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At least 19 recordsLinked to original sources
PubMed1990

Mitochondrial DNA analysis of Exophiala jeanselmei and Exophiala dermatitidis.

Mitochondrial DNA (mtDNA) analysis with Hae III, Hind III and Msp I was performed in 45 Exophiala jeanselmei strains (30 Phialophora jeanselmei and 154 Phialophora gougerotii strains) and 31 Exophiala dermatitidis strains. The results were as follows, 1) P. jeanselmei and P. gougerotii are identical, 2) E. jeanselmei is classified into 18 types based on restriction profiles, 3) two strains of E. jeanselmei CBS 577.76 and CBS 578.76 are identified as E. dermatitidis, 4) E. dermatitidis has no intraspecific variation and is definitely distinct from E. jeanselmei, 5) E. jeanselmei is suggested to be a complex organism because of extensive mtDNA polymorphism.

DNA, Fungal↗
PubMed2006

Catheter-associated fungemia due to Exophiala oligosperma in a leukemic child and review of fungemia cases caused by Exophiala species.

A case of catheter-associated fungemia due to Exophiala oligosperma in a 3-year-old leukemic child is presented. The etiologic agent was isolated from blood specimens and the catheter tip. The isolate was identified by its morphological characteristics and DNA sequencing of the internal transcribed spacer region of rDNA. Despite initial amphotericin B and itraconazole therapy, the child's fever subsided only after removal of the catheter. A review of the medical literature revealed 29 cases of infection due to Exophiala species. Twenty-three of these 29 patients had a CVC in place when they developed fever or other manifestations of fungemia. Withdrawal of the CVC together with amphotericin B and/or itraconazole therapy generally resulted in a good prognosis.

Catheterization, Central Venous↗
PubMed1989

Deoxyribonucleic acid hybridization studies of Exophiala dermatitidis and Exophiala jeanselmei.

Exophiala dermatitidis and Exophiala jeanselmei share similar morphological features and have been confused with each other. To clarify the relationship between the two fungi, we conducted a deoxyribonucleic acid (DNA)-DNA hybridization study using a dot blot method. Between E. dermatitidis and E. jeanselmei, only a very low level of DNA relatedness was seen and it was confirmed that these two fungi are distinct species based on DNA similarity. Close correspondence of DNA from the isolates of E. dermatitidis was obtained, whereas the isolates of E. jeanselmei were divided into 6 groups according to their DNA similarity and a possibility was shown that E. jeanselmei is composed of genetically heterogeneous groups. The subdivision of the species E. jeanselmei by the DNA-DNA hybridization method was in agreement with serotyping exoantigens. This result suggests that DNA-DNA hybridization studies provide an excellent tool for the identification and grouping of pathogenic dematiaceous fungi.

DNA, Fungal↗
PubMedDate not supplied

A human isolate of Exophiala (Wangiella) dermatitidis forming a catenate synanamorph that links the genera Exophiala and Cladophialophora.

A strain of the black yeast Exophiala dermatitidis displayed a hydrophobic synanamorph consisting of acropetal chains of lemon-shaped conidia, morphologically similar to those of Cladophialophora bantiana. The occurrence of the two conidial types in a single strain suggests a taxonomic affinity between Exophiala and Cladophialophora and provides support to the supposition that Cladophialophora, a possible anamorph genus of Herpotrichiellaceae, is related to black yeasts rather than to Cladosporium, which has teleomorphs in the Mycosphaerellaceae.

Exophiala↗
PubMed1999

Mitochondrial DNA analysis of Exophiala jeanselmei var. lecanii-corni and Exophiala castellanii.

A Japanese clinical isolate (KU-A-0094) which was identified by de Hoog et al. as Exophiala jeanselmei var. lecanii-corni with difficulty, was compared with 5 strains including the type cultures of E. jeanselmei var. lecanii-corni, var. jeanselmei and E. castellanii using RFLP (restriction fragment length polymorphism) patterns of mtDNA (mitochondrial DNA). RFLP patterns of KUA-0094 were identical with those of E. jeanselmei var. lecanii-corni and different from those of E. castellanii with restriction enzymes of HaeIII, MspI and hindIII. Therefore, de Hoog et al.'s identification of KU-A-0094 was confirmed. Additionally, mtDNA-RFLP patterns of E. jeanselmei var. lecanii-corni and E. jeanselmei var. jeanselmei were also different from each other. Consequently E. jeanselmei var. lecanii-corni seem to be a species in its own right rather than a variant of E. jeanselmei.

DNA, Fungal↗
PubMed2003

Species diversity and polymorphism in the Exophiala spinifera clade containing opportunistic black yeast-like fungi.

A monophyletic group of black yeast-like fungi containing opportunistic pathogens around Exophiala spinifera is analyzed using sequences of the small-subunit (SSU) and internal transcribed spacer (ITS) domains of ribosomal DNA. The group contains yeast-like and annellidic species (anamorph genus Exophiala) in addition to sympodial taxa (anamorph genera Ramichloridium and Rhinocladiella). The new species Exophiala oligosperma, Ramichloridium basitonum, and Rhinocladiella similis are introduced and compared with their morphologically similar counterparts at larger phylogenetic distances outside the E. spinifera clade. Exophiala jeanselmei is redefined. New combinations are proposed in EXOPHIALA: Exophiala exophialae for Phaeococcomyces exophialae and Exophiala heteromorpha for E. jeanselmei var. heteromorpha.

Ascomycota↗
PubMed1995

Nutritional physiology of type isolates of currently accepted species of Exophiala and Phaeococcomyces.

Nutritional physiological and tolerance tests were performed for all type strains of species currently classified in the black yeast genera Exophiala and Phaeococcomyces, including some additional type strains of taxa recently reidentified as Exophiala species. Most described Exophiala species can be distinguished by physiological characters. Exophiala jeanselmei with its varieties, and E. castellanii should all be retained as separate taxa. The pairs of strains Mycotorula schawii/Exophiala dermatitidis, Hormodendrum negronii/Exophiala jeanselmei var. lecaniicorni and Sporotrichum gougerotii/Torulabergeri were found to be conspecific. Phenetic analyses of physiological data support the identity of Phaeococcomyces exophialae as a yeast-like synanamorph of Exophiala spinifera. The taxonomic positions of the genera Nadsoniella, Phaeoannellomyces and Wangiella are discussed. The genera Exophiala and Phaeococcomyces are unrelated.

Exophiala↗
PubMed1999

In vitro activities of five antifungal agents against pathogenic Exophiala species.

OBJECTIVES: To examine the in vitro activities of five antifungal agents against common pathogenic Exophiala species; to detect the minimum inhibitory concentration (MIC) discrepancies among different drugs and different species; to evaluate the role of the influence factors in MIC determination; and to establish a standard method for the antifungal susceptibility testing of Exophiala spp. METHODS: MICs of itraconazole (ICZ), fluconazole, ketoconazole, amphotericin B (AmB) and 5-flucytosine against 5 species (57 strains) of Exophiala spp were determined by modified NCCLS M27-A broth microdilution method. Two inoculum sizes (0.5 x 10(3)-2.5 x 10(3) CFU/ml and 0.5 x 10(4)-2.5 x 10(4) CFU/ml) and three incubation times (4, 7 and 10 days) were evaluated. The minimum fungicidal concentrations (MFC) of itraconazole against 20 Exophiala strains were also detected. RESULTS: All the tested Exophiala species were sensitive to AmB and ICZ. MICs varied among different species and drugs. Resistant strains to different drugs existed in this genus. The proper inoculum density was about 0.5 x 10(3) CFU/ml to 2.5 x 10(3) CFU/ml, and the 4-day incubation time was suitable for more than 90% of the strains. CONCLUSIONS: AmB or ICZ may serve as the first choice in treatment of phaeohyphomycosis. A standard microdilution procedure for MIC detection of Exophiala species is established in this experiment. The inoculum size and incubation time are the essential factors in the standardization of antifungal susceptibility testing of filamentous fungi. We hope this experiment may correlate well with the clinical treatment of phaeohyphomycosis caused by Exophiala species.

Amphotericin B↗
PubMed2002

Phaeohyphomycosis caused by Exophiala species in immunocompromised hosts.

Exophiala species are rarely implicated in clinical diseases. In the past 2 years, we have treated phaeohyphomycosis caused by Exophiala species in three immunocompromised patients. Two of these patients presented with subcutaneous abscess or cutaneous verrucous lesions due to Exophiala jeanselmei. The former, an 81-year-old woman, had pulmonary tuberculosis and the latter, a 62-year-old man, had undergone heart transplantation and was receiving immunosuppressive treatment. The third patient, a 62-year-old woman, had acute lymphoblastic leukemia and developed lymphadenitis due to Wangiella (Exophiala) dermatitidis. In each case, the fungus was discovered on a Gram stain of the aspirated material and was identified by conventional tests. One patient died of bacterial pneumonia with acute respiratory distress syndrome and the other two were treated successfully with surgical excision and antifungal agents. With the more frequent and widespread use of immunosuppressive agents, the incidence of Exophiala infection will certainly increase. Surgical excision or debridement with or without antifungal agents may offer the possibility of cure for phaeohyphomycosis due to Exophiala species.

Aged↗
PubMed1991

Exoantigen test for the rapid identification of Exophiala spinifera.

Exophiala spinifera, one of the etiologic agents of subcutaneous phaeohyphomycosis, may be wrongly identified as Exophiala jeanselmei because of the morphologic similarity of the two species. A reagent containing a precipitin specific for E. spinifera was produced by absorbing antiserum to E. spinifera with E. jeanselmei serotype 1 antigen. Using this absorbed antiserum, we were able to correctly identify isolates of E. spinifera and differentiate them from those of Exophiala alcalophila, E. jeanselmei (serotypes 1, 2 and 3), Exophiala moniliae, Exophiala pisciphila, Exophiala salmonis, Phaeoannellomyces werneckii and Wangiella dermatitidis.

Antigens, Fungal↗
PubMed2000

In vitro susceptibilities of 11 clinical isolates of Exophiala species to six antifungal drugs.

The antifungal activities of miconazole, terbinafine, itraconazole, UR 9825, voriconazole and amphotericin B against 11 clinical isolates of Exophiala spp. were tested by the broth microdilution method. All drugs were very active against Exophiala spp.. The 90% minimal inhibitory concentration (MIC90) ranged from 0.125 to 1 microgram ml-1. Terbinafine was the most active drug against Exophiala spinifera, Exophiala dermatitidis and Exophiala castellanii and seems to be a promising agent in the treatment of infections caused by these fungi.

Antifungal Agents↗
PubMed2006

Exophiala crusticola anam. nov. (affinity Herpotrichiellaceae), a novel black yeast from biological soil crusts in the Western United States.

A novel black yeast-like fungus, Exophiala crusticola, is described based on two closely related isolates from biological soil crust (BSC) samples collected on the Colorado Plateau (Utah) and in the Great Basin desert (Oregon), USA. Their morphology places them in the anamorphic genus Exophiala, having affinities to the family Herpotrichiellaceae (Ascomycota). Phylogenetic analysis of their D1/D2 large subunit nuclear ribosomal RNA (LSU nrRNA) gene sequences suggests that they represent a distinct species. The closest known putative relative to Exophiala crusticola is Capronia coronata Samuels, isolated from decorticated wood in Westland County, New Zealand. The holotype for Exophiala crusticola anam. nov. is UAMH 10686 and the type strain is CP141bT (=ATCC MYA-3639T=CBS 119970T=DSM 16793T). Dark-pigmented fungi appear to constitute an important heterotrophic component of soil crusts and Exophiala crusticola represents the first description of a dematiaceous fungus isolated from BSCs.

DNA, Fungal↗
PubMed2005

[Exophiala species--a rare cause of endocarditis with cerebral abscess formation].

Exophiala species belong to the dematiaceous fungi. Occurring worldwide, they are a rare cause of human infection. We present the case of a 75-year-old immunocompetent patient with a cardiogenic embolic anterior cerebral artery infarction. Echocardiography revealed endocarditis of the aortic valve. Antibiotic therapy was initiated after susceptibility testing (blood cultures were positive for Staphylococcus aureus, and liquor was normal), with a subsequent fall in serologic markers of infection and resolution of the signs of endocarditis on echocardiography. However, 6 weeks after initiation of antibiotic therapy, abscesses were seen in the infarct region on CT scan, although antimicrobial treatment was still continued. At this stage, the CSF showed an inflammatory process, and Exophiala species, susceptible to voriconazol, could be detected in liquor cultures. However, antifungal therapy with voriconazol could not prevent severe sepsis and death from multiorgan failure. Autopsy revealed the clinically supposed Exophiala endocarditis with metastatic cerebral abscesses. In accordance with other published case reports, a fatal outcome in disseminated Exophiala infection might only be prevented by aggressive therapy consisting of early surgical removal of the foci and combined antifungal agents.

Aged↗
PubMed2003

Early diagnosis of Exophiala CAPD peritonitis by 18S ribosomal RNA gene sequencing and its clinical significance.

Phenotypic identification of fungi in clinical microbiology laboratories is often difficult and late, especially for slow growing and rarely encountered fungi. We describe the application of 18S ribosomal RNA (rRNA) gene sequencing in the early diagnosis of a case of Exophiala peritonitis. A yeast-like fungus was isolated from the dialysate fluid of a 66-year-old man undergoing continuous ambulatory peritoneal dialysis. It grew slowly after 12 days of incubation to yield mature cultures to permit recognition of microscopic features resembling those of Exophiala, a dematiacerous mold. 18S rRNA gene sequencing provided results 12 days earlier than phenotypic identification and revealed 15 base difference (0.9%) between the isolate and Exophiala sp. strain GHP 1205 (GenBank Accession no. AJ232954), indicating that the isolate most closely resembles a strain of Exophiala species. The patient responded to 4 weeks of intravenous amphotericin B therapy. Early identification of the fungus was important for the choice of anti-fungal regimen. As opportunistic fungal infections in immunocompromised patients are globally emerging problems, the development of molecular techniques for fungal identification is crucial for early diagnosis and appropriate treatment.

Aged↗
PubMed2003

Successful treatment of invasive stomatitis due to Exophiala dermatitidis in a patient with acute myeloid leukemia.

BACKGROUND: Although the most common orofacial fungal infection in immunocompromised patients is candidosis, infections caused by virulent molds, such as Aspergillus spp. and Furarium spp. are being recognized with increasing frequency. We report a case of oral Exophiala infection in a 39-year-old woman with acute myeloid leukemia. METHODS: Clinical records of the patient were reviewed and the following additional information was collected: histological and microbiological evidence; identification of the causative organism; in vitro antifungal susceptibility. RESULTS: The patient developed a necrotic ulcer surrounded by a violaceous rim in the gingiva during neutropenia. Exophiala dermatitidis was identified as the causative organism by histopathological examination and culture, and finally confirmed by sequencing of the ribosomal DNA internal transcribed space domain. In vitro, amphotericin B was found to show strong activity against the Exophiala isolate while itraconazole showed less activity. The patient was successfully treated with parenteral amphotericin B and oral itraconazole in combination with surgical removal of the fungi focus. CONCLUSION: Local excision with adequate antifungal agents can be used to treat immunocompromised patients with Exophiala stomatitis, based on early diagnosis.

Administration, Oral↗
PubMed2002

High prevalence of the neurotrope Exophiala dermatitidis and related oligotrophic black yeasts in sauna facilities.

The black yeast Exophiala dermatitidis, an agent of fatal brain infections in East Asia, is common in European steam baths. The related fungi Sarcinomyces phaeomuriformis and Exophiala mesophila were isolated from locations in these complexes with lower ambient temperature and/or moisture. The latter two species had dry, rather than slimy, colonies and lower maximum growth temperatures (38 degrees C, 32 degrees C) than E. dermatitidis (42 degrees C). Exophiala dermatitidis produces abundant extracellular polysaccharide (EPS). The only E. dermatitidis strains lacking EPS were found outside the steam baths. Therefore it is likely that the extracellular polysaccharides commonly produced by E. dermatitidis are significant to survival under hot and moist conditions. Substrates sampled as controls, such as fruit surfaces and human faeces, yielded Exophiala dermatitidis at very low frequency.

Baths↗
PubMed1989

Subcutaneous phaeohyphomycosis of the finger caused by Exophiala spinifera.

A patient with severe rheumatoid arthritis treated with prednisone had a painless soft tissue nodule develop on the dorsal aspect of the ring finger. She denied any history of hand trauma, animal exposure, or systemic symptoms such as fever or malaise. Fungal cultures performed on an aseptically obtained aspirate of this lesion demonstrated dark, olive-black creamy colonies on Sabouraud's agar. Slide cultures made from mold colonies produced slender conidial forms with annellations and spine-like conidiophores, features characteristic of Exophiala spinifera. The lesion was surgically excised, and the patient was successfully treated with a course of oral itraconazole. This nodular lesion has not recurred at the time of this writing. Exophiala species are difficult to differentiate, and E. spinifera may be confused with Exophiala jeanselmei. A literature review will consider Exophiala species and clinical manifestations produced by these dematiaceous fungi.

Arthritis, Rheumatoid↗