Endoscopic endonasal resection of a Drechslera hawaiiensis sphenoid fungal ball

Background

Fungal infections should always be considered in difficult-to-treat paranasal sinus conditions. Sphenoid fungal balls are characterized by the presence of dense fungal masses in the sinus cavity without invasion of surrounding tissues. This case emphasizes the importance of accurate terminology and management and also highlights the involvement of rare pathogens such as Drechslera hawaiiensis. Diagnosis is typically based on imaging studies and intraoperative findings. Accurate identification of the pathogen is crucial. Fungal infections of the paranasal sinuses, including fungus balls, can present challenges in diagnosis and treatment. D. hawaiiensis, although infrequent, can cause potential life-threatening infections.

Case Description

We present a 26-year-old non-HIV male patient who presented with nasal symptoms and mild headaches. The patient underwent an endoscopic exploration that revealed a soft, grayish lesion with a buttery consistency. Gross total resection was achieved and the lesion was identified as being caused by D. hawaiiensis; thus, intravenous antifungal treatment was given.

Conclusion

Endoscopic surgery remains the preferred approach for disease control. Considering alternative treatments and exploring novel approaches are essential in managing complex pathologies in neurosurgical practice.

Diversity, Lifestyle, Genomics, and Their Functional Role of Cochliobolus, Bipolaris, and Curvularia Species in Environmental Remediation and Plant Growth Promotion under Biotic and Abiotic Stressors

Cochliobolus, Bipolaris, and Curvularia genera contain various devastating plant pathogens that cause severe crop losses worldwide. The species belonging to these genera also perform a variety of diverse functions, including the remediation of environmental contaminations, beneficial phytohormone production, and maintaining their lifestyle as epiphytes, endophytes, and saprophytes. Recent research has revealed that despite their pathogenic nature, these fungi also play an intriguing role in agriculture. They act as phosphate solubilizers and produce phytohormones, such as indole acetic acid (IAA) and gibberellic acid (GAs), to accelerate the growth of various plants. Some species have also been reported to play a significant role in plant growth promotion during abiotic stresses, such as salinity stress, drought stress, heat stress, and heavy metal stress, as well as act as a biocontrol agent and a potential mycoherbicide. Similarly, these species have been reported in numerous industrial applications to produce different types of secondary metabolites and biotechnological products and possess a variety of biological properties, such as antibacterial, antileishmanial, cytotoxic, phytotoxic, and antioxidant activities. Additionally, some of the species have been utilized in the production of numerous valuable industrial enzymes and biotransformation, which has an impact on the growth of crops all over the world. However, the current literature is dispersed, and some of the key areas, such as taxonomy, phylogeny, genome sequencing, phytohormonal analysis, and diversity, are still being neglected in terms of the elucidation of its mechanisms, plant growth promotion, stress tolerance, and bioremediation. In this review, we highlighted the potential role, function, and diversity of Cochliobolus, Curvularia, and Bipolaris for improved utilization during environmental biotechnology.

First report of Bipolaris sorokiniana leaf spot disease on watermelon (Citrullus lanatus) in Florida

Watermelon is an important crop in Florida, representing $88.2 million in cash receipts in 2015 (USDA/NASS 2017). In April and May 2021, the UF/IFAS Plant Diagnostic Center in Gainesville, Florida received eight diseased watermelon leaf samples from Alachua, Gilcrest, Levy, and Suwannee counties in Florida. Lesions were round to oblong, light gray to tan with reddish brown margins and white to light gray center, and some were coalescing resulting in about 15% disease severity. Symptomatic leaf tissue (0.5 cm2) was surface sterilized in 0.6% sodium hypochlorite for one minute, rinsed with sterile tap water, plated onto water agar media plates, and incubated at 27°C under 12-h light/dark cycle for 7 days. Characteristic Bipolaris conidia with gray to black brownish cottony mycelial growth were consistently found growing from plated lesions. The pathogen was isolated from two of the eight samples using a 0.5 mm diameter sterile metal needle to transfer a single conidium onto DifcoTM Potato Dextrose Agar (PDA) plates. Three isolates were designated G21-562 from Levy and G21-599a and G21-599b from Alachua County. All three isolates produced curved or straight, cylindrical, obclavate, distoseptate brownish gray conidia with 3 to 8 septa, mostly tapering towards ends with dark brownish to black hilum, that ranged from averaged 62um x 25um (n=30, SD=8 for length and 3 for width). Conidiophores were brownish, septate, smooth, and straight, single or in small groups, simple or branched, and swollen at the upper tip. Internal transcribed spacer region (ITS) and partial glyceraldehyde-3-phosphate dehydrogenase (GPDH) gene sequences were amplified using primers ITS1/ITS4 and GPD-1/GPD-2 (Berbee et al. 1999). Reference sequences (Adhikari et al. 2020 and Manamgoda et al. 2014) were aligned using MUSCLE and trimmed to consistent length. Using concatenated sequence alignments of both loci, a maximum likelihood phylogenetic tree was constructed based on K2+G substitution model selected by BIC using Mega X (Kumar et al. 2018) with 1,000 bootstrap. The ITS and GPDG sequences of G21_599b, G21_599a and G21_562 (GenBank accessions OK614094 to 96, OP297398 to 400) showed 100% identity across 888 nucleotides across both loci to B. sorokiniana isolates CBS_110.14 and CBS_ 120.24 and were distinct from other reference isolates. To fulfill Koch's postulates, all three isolates were grown on PDA at 27°C and 12-h light/dark cycle. After a week, conidia were harvested in sterile water, and the conidial suspensions were adjusted to 105 conidia/ml using a hemocytometer. Each conidial suspension and Tween 20 water control was sprayed onto three seedlings of 'Sugar Baby' watermelon until runoff, and inoculated seedlings were sealed in a plastic bag for 24 hrs. The experiment was done in a greenhouse (20- 25°C) and repeated once. After a week of incubation, the same leaf lesion symptoms described above were observed on seedlings inoculated with conidia, whereas seedlings sprayed with the control were asymptomatic. Isolations from symptomatic tissue produced gray to black mycelia with conidia that were the same as described from field samples. To our knowledge, this is the first report of leaf spot on watermelon caused by B. sorokiniana. B. sorokiniana is a common pathogen of grasses and agronomic crops (Farr and Rossman 2020). The extent to which this emerging disease of Florida watermelon may negatively impact production is unknown and should be the subject of future observation and research.

Identification of Early and Extra-Early Maturing Tropical Maize Inbred Lines with Multiple Disease Resistance for Enhanced Maize Production and Productivity in Sub-Saharan Africa

Maize, a staple for millions across sub-Saharan Africa (SSA), faces major biotic constraints affecting production and safety of the crop. These include northern corn leaf blight (NCLB), southern corn leaf blight (SCLB), Curvularia leaf spot (CLS), and aflatoxin contamination by Exserohilum turcicum, Bipolaris maydis, Curvularia lunata, and Aspergillus flavus, respectively. Farmers in SSA would benefit tremendously if high-yielding maize hybrids with multiple disease resistance (MDR) were developed and commercialized. In all, 49 early-maturing (EM; 90 to 95 days to physiological maturity) and 55 extra-early-maturing (EEM, 80 to 85 days to physiological maturity) inbred lines developed by the International Institute of Tropical Agriculture were identified as resistant to NCLB in field evaluations in multiple agroecologies of Nigeria in 2017 and 2018. From each maturity group, the 30 most resistant inbreds were selected for evaluation for resistance to SCLB and CLS using a detached-leaf assay. Additionally, the inbreds were screened for resistance to kernel rot and aflatoxin contamination using a kernel screening assay. In all, 7 EM and 6 EEM maize inbreds were found to be highly resistant to the three foliar pathogens while 10 inbreds were resistant to the foliar pathogens and supported significantly less (P = 0.01) aflatoxin accumulation than other inbreds. Inbreds having MDR should be tested extensively in hybrid combinations and commercialized. Large-scale use of maize hybrids with MDR would (i) increase maize production and productivity and (ii) reduce losses caused by aflatoxin contamination. Overall, planting of EM and EEM maize hybrids with MDR would contribute to food security, reduced aflatoxin exposure, and increased incomes of maize farmers in SSA.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

Effects of Different Types of Additional Fertilizers on Root-associated Microbes of Napa Cabbage Grown in an Andosol Field in Japan

The effects of different types of additional fertilizations (a compound fertilizer and Chiyoda-kasei) on the root-associated microbes of napa cabbage grown in an Andosol field were investigated by molecular community ana-lyses. Most of the closest known species of the bacterial sequences whose relative abundance significantly differed among fertilizers were sensitive to nitrogen fertilization and/or related to the geochemical cycles of nitrogen. The fungal community on the roots of napa cabbage was dominated by two genera, Bipolaris and Olpidium. The relative abundance of these two genera was affected by the types of fertilizers to some extent and showed a strong negative correlation.

Exploring the Skin Mycobiome in Very Preterm babies during the early neonatal period in a Neonatal Intensive Care Unit of India

The neonatal skin microbiome consists of all the genomes and genetic products of micro-organisms harbouring the skin of babies. Host and the microbiota develop a harmonious environment resulting in symbiosis. Any disruption of this environment could lead to pathological disease. Our study was conducted to explore the neonatal skin fungal microbiome of very preterm neonates admitted to Neonatal Intensive Care Unit at a tertiary health care setting using Next Generation Sequencing of the18S rRNA gene. The most abundant genera found in 22/30 samples were Candida followed by Bipolaris & Cladosporium on the skin microbiome of these neonates. The presence of these fungi, whether just as commensals or as potential pathogens, is currently under research, owing to the risk of early exposure and incidence of infection right from birth.

Allergic fungal rhinosinusitis presenting with intracranial spread along large sphenoidal emissary foramen

Abstract

A 13-year-old girl was admitted for headache, right periorbital swelling and erythema. CT imaging demonstrated right orbital preseptal cellulitis, severe pansinusitis and suspected epidural abscess. Brain MRI and sinus CT confirmed an epidural abscess in the right middle cranial fossa and a second extra-cranial abscess in the right infratemporal fossa along with large right sphenoidal emissary foramen. Drainage from sinus surgery confirmed allergic fungal rhinosinusitis. She was treated with prednisone and voriconazole.

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Allergic fungal rhinosinusitis can rarely extend intracranially.

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Sphenoid emissary foramen can act as a potential communication channel between sphenoid sinus and intracranial compartment.

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Emissary vein of Vesalius traverses the sphenoidal emissary foramen.

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Emissary vein of Vesalius connects the pterygoid plexus to the cavernous sinus.

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Allergic fungal rhinosinusitis generates fibrino-purulent material with “peanut butter” appearance.

Bipolaris keratitis following photorefractive keratectomy: Case report

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Photorefractive keratectomy is a common refractive surgery which has excellent outcome in correcting refractive errors.

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This procedure carries the risk of infectious keratitis due to removal of epithelial layer during the procedure.

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Few cases has been reported with fungal keratitis following the procedure.

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In the current case the culture was positive for bipolaris species and the patient showed excellent response to medical treatment.

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Early diagnosis, appropriate laboratory testing, close observation and aggressive antifungal therapy can result in good outcomes.

Introduction

Fungal keratitis is an uncommon condition that can occur after ocular surgery or trauma to the eye. Some cases have been reported after corneal refractive surgery. Most cases of keratitis following refractive surgery are due to gram-positive bacteria. However, there are a few reports in the literature of fungal and protozoal infections.

Case Presentation

A 29-year-old healthy male developed fungal keratitis Five days following photorefractive keratectomy.

Clinical findings and Investigations

The patient was admitted to the hospital, corneal scraping was performed and sent for staining and routine cultures. A corneal swab was also performed and sent for polymerase chain reaction (PCR). On day 10 post-admission, the fungal culture was positive for Bipolaris.

Intervention and Outcome

Intensive topical antifungal drops were started initially then tapered when clinical improvement was evident. The patient had good final outcome with preservation of good vision and free of symptoms six months following the infection.

Relevance and Impact

Fungal keratitis following corneal refractive surgery is rare. However, it is an infection that can potentially lead to poor outcomes if appropriate management is delayed. Therefore, a high index of suspicion is required especially when multiple risk factors is present.

Monitoring and Surveillance of Aerial Mycobiota of Rice Paddy through DNA Metabarcoding and qPCR

The airborne mycobiota has been understudied in comparison with the mycobiota present in other agricultural environments. Traditional, culture-based methods allow the study of a small fraction of the organisms present in the atmosphere, thus missing important information. In this study, the aerial mycobiota in a rice paddy has been examined during the cropping season (from June to September 2016) using qPCRs for two important rice pathogens (Pyricularia oryzae and Bipolaris oryzae) and by using DNA metabarcoding of the fungal ITS region. The metabarcoding results demonstrated a higher alpha diversity (Shannon–Wiener diversity index H′ and total number of observed species) at the beginning of the trial (June), suggesting a higher level of community complexity, compared with the end of the season. The main taxa identified by HTS analysis showed a shift in their relative abundance that drove the cluster separation as a function of time and temperature. The most abundant OTUs corresponded to genera such as Cladosporium, Alternaria, Myrothecium, or Pyricularia. Changes in the mycobiota composition were clearly dependent on the average air temperature with a potential impact on disease development in rice. In parallel, oligotyping analysis was performed to obtain a sub-OTU identification which revealed the presence of several oligotypes of Pyricularia and Bipolaris with relative abundance changing during monitoring.

Identity and Pathogenicity of Fungi Associated with Crown and Root Rot of Dryland Winter Wheat in Azerbaijan

A comprehensive survey was performed to assess fungal populations associated with crown and root rot of wheat throughout the main wheat-growing areas of Azerbaijan. Samples were taken from 76 fields; 630 fungal strains were isolated, identified, and evaluated for pathogenicity. The identification was conducted with morphological and molecular tools such as species-specific PCR and DNA sequencing of the internal transcribed spacer (ITS) and translation elongation factor 1-α (EF1-α) loci. The fungus found in the greatest number of fields (44) was Fusarium culmorum with 192 isolates, followed by F. acuminatum. Other Fusarium spp. isolates were identified: F. equiseti, F. pseudograminearum, F. graminearum, F. incarnatum, F. avenaceum, F. hostae, F. oxysporum, F. proliferatum, F. algeriense, and F. brachygibbosum. Bipolaris sorokiniana, Curvularia spicifera, Exserohilum pedicellatum, Nigrospora oryzae, and Rhizoctonia spp. isolates were also identified, associated with underground parts of wheat. Phylogenetic analyses based on ITS and EF1-α sequences of the isolates showed that the isolates belonging to the same species were clearly separated in the dendrogram. Pathogenicity assays revealed that F. culmorum, F. pseudograminearum, and F. graminearum were most aggressive; F. avenaceum, F. hostae, F. algeriense, B. sorokiniana, C. spicifera, and R. solani isolates were moderately aggressive; C. inaequalis, E. pedicellatum, and N. oryzae were weakly aggressive; and others were nonpathogenic. The result of this study exhibited the existence of a wide range of species associated with crown and root rot of wheat in Azerbaijan. Additionally, this is the first report of F. hostae, F. algeriense, C. spicifera, C. inaequalis, and N. oryzae as pathogens on wheat in Azerbaijan. Azerbaijan is the second country after Algeria in which F. algeriense was detected.

in Sichuan, China

Many species of the genus Bipolaris are important plant pathogens and often cause leaf spot, root rot, and seedling blight in an extremely wide range of hosts around the world. In recent years, maize leaf spot caused by Bipolaris species has frequently occurred with complex symptoms and is becoming increasingly serious in Sichuan Province of China. To investigate the population diversity of Bipolaris spp. and their corresponding symptoms in maize, 747 samples of maize leaf spot were collected from 132 sampling sites in 19 administrative districts of Sichuan Province from 2011 to 2018. Based on morphological characteristics, pathogenicity testing, and phylogenetic analysis of the rDNA internal transcribed spacer (ITS) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes, a total of 1186 Bipolaris isolates were identified as B. maydis, B. zeicola, B. cynodontis, B. oryzae, B. setariae, and B. saccharicola, among which B. maydis and B. zeicola were the dominant pathogenic species, accounting for 57.34% and 42.07% of the isolates, respectively. We found that B. zeicola isolates were mainly distributed in high altitude and cool mountainous areas, while B. maydis was more widely distributed in Sichuan Province. The typical symptoms caused by the Bipolaris species were clearly distinct in maize. The typical symptoms caused by B. maydis were elongated strip lesions, or fusiform, elliptical lesions, and those caused by B. zeicola were narrow linear lesions. Herein, B. saccharicola was first reported on maize and caused subrotund lesions. This study provides useful information for disease diagnosis and management for Bipolaris leaf spot in maize.

Identification and Pathogenicity of Fungal Pathogens Causing Black Point in Wheat on the North China Plain

Fungi associated with black point were isolated from three highly susceptible wheat genotypes in the North China Plain. The 21 isolates represented 11 fungal genera. The most prevalent genera were Alternaria (isolation frequency of 56.7%), Bipolaris (16.1%), and Fusarium (6.0%). The other eight genera were Curvularia, Aspergillus, Cladosporium, Exserohilum, Epicoccum, Nigrospora, Penicillium, and Ulocladium; their isolation frequencies ranged from 0.8 to 4.8%. The pathogenicity of the isolates was individually assessed in the greenhouse by inoculating wheat plants with spore suspensions. Ten of the 21 isolates caused significantly higher incidences of black point than that the controls. These isolates belonged to eight fungal species (A. alternata, B. sorokiniana, B. crotonis, B. cynodontis, C. spicifera, F. equiseti, E. rostratum, and E. sorghinum) based on morphological traits and phylogenetic analysis. The average incidences of black point in the eight fungal species were 32.4, 54.3, 43.0, 41.9, 37.2, 38.8, 50.1, and 34.1%, respectively. B. sorokiniana and A. alternata were determined to be the most important pathogens in the North China Plain based on fungal prevalence and symptom severity. This study is the first to identify E. rostratum as a major pathogen causing black point in wheat.

in an Immunocompetent Patient

Bipolaris is a dematiaceous fungus seen in the skin, nasal sinuses, and occasionally in the central nervous system. We present an immunocompetent female with bilateral dural-based abscesses caused by a Bipolaris species. The patient had no involvement of the sinuses with the fungus but was later found to have a significant Bipolaris infection of her biliary tree.

Cardiothoracic surgical site phaeohyphomycosis caused by Bipolaris mould, multiple US states, 2008-2013: a clinical description

Bipolaris mould surgical site infections (SSIs) are exceedingly rare. We describe 21 cases of Bipolaris SSIs in pediatric and adult cardiothoracic surgery patients at ten hospitals in Texas, Arkansas, and Florida during 2008-2013. Median case-patient age was 55 years (range: 3 days-82 years), and 19 (90%) were male. Ten (48%) had coronary artery bypass or valve surgery, and seven (33%) had heart transplantation. Fifteen (71%) had more than one cardiothoracic procedure (median: 3, range: 1-11). Thirteen (62%) case-patients (all 5 pediatric patients, and 8 (50%) of 16 adult patients) had delayed sternal closure (chest closed >1 day [median = 8 days; range: 2-22] following the initial cardiothoracic procedure). Thirteen (62%) had mediastinitis. Median time from initial surgery to positive Bipolaris culture was 20 days (range: 6-497). Sixteen (76%) case-patients died.

Molecular identification and antifungal susceptibility of Curvularia australiensis, C. hawaiiensis and C. spicifera isolated from human eye infections

A reliable identification method was developed for three closely related Curvularia species, which are frequently isolated from human keratomycoses. Since the traditionally used morphological method and the increasingly used internal transcribed spacer (ITS)-based molecular method proved to be insufficient to discern C. australiensis, C. hawaiiensis and C. spicifera, other molecular targets, such as β-tubulin, translation elongation factor 1-α and the nuclear ribosomal intergenic spacer (IGS), were tested. Among them, the use of the highly divergent IGS sequence is suggested and the species-specific discriminating characters were determined in appropriate reference strains. It was also concluded that C. hawaiiensis and C. spicifera can be predominantly isolated from eye infections among the three species. The in vitro antifungal susceptibility of 10 currently used antifungal agents against 32 Curvularia isolates was also investigated. MICs were determined in each case. Isolates of C. spicifera proved to be less susceptible to the tested antifungals than those of C. hawaiiensis, which underline the importance of the correct identification of these species.

Unilateral renal phaeohyphomycosis due to Bipolaris spicifera in an immunocompetent child - rare case presentation and review of literature

Phaeohyphomycosis refers to infections caused by phaeoid fungi that can have an aggressive course in normal hosts. We report a case of left-sided renal phaeohyphomycosis due to Bipolaris spicifera in a 7-year-old immunocompetent male child. He presented with fever, dysuria, nausea, vomiting and flank pain. Examination revealed tenderness at the left costovertebral angle. Histological examination and culture of biopsy from left kidney and blood yielded the fungal pathogen Bipolaris spicifera. His past history revealed that he was diagnosed perinatally with bilateral hydronephrosis due to bilateral pelvic ureteric junction obstruction. He underwent an open dismembered pyeloplasty on the left side followed by the right side pyeloplasty at the age of 6 months and 1.5 years respectively. He was on a regular follow-up for 5 years and had been doing well. Now he was diagnosed as a case of unilateral renal phaeohyphomycosis. The patient was managed successfully with antifungal drugs amphotericin B and itraconazole. A review of previously reported bipolaris cases with their clinical manifestations, treatment and outcome is presented. Renal phaeohyphomycosis remains an unusual disease. Aggressive diagnostic approaches and careful management helped in survival of the patient.

Novel Curvularia species from clinical specimens

The fungal genus Curvularia includes numerous plant pathogens and some emerging opportunistic pathogens of humans. In a previous study we used morphology and sequences of the nuclear ribosomal internal transcribed spacer region (ITS) and the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene to identify species within a set of 99 clinical Curvularia isolates from the USA. Seventy-two isolates could be identified while the remaining 27 isolates belonged in three unclassified clades that were tentatively labelled Curvularia sp. I, II and III. In the present study, we further assess the taxonomic placement of these isolates using sequences of ITS, gpd, the large subunit rDNA, and the second largest subunit of RNA polymerase II. DNA sequence comparisons with a set of 87 isolates representing 33 Curvularia spp. and members of the closely-related genera Bipolaris and Exserohilum revealed that Curvularia sp. I, II and III represent novel lineages in Curvularia. These lineages are morphologically different from the currently accepted species. In the phylogenetic tree, Curvularia sp. I and sp. III were each split into two distinct lineages. Morphology and phylogeny supported the proposal of five new species, to be named C. americana, C. chlamydospora, C. hominis, C. muehlenbeckiae and C. pseudolunata. The concatenated 4-locus phylogeny revealed the existence of six clades in Curvularia, which are associated with particular morphological features. They were named after representative species, namely americana, eragrostidis, hominis, lunata, spicifera and trifolii.

Virulence of Curvularia in a murine model

We have evaluated the virulence of two clinically relevant species of Curvularia; Curvularia spicifera and C. hawaiiensis, using an experimental model of disseminated infection in immunocompromised mice. Several inocula were tested over a range 1 × 10(3) -1 × 10(6) colony-forming units/animal. Both species had a similar behaviour, producing a high mortality. Tissue burden and histopathology studies demonstrated that lung was the organ most affected.

Allergic fungal rhinosinusitis: a review

BACKGROUND

Allergic fungal rhinosinusitis (AFRS) is a relatively new and incompletely understood clinical entity with characteristic clinical, radiographic, and histopathologic findings. AFRS is often misdiagnosed. Recognition and understanding of this unique disease will lead to efficient diagnosis and treatment of this curable process.

METHODS

The following is a review, conducted via a PubMed English language search, of the current diagnosis, pathogenesis, and treatment of AFRS.

RESULTS

AFRS is an immune-modulated disease entity. The Bent and Kuhn diagnostic criteria are the standard for diagnosis of this disease that occurs because of an incompletely understood allergic mechanism. Multimodality treatment relies heavily on surgical therapy along with corticosteroid use and immunotherapy.

CONCLUSIONS

AFRS is a unique disease process that differs from other forms of sinusitis and as such requires that physicians understand its diagnosis and management to provide care for patients with this condition.