication. Fungal infections of deeper tissues are rare and in general are limited to persons with severely impaired immune systems. The leading pathogenic fungi for persons with nonimpaired immune function, Blastomyces, Coccidioides, Cryptococcus, and Histoplasma, may find their way indoors with outdoor air but normally do not grow or propagate indoors. Due to the ubiquity of fungi in the environment, it is not possible to prevent immunecompromised individuals from being exposed to molds and fungi outside the confines of hospital isolation units. Some molds that propagate indoors may under some conditions produce mycotoxins that can adversely affect living cells and organisms by a variety of mechanisms. Adverse effects of molds and mycotoxins have been recognized for centuries following ingestion of contaminated foods. Occupational diseases are also recognized in association with inhalation exposure to fungi, bacteria, and other organic matter, usually in industrial or agricultural settings. Molds growing indoors are believed by some to cause building-related symptoms. Despite a voluminous literature on the subject, the causal association remains weak and unproven, particularly with respect to causation by mycotoxins. One mold in particular, Stachybotrys chartarum, is blamed for a diverse array of maladies when it is found indoors. Despite its well-known ability to produce mycotoxins under appropriate growth conditions, years of intensive study have failed to establish exposure to S. chartarum in home, school, or office environments as a cause of adverse human health effects. Levels of exposure in the indoor environment, dose-response data in animals, and dose-rate considerations suggest that delivery by the inhalation route of a toxic dose of mycotoxins in the indoor environment is highly unlikely at best, even for the hypothetically most vulnerable subpopulations. Mold spores are present in all indoor environments and cannot be eliminated from them. Normal building materials and furnishings provide ample nutrition for many species of molds, but they can grow and amplify indoors only when there is an adequate supply of moisture. Where mold grows indoors there is an inappropriate source of water that must be corrected before remediation of the mold colonization can succeed. Mold growth in the home, school, or office environment should not be tolerated because mold physically destroys the building materials on which it grows, mold growth is unsightly and may produce offensive odors, and mold is likely to sensitize and produce allergic responses in allergic individuals. Except for persons with severely impaired immune systems, indoor mold is not a source of fungal infections. Current scientific evidence does not support the proposition that human health has been adversely affected by inhaled mycotoxins in home, school, or office environments.

A superantigen hypothesis for the pathogenesis of chronic hypertrophic rhinosinusitis, allergic fungal sinusitis, and related disorders

BACKGROUND

Chronic eosinophilic-lymphocytic respiratory mucosal inflammatory disorders include hypertrophic sinus disease, allergic fungal sinusitis, allergic bronchopulmonary aspergillosis, and chronic severe asthma. They have many analogous or shared aspects of pathology at molecular, cellular, and clinical levels of analysis.

OBJECTIVE

To propose a theory, and supporting data through comprehensive literature review, that unifies these diseases' pathogenesis. METHODS AND DATA SOURCES: Current medical literature was used as supportive background information. Reinterpretation of existing studies and reasoned speculation were used when necessary and identified where used. English language MEDLINE articles that referenced sinusitis, rhinosinusitis, allergic fungal sinusitis, asthma, allergic bronchopulmonary aspergillosis, nasal polyp, superantigen, and T cell receptor from 1983 to present were potentially used as background or supportive information. Additional referenced articles, published abstracts, and National Center for Biotechnology Information Entrez protein database searches were used. Case reports, studies, review articles, and textbooks were included.

RESULTS

Multiple lines of evidence support the proposed hypothesis that microbial T cell superantigen production, persistence, and host-responsiveness are the fundamental components that unify the pathogenesis of all common chronic eosinophilic-lymphocytic respiratory mucosal inflammatory disorders. Superantigen amplification of preexisting immunopathology is the proposed mechanism for disease induction and maintenance. Preexisting immunopathology is created in the individual by a potential heterogeneity of immunopathologic signals that can include type I immediate hypersensitivity, other antigen-specific immune responses, cytokine dysregulation, eicosanoid dysregulation, various genetic mutations, and other molecular pathology. Although the ability to develop chronic severe inflammatory disease is dependent upon this immunopathology, host T cell receptor V beta genetics and persistent superantigen production/exposure at the respiratory mucosa by relevant superantigen-producing extra- or intracellular microbes are postulated to be required. This mechanism for disease pathogenesis may also apply to other disorders. Approaches to prove this theory and its predictions are presented.

CONCLUSIONS

The pathogenesis of all the disorders discussed can be unified through the superantigen hypothesis proposed. Multiple lines of evidence support this hypothesis. How we view these common conditions will change, and new research into pathogenesis and treatment will occur if this proves true.