Allergic fungal sinusitis in the southeastern USA: involvement of a new agentEpicoccum nigrumEhrenb. ex Schlecht. 1824

Fungal Sensitization and Human Allergic Disease

PURPOSE OF THE REVIEW

Fungal sensitizations have been associated with hypersensitivity reactions with variable levels of evidence available to link types of fungi with human disease. We conducted systematic reviews of the literature to identify the strength of evidence linking lesser-studied fungi for which there are commercially available extracts to identify populations in which they were useful in clinical practice.

RECENT FINDINGS

Excluding five fungi for which hundreds of articles were identified, there are 54 articles on the remaining fungi with clinical data. For 12 of the fungi, the prevalence of fungal sensitization varies in different hypersensitivity disorders due to factors related to geographic areas, age, and other underlying medical conditions. There were no studies linking seven genera to human disease. Most of the commercially available fungal extracts are uncommonly associated with hypersensitivity reactions in humans. Specific extracts may be useful in particular disease states such as allergic fungal sinusitis or allergic bronchopulmonary mycosis, or when routine testing fails to identify a cause of uncontrolled disease, such as in asthma.

Dematiaceous fungal infections: clinical and pathologic conundrums

Dematiaceous fungi are defined by pigment within their cell walls. They are increasingly recognised human pathogens, causing a wide range of clinical presentations, from localised subcutaneous infections to disseminated disease in rare cases. We report our institutional experience with diagnosis of dematiaceous fungal infections from 2005 to 2022 and highlight four instructive cases that clinically and pathologically mimicked other diseases for which the diagnosis was confirmed by fungal culture (one case) or supported by PCR with 28S rRNA and internal transcribed spacer primers (three cases). Two patients were immunocompromised and two had presumed exposure to the organism. In each highlighted case, fungal infection was not clinically suspected, and the pathologist was critical in making the diagnosis and ensuring appropriate clinical management, which was supplemented by fungal stains and novel molecular methods.

Epicoccum sp. as the causative agent of a reddish-brown spot defect on the surface of a hard cheese made of raw ewe milk

Colour defects can affect the appearance of cheese, its flavour, the safety of its consumption, and the price it can demand. This work reports the identification of five fungal isolates from a dairy plant where the surface of most cheeses was affected by patent, reddish-to-brown stains. One of these isolates was obtained from cheese, two from brine, and two from a bulk tank containing ewe milk. Molecular identification by partial amplification, sequencing, and database comparison of the concatenated sequence of the genes coding for the largest subunit of RNA polymerase II (RPB2), β-tubulin (β-TUB), and the large subunit of the rRNA molecule (LSU), plus the internal transcribed sequence (ITS) regions, assigned the isolates to Epicoccum layuense, Epicoccum italicum, and Epicoccum mezzettii. Features of the growth of these different species on different agar-based media, and of the morphology of their conidia following sporulation, are also reported. The strain isolated from cheese, E. layuense IPLA 35011, was able to recreate the reddish-brown stains on slices of Gouda-like cheese, which linked the fungus with the colour defect. In addition, two other strains, E. italicum IPLA 35013 from brine and E. italicum IPLA 35014 from milk, also produced stains on cheese slices. Epicoccum species are widely recognized as plant pathogens but have seldom been reported in the dairy setting, and never as human or animal pathogens.

Associations of observed home dampness and mold with the fungal and bacterial dust microbiomes

The objective of this analysis was to examine and compare quantitative metrics of observed dampness and mold, including visible mold and moisture damage, and fungal and bacterial microbiomes. In-home visits were conducted at age 7 for children enrolled in the Cincinnati Childhood Allergy and Air Pollution Study. Trained study staff evaluated the primary residence and measured total areas of visible moisture and mold damage in the home. Floor dust was collected and archived. Archived dust samples collected from each home (n = 178) were extracted and analyzed using bacterial (16S rRNA gene) and fungal (internal transcribed spacer region) sequencing. Fungi were also divided into moisture requirement categories of xerophiles, mesophiles, and hydrophiles. Data analyses used Spearman's correlation, Kruskal-Wallis, Permanova, DESeq, and negative binomial regression models. Comparing high moisture or mold damage to no damage, five fungal species and two bacterial species had higher concentrations (absolute abundance) and six fungal species and three bacterial species had lower concentrations. Hydrophilic and mesophilic fungi showed significant dose-related increases with increasing moisture damage and mold damage, respectively. When comparing alpha or beta diversity of fungi and bacteria across mold and moisture damage levels, no significant associations or differences were found. Mold and moisture damage did not affect diversity of fungal and bacterial microbiomes. Instead, both kinds of damage were associated with changes in species composition of both bacterial and fungal microbiomes, indicating that fungal and bacterial communities in the home might be influenced by one another as well as by mold or moisture in the home.

Mold burden in house dust and its relationship with asthma control

OBJECTIVE

Some evidences indicate that exposure to molds or their products can be relevant for the loss of asthma control. Thus, we measured the mold burden present inside houses of subjects with asthma, and evaluated its relationship with asthma control.

METHODS

Markers of asthma control in adult patients residing in Mexico City were evaluated through questionnaires and spirometry. Dust was collected from the patients' houses and its fungal content was determined by mold specific quantitative PCR (MSQPCR) for 36 fungal species.

RESULTS

Forty-two patients with asthma (12 males, 30 females) with a mean age of 45 years (18-76 years) were included in the study. The level of asthma control measured through the Asthma Control Test ranged from 9 to 25 (mean 20.9). The FEV₁/FVC ratio fluctuated from 38 to 106 %predicted (mean, 87.4 %predicted). Associations between mold burden and asthma control differed between males and females. Thus, concentrations of some molds, particularly Aspergillus fumigatus, Aureobasidium pullulans, Stachybotrys chartarum, Alternaria alternata, Cladosporium cladosporioides 2, Cladosporium herbarum, and Epicoccum nigrum, were negatively associated with parameters of asthma control in male subjects, but not in female patients.

CONCLUSION

Our results showed that potential indoor exposure to some molds is associated with less asthma control in male subjects.

Fungi Isolated From House Flies (Diptera: Muscidae) on Penned Cattle in South Texas

Musca domestica L. were collected from cattle diagnosed with bovine ringworm to evaluate the potential of the house fly to disseminate Trichophyton verrucosum E. Bodin, a fungal dermatophyte that is the causative agent for ringworm in cattle. Fungal isolates were cultured from 45 individual flies on supplemented Sabouraud dextrose agar, and isolates were identified using morphological and microscopic approaches. Each isolate was identified further by PCR amplification of the ribosomal DNA locus with fungal-specific primers and subsequent amplicon sequencing. Trichophyton verrucosum was not identified using these approaches. However, 35 different fungal species representing 17 genera were cultured from collected flies, including several species that are allergenic and pathogenic to humans and animals. Several species within the fungal orders Hypocreales, Microascales, Onygenales, Saccharomycetales, Xylaniales, and Agaricales were observed for the first time on house flies. The most frequent fungus recovered was Cladosporium cladosporoides Fresen, which is known to be a ubiquitous, airborne allergen to humans.

Advances in Microbiology, Infectious Diseases and Public Health: Fungal Occurrence in the Hair and Skin of Symptomatic Pets in Turin, Italy

Companion animals, often asymptomatic reservoir of fungi, can be important sources of infection in humans, due to the close contact with their owners. The present study was aimed to assess the occurrence of dermatophytes and other fungi isolated from pet dermatological lesions in Turin, Italy. Dermatological specimens were examined for fungal elements by direct microscopy and cultured to detect dermatophytes, other filamentous fungi and yeasts: 247 pets (118 cats, 111 dogs and 18 dwarf rabbits) were positive for fungal detection in culture. Microsporum canis was the most frequent dermatophyte in cats and dogs, whereas Trichophyton mentagrophytes was the most common in rabbits. Among the other fungi, for all examined pets, dematiaceous fungi were the most isolated, followed by Mucorales, penicilli, yeasts and yeast-like fungi, and aspergilli. No gender predisposition was detected for dermatophyte growth; on the contrary, for the other fungi male cats were more susceptible than female. The highest fungal occurrence was recorded in <1-year-old cats for dermatophytes, and in <5-year-old cats and dogs for the other fungi. Autumn was the period associated with a relevant incidence of fungal infection. Finally, fungi were more frequent in non pure-breed cats and in pure-breed dogs. These data underline the importance to timely inform pet owners about the potential health risk of infection caused not only by dermatophytes but also by non-dermatophyte fungi, routinely considered to be contaminants or harmless colonizers, since their role as source of zoonotic infections is not to be excluded.

Taxonomy of Allergenic Fungi

The Kingdom Fungi contains diverse eukaryotic organisms including yeasts, molds, mushrooms, bracket fungi, plant rusts, smuts, and puffballs. Fungi have a complex metabolism that differs from animals and plants. They secrete enzymes into their surroundings and absorb the breakdown products of enzyme action. Some of these enzymes are well-known allergens. The phylogenetic relationships among fungi were unclear until recently because classification was based on the sexual state morphology. Fungi lacking an obvious sexual stage were assigned to the artificial, now-obsolete category, "Deuteromycetes" or "Fungi Imperfecti." During the last 20 years, DNA sequencing has resolved 8 fungal phyla, 3 of which contain most genera associated with important aeroallergens: Zygomycota, Ascomycota, and Basidiomycota. Advances in fungal classification have required name changes for some familiar taxa. Because of regulatory constraints, many fungal allergen extracts retain obsolete names. A major benefit from this reorganization is that specific immunoglobulin E (IgE) levels in individuals sensitized to fungi appear to closely match fungal phylogenetic relationships. This close relationship between molecular fungal systematics and IgE sensitization provides an opportunity to systematically look at cross-reactivity and permits representatives from each taxon to serve as a proxy for IgE to the group.

Unusual causes of fungal rhinosinusitis: a study from a tertiary care centre in South India

PURPOSE

The frequency of mycotic infections of the nose and paranasal sinuses has been increasing over the past three decades. Apart from the common causes of fungal rhinosinusitis such as Aspergillus species and Penicillium species, there have been reports of rare and unusual fungi isolated from India and other countries.

OBJECTIVE

The objective of this study is to find out the prevalence of fungal infections of the nose and paranasal sinuses caused by unusual fungal isolates at a tertiary care teaching hospital in South India.

MATERIALS AND METHODS

Duration of the study period was from April 2009 to March 2010. Specimens were collected from the nose and paranasal sinuses of all clinically and radiologically diagnosed cases of rhinosinusitis. All the clinical specimens were processed by standard methods for fungal culture. This included initial screening by 10% potassium hydroxide, inoculation of the specimen onto Sabouraud dextrose agar and incubation at 25°C and 37°C, followed by slide culture and other special techniques wherever necessary. Histopathological examination was also performed for the specimens.

RESULTS

A total of 60 specimens were received for fungal culture from cases of rhinosinusitis during the period, out of which 45 showed no growth. There were nine cases of Aspergillus flavus, 1 each of Aspergillus fumigatus and Penicillium species. The rest four specimens grew rare fungal isolates, i.e. Acremonium sp., Scedosporium apiospermun, Cladosporium cladosporioides and Lasiodiplodia theobromae. Histopathological findings were also positive for these four cases.

CONCLUSION

Apart from the common causes, unusual fungal pathogens were isolated from cases of rhinosinusitis during the study period, which is in accordance with similar reports from other parts of India and some other countries.

A case of allergic fungal rhinosinusitis due to Ceratocystis adiposa

Ceratocystis adiposa known as phytopathogen of conifers has not been recognized so far as a human pathogen. Herein, we report for the first time a case of allergic fungal rhinosinusitis due to C. adiposa. The fungus was identified by sequencing internal transcribed spacer of rDNA and D1/D2 of larger subunit region.

Impact of fungal load on diagnosis and outcome of allergic fungal rhinosinusitis

Fungal load colonization may modify the classic eosinophilic inflammation in allergic fungal rhinosinusitis (AFRS). We aimed to evaluate the impact of fungal load on diagnosis and outcome of AFRS. In the present cohort study fungal load differences were determined prospectively according to Gomori methenamine silver (GMS) fungal stained (histopathological and cytological examination) with the tenacious mucus, cheesy clay-like materials and sinus mucosa/polyps in 12 AFRS patients. Two groups with different fungal loads, AFRS with (six patients) and without (six patients) high fungal loads (HFL) were evaluated for nasal endoscopic score, paranasal sinuses CT score, histopathological and immunohistochemical changes. Endoscopic outcome scoring differences were evaluated for 1 year after endoscopic sinus surgery and 1 month oral corticosteroids treatment. No differences were observed between both groups (AFRS with/without HFL) concerning the total CT score and opacification features (P > 0.05). Eosinophils and CD3 + CD8 + T cell were dominant in both groups. More edema and less fibrosis were observed in HFL group. Gliotoxin producers Aspergilli were present in all HFL in comparison to 5/6 (83.3%) in cases without HFL. Fewer patients 1/6 (16.6%) and less number of recurrences/year 0.1 ± 0.4 occurred in the AFRS with HFL compared to the AFRS without HFL [5/6 (83.3%) and 1.16 ± 0.7) (P = 0.021 and 0.023, respectively]. In addition to mucus and mucosal tissues, cheesy clay-like materials must be assessed in AFRS cases. Although patients of AFRS with HFL had negligible clinical differences from ordinary AFRS without HFL, they had better outcome after treatment.

Particle-size distributions and seasonal diversity of allergenic and pathogenic fungi in outdoor air

Fungi are ubiquitous in outdoor air, and their concentration, aerodynamic diameters and taxonomic composition have potentially important implications for human health. Although exposure to fungal allergens is considered a strong risk factor for asthma prevalence and severity, limitations in tracking fungal diversity in air have thus far prevented a clear understanding of their human pathogenic properties. This study used a cascade impactor for sampling, and quantitative real-time PCR plus 454 pyrosequencing for analysis to investigate seasonal, size-resolved fungal communities in outdoor air in an urban setting in the northeastern United States. From the 20 libraries produced with an average of ∼800 internal transcribed spacer (ITS) sequences (total 15 326 reads), 12 864 and 11 280 sequences were determined to the genus and species levels, respectively, and 558 different genera and 1172 different species were identified, including allergens and infectious pathogens. These analyses revealed strong relationships between fungal aerodynamic diameters and features of taxonomic compositions. The relative abundance of airborne allergenic fungi ranged from 2.8% to 10.7% of total airborne fungal taxa, peaked in the fall, and increased with increasing aerodynamic diameter. Fungi that can cause invasive fungal infections peaked in the spring, comprised 0.1-1.6% of fungal taxa and typically increased in relative abundance with decreasing aerodynamic diameter. Atmospheric fungal ecology is a strong function of aerodynamic diameter, whereby through physical processes, the size influences the diversity of airborne fungi that deposit in human airways and the efficiencies with which specific groups of fungi partition from outdoor air to indoor environments.

Melanized fungi in human disease

Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes, including chromoblastomycosis, mycetoma, and phaeohyphomycosis. [corrected]. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections.

Epidemiology and Medical Mycology of Fungal Rhinosinusitis

Fungal rhinosinusitis (FRS) refers to a spectrum of disease ranging from benign colonization of the nose and sinuses by pathogenic fungi to acute invasive and fatal inflammation extending to the orbit and brain. FRS is classified into two categories: invasive and noninvasive. Invasive FRS may again be subcategorized into acute invasive (fulminant) FRS, granulomatous invasive FRS, and chronic invasive FRS; while noninvasive FRS is subcategorized into localized fungal colonization, sinus fungal ball and eosinophil related FRS (including allergic fungal rhinosinusitis, eosinophilic fungal rhinosinusitis). This classification is not without controversies, and intermediate and semi-invasive forms may also exist in particular patients. Acute invasive FRS is an increasingly common disease worldwide among the immunocompromised patients and caused most frequently by Rhizopus oryzae, and Aspergillus spp. Granulomatous invasive FRS has mostly been reported from Sudan, India, and Pakistan and is characterized by noncaseating granuloma formation, vascular proliferation, vasculitis, perivascular fibrosis, sparse hyphae in tissue, and isolation of A. flavus from sinus contents. Chronic invasive FRS is an emerging entity occurring commonly in diabetics and patients on corticosteroid therapy, and is characterized by dense accumulation of hyphae, occasional presence of vascular invasion, sparse inflammatory reaction, involvement of local structures, and isolation of A. fumigatus. While localized fungal colonization describes the most benign of all fungal sinusitis in the superficial nasal crusts, sinus fungal ball is a dense mycetoma like aggregate of fungal hyphae in diseased sinuses. Common in southern Europe, especially France, majority of them are sterile on culture while 30-50% may yield Aspergillus spp. The definitions and pathogenesis of the group of syndromes in eosinophil related FRS (AFRS, EFRS) are contentious and a matter of intense research among otolaryngologists, pathologists, immunologists and microbiologists. While dematiaceous fungi are the foremost initiators of these syndromes in the west, Aspergillus flavus is the predominant pathogen in India and the Middle-East.

Fusarium keratitis and contact lens wear: facts and speculations

Over the past several decades mycotic keratitis has been considered a rare sequel to hydrogel contact lens wear. In 2005--2006 an upswing in the incidence of Fusarium keratitis was associated with a disproportionate use of one multipurpose contact lens solution (MPS, ReNu with MoistureLoc, Bausch & Lomb, Rochester, NY). The MPS, as manufactured and marketed, was sterile and met regulatory guidelines for antimicrobial activity. A multivariant interaction of poor hygienic practices and the contact lens paraphernalia were associated with a mostly selective contamination in or on the lens storage case by members of the F. solani/F. oxysporum species complexes from the environment of the user. A decline of the anti-fusaria properties of the MPS in the lens case appeared related to its dissociation from drying, or dilution and the potential for sorption of antimicrobial solution components (e.g., alexidine) to various hydrogel lenses. These factors and capacities of the fusaria for rapid amplification by microcycle conidiation, production of dormant resistant cells, and potential for attachment and penetration of hydrogel lenses, were linked to the occasional selective fungal survival and growth during storage of the lens in MPS. Lack of a manual rubbing-cleaning step in the MPS disinfection process was considered a risk factor for keratitis.

Role of Glycoproteins Isolated from Epicoccum purpurascens in Host-Pathogen Interaction

OBJECTIVE

Attachment to host matrix is an important provisory step for the institution of any fungal infection. The present study investigates the role of glycoproteins of Epicoccum purpurascens in host-fungal adherence.

METHODS

Epicoccum spore-mycelial extract was fractionated on a concanavalin A-Sepharose column. Three glycoproteins of 12, 17 and 33 kDa (Epi p 1) were electroeluted and checked for hemagglutination and hemagglutination inhibition. The monosaccharide content of the highly potent protein Epi p 1 was determined by high-performance anion exchange chromatography and pulsed amperometric detection. The interaction of Epi p 1 with mannose-binding lectin (MBL) leading to the activation of the complement system was studied by immunoblot, ELISA and ELISA inhibition techniques. Immunoblot and immunoblot inhibition were carried out with culture filtrate to determine the nature of Epi p 1.

RESULTS

33 (Epi p 1)-, 17- and 12-kDa proteins were 58, 46 and 38 times more potent than crude extract in hemagglutination activity (HA). The HA of Epi p 1 was inhibited by N-acetyl glucosamine, glucose and laminin. Epi p 1 had a high mannose content, showed MBL binding in ion-dependent manner and caused complement activation. The protein was detected in culture filtrate and thus seems to play a significant role in fungal invasion.

CONCLUSION

Epi p 1, an allergenic glycoprotein of E. purpurascens, is involved in host-fungal interactions through MBL.

Ultrastructure of sporodochium and conidium development in the anamorphic fungus Epicoccum nigrum

Scanning and transmission electron microscopy were used to examine sporodochium and conidium development in Epicoccum nigrum Link. Each sporodochium, a slightly raised mass of hyphae consisting of a pseudoparenchymous stroma covered with muriform conidia, arose from a group of loosely packed hyphae that formed on the agar surface. Conidiophores developed from the surface of the stroma. Each possessed a two-layered wall consisting of an inner electron transparent layer and an outer electron dense layer. Most conidiophores consisted of only two cells, the apical of which became swollen and gave rise to a solitary conidium initial in a holoblastic fashion. This initial enlarged and became divided into a smaller basal cell and a larger apical cell by a transverse septum. While the basal cell did not divide further, the apical cell became divided into numerous cells as the result of the formation of longitudinal and transverse septa. As a conidium matured the electron transparent inner layer of its wall thickened while the surface of its electron dense outer wall layer became transformed into small wart-like surface ornaments. Conidium secession was schizolytic and involved a transverse splitting of the septum separating the basal cell of a conidium from its conidiophore. The end of the basal cell and the tip of the conidiophore became rounded off during conidium secession.

Does the triad of fungi, bacteria and exposure to moisture have an impact on chronic hyperplastic sinusitis?

Here we evaluated a possible relationship between chronic hyperplastic sinusitis (CHS) and moisture exposure and secondly a seasonal variation of fungal and bacterial findings in the healthy nose. In 28 CHS patients sinus mucus was collected during endoscopic sinus surgery. Samples from the nasal cavities of 19 healthy volunteers were collected by nasal lavage (NAL) in January and in September. Bacterial culture and fungal staining and culture were carried out. Histological samples from the sinus mucosa were obtained. Patients' medical history and environmental factors were enquired. Mold odor or moisture problems in the home or work environment were reported by 46% of the CHS patients. Patients who reported moisture exposure did not differ significantly from those who had not been exposed with regards to microbiological findings, tissue eosinophilia, and earlier operations. Cladosporium (16%) and Alternaria (11%) were found in NAL fluid collected in the autumn from the control subjects. No fungi were isolated from samples taken during the winter. An association between CHS or fungal sinusitis and moisture damage was not apparent in the present study. The fungal findings in the nasal cavity reflect the environmental exposure. This should be taken into account when NAL is used for microbiological studies.

PRACTICAL IMPLICATIONS

Living in a moldy house or working in a similar environment may increase the risk of respiratory symptoms and infections. However, our results suggest that chronic hyperplastic sinusitis and fungal sinusitis are not associated with moisture exposure. The nose is a good collector of particles in the air. Especially samples taken by the nasal lavage method reflect the environmental exposure. This should be taken into account when this method is used for microbiological studies.

Epi p 1, an allergenic glycoprotein ofEpicoccum purpurascensis a serine protease

Epicoccum purpurascens (EP) is a ubiquitous saprophytic mould, the inhalant spores and mycelia of which are responsible for respiratory allergic disorders in 5-7% of population worldwide. The diagnosis/therapy of these disorders caused by fungi involves the use of standardized and purified fungal extracts. A 33.5 kDa glycoprotein, Epi p 1 released histamine from whole blood cells of EP allergic patients at a concentration of 50-ng protein. The high specific IgE values detected in EP hypersensitive sera indicated that Epi p 1 is capable of mediating type I hypersensitive reaction in predisposed individuals. It also showed protease activity by virtue of its dose dependent cleavage of serine protease specific synthetic substrate, N-benzoyl arginine ethyl ester hydrochloride (BAEE). The serine protease nature of Epi p 1 was confirmed by its N-terminal sequence (ADG/FIVAVELD/STY) homology to a subtilisin like serine protease. The protease activity of Epi p 1 may be responsible for making its way into the system of pre-disposed individuals through epithelial cell detachment and the histamine releasing ability by cross-linking of IgE antibodies on cell surface is the cause of its allergenic nature.

Allergic fungal sinusitis: report of 3 cases and review of the literature

Allergic fungal sinusitis is a form of noninvasive fungal disease resulting from an IgE-mediated hypersensitivity reaction in atopic individuals. Allergic fungal sinusitis can present with a continuum of symptoms. Accumulation of allergic inspissated mucin may cause simple nasal obstruction or progress to facial deformity with osteolytic destruction and intracranial extension. Multiple species of fungi are now recognized as etiologic factors responsible for initiating the inflammatory response. This article discusses 3 cases involving Aspergillus and Curvularia species, and reviews diagnostic image findings, pathophysiology, and medical-surgical management of this increasingly common disease.

Allergic fungal sinusitis: diagnosis and treatment

Since allergic fungal sinusitis was initially described by Millar in 1981, many have tried to define and explain the disorder. It has been labeled as the sinonasal equivalent of allergic bronchopulmonary aspergillosis; however, allergic fungal sinusitis cannot be categorized so easily. According to the literature at this time, there are five major criteria and six associated characteristics or minor criteria of patients with allergic fungal sinusitis. In reality, patients may not develop all five major criteria or have any of the associated criteria for years. Allergic fungal sinusitis is not only difficult to diagnose, but it is one of the most complicated conditions rhinologists must manage. Endoscopic sinus surgery must be used in conjunction with long-term medical therapy, oral and nasal corticosteroids, immunotherapy, antifungal therapy, and antimicrobial agents to effectively control the problem. Allergic fungal sinusitis is most likely the endpoint in a spectrum of sinonasal disease, driven by the presence of fungus and eosinophils with their inflammatory mediators. The affected nasal mucosa no longer functions properly, and a cycle of chronic edema, stasis, and bacterial superinfection results. Therapy entails disrupting the inflammatory process to allow normal mucosal function to resume.

Effect of ultraviolet germicidal lights installed in office ventilation systems on workers' health and wellbeing: double-blind multiple crossover trial

BACKGROUND

Workers in modern office buildings frequently have unexplained work-related symptoms or combinations of symptoms. We assessed whether ultraviolet germicidal irradiation (UVGI) of drip pans and cooling coils within ventilation systems of office buildings would reduce microbial contamination, and thus occupants' work-related symptoms.

METHODS

We undertook a double blind, multiple crossover trial of 771 participants. In office buildings in Montreal, Canada, UVGI was alternately off for 12 weeks, then turned on for 4 weeks. We did this three times with UVGI on and three times with it off, for 48 consecutive weeks. Primary outcomes of self-reported work-related symptoms, and secondary outcomes of endotoxin and viable microbial concentrations in air and on surfaces, and other environmental covariates were measured six times.

FINDINGS

Operation of UVGI resulted in 99% (95% CI 67-100) reduction of microbial and endotoxin concentrations on irradiated surfaces within the ventilation systems. 771 participants appeared to remain masked, and reported no adverse effects. On the basis of within-person estimates, use of UVGI was associated with significantly fewer work-related symptoms overall (adjusted odds ratio 0.8 [95% CI 0.7-0.99]), as well as respiratory (0.6 [0.4-0.9]) and mucosal (0.7 [0.6-0.9]) symptoms than was non-use. Reduction of work-related mucosal symptoms was greatest among atopic workers (0.6 [0.5-0.8]), and never-smokers (0.7 [0.5-0.9]). With UVGI on, never-smokers also had large reduction of work-related respiratory (0.4 [0.2-0.9]), and musculoskeletal symptoms (0.5 [0.3-0.9]).

INTERPRETATION

Installation of UGVI in most North American offices could resolve work-related symptoms in about 4 million employees, caused by microbial contamination of heating, ventilation, and air-conditioning systems. The cost of UVGI installation could in the long run prove cost-effective compared with the yearly losses from absence because of building-related illness.

Fungal biodiversity--as found in nasal mucus

The biodiversity of fungi isolated from the nasal mucus of patients suffering from chronic rhinosinusitis and from healthy persons was monitored over 28 months. Mucus samples were obtained by flushing the noses of patients with saline or by endoscopic sinus surgery. Fungi from mucus were cultivated on agar plates. Identification was performed microscopically and by polymerase chain reaction with subsequent sequencing of the ribosomal internal transcribed spacer region. Altogether, 619 strains of fungi were cultivated from 233 subjects. Eighty-one species were identified, with a maximum of nine different species per person. The most prevalent isolates belonged to the genera Penicillium, Aspergillus, Cladosporium, Alternaria and Aureobasidium. Whereas Aspergillus and Penicillium spp. occurred in more or less the same numbers throughout the year, Cladosporium spp., Alternaria spp. and Aureobasidium pullulans showed a significantly higher occurrence during late summer and early autumn.

Identification and incidence of fungal strains in chronic rhinosinusitis patients

The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-medicated hypersensitivity to fungal allergens could not be proven in our patients.

Antigenic and allergenic cross-reactivity of Epicoccum nigrum with other fungi

BACKGROUND

Previous studies have identified Epicoccum nigrum (EN) as an important aeroallergen. Shared allergenicity among some fungi responsible for type I allergic disorders has been reported.

OBJECTIVE

To study the cross-reactivity among different fungi and to identify immunoglobulin (Ig)G and IgE binding components shared between EN and 10 other fungi known to cause respiratory allergy.

METHODS

Cross-reactivity studies were carried out by enzyme-linked immunoadsorbent assay (ELISA) and immunoblot inhibition using both rabbit antiserum raised against EN and pooled sera from patients' EN-positive skin test.

RESULTS

A large number (82%) of EN-sensitive patients showed positive skin reactivity to other fungal extracts. ELISA inhibition revealed >50% inhibition in binding of EN-specific rabbit antibodies with Alternaria alternata, Curvularia lunata, Cladosporium herbarum, and Penicillium citrinum extract, whereas the other extracts showed only 20 to 40% inhibition. Rabbit antisera to A. alternata, C. herbarum, and C. lunata reacted with five to seven bands in EN, demonstrating the presence of shared antigens among these fungi. EN requires an amount of 100 ng for 50% IgE ELISA inhibition, whereas 175 ng of A. alternata, 160 ng of C. lunata, and 268 ng of C. herbarum and P. citrinum were required for the same. IgE immunoblot and immunoblot inhibition further revealed that 43-, 26-, and 17-kD allergenic bands were shared by EN and A. alternata, whereas the 80- and 37-kD bands were common to both EN and C. lunata. EN and C. herbarum shared 63- and 36-kD allergenic bands, whereas EN and P. citrinum shared the 34-kD band.

CONCLUSION

EN showed maximum cross-reactivity with A. alternata followed by C. lunata, C. herbarum, and P. citrinum. This information will be useful in treating EN-allergic patients.

Panfungal PCR and multiplex liquid hybridization for detection of fungi in tissue specimens

A procedure based on panfungal PCR and multiplex liquid hybridization was developed for the detection of fungi in tissue specimens. The PCR amplified the fungal internal transcribed spacer (ITS) region (ITS1-5.8S rRNA-ITS2). After capture with specific probes, eight common fungal pathogens (Aspergillus flavus, Aspergillus fumigatus, Candida albicans, Candida krusei, Candida glabrata, Candida parapsilosis, Candida tropicalis, and Cryptococcus neoformans) were identified according to the size of the amplification product on an automated sequencer. The nonhybridized products were identified by sequencing. The performance of the procedure was examined with 12 deep-tissue specimens and 8 polypous tissue biopsies from the paranasal sinuses. A detection level of 0.1 to 1 pg of purified DNA (2 to 20 CFU) was achieved. Of the 20 specimens, PCR was positive for 19 (95%), of which 10 (53%) were hybridization positive. In comparison, 12 (60%) of the specimens were positive by direct microscopy, but only 7 (35%) of the specimens showed fungal growth. Sequencing of the nonhybridized amplification products identified an infecting agent in six specimens, and three specimens yielded only sequences of unknown fungal origin. The procedure provides a rapid (within 2 days) detection of common fungal pathogens in tissue specimens, and it is highly versatile for the identification of other fungal pathogens.

Allergic fungal sinusitis: a four-year follow-up

Allergic fungal sinusitis (AFS), first described over 18 years ago and subsequently identified using established criteria, remains a challenge to treat. Our protocol has included complete functional endoscopic sinus surgery to remove the fungal load and restore physiologic mucous clearance. The patient is treated with prednisone for several months and followed monthly with total serum IgE levels and an established endoscopic mucosal staging system. A group of 11 patients first treated in 1994 and presented at the 1995 American Rhinology Society Spring meeting are being presented again to provide an update on their progress over the past four years. A great deal of experience has been gained from their treatment and has continued to modify our postoperative medical management. An overview of AFS, our evolving and current treatment protocol, and possible future trends are discussed in this paper.

Geographic variation in allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) has a worldwide distribution. This survey of 20 otolaryngologic practices throughout the United States confirmed a variation in the frequency of AFRS relative to endoscopic sinus procedures performed for all other diagnoses. The highest incidence occurred in Memphis, Tennessee at 23%, with three other southern practices reporting a frequency of at least 10%. In the northern locations the frequency ranged from 0 to 4%. No correlation with mould counts was demonstrated, possibly because of incomplete mould data relative to most of the surgical locations.

Allergic fungal rhinosinusitis: perioperative management, prevention of recurrence, and role of steroids and antifungal agents

Allergic fungal sinusitis can best be thought of as chronic fungal affectation (not an infection) of the sinuses to which the body's immune system hyperreacts, thereby creating significant inflammation, edema, obstruction, and polyposis. Currently it is felt that allergic fungal sinusitis requires both surgical and medical management. The effectiveness and required duration of the various medical treatments remain unknown and are under active investigation. Both surgical intervention and the use of systemic steroids are recommended in the treatment of allergic fungal sinusitis. Experience with surgical and medical management, follow-up of patients, and proposed treatment protocols are discussed.