Isolation of Exophiala jeanselmei associated with esophageal pathology--three cases, laboratory and clinical features

Cutaneous Phaeohyphomycosis of the Right Hand Caused by Exophiala jeanselmei: A Case Report and Literature Review

Exophiala spp. is increasingly reported as a pathogen causing the cutaneous, subcutaneous or invasive infection. In this report, we present a case of cutaneous phaeohyphomycosis due to E. jeanselmei on the right hand of a farmer, who suffered from this disease three years ago which had not been definitely diagnosed until he was admitted to our hospital. In our hospital, a potential fungal pathogen was observed by histopathological examination, and then was recovered and identified as E. jeanselmei by sequencing its internal transcribed spacer region. After 4 weeks of antifungal treatment, his hand recovered very well. To investigate the in vitro susceptibility of E. jeanselmei isolates to antifungal agents and compare the characteristics of their related infections among immunocompetent and immunocompromised patients, we reviewed 84 cases published in PubMed database between 1980 and 2020.

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.

Nosocomial fungemia due to Exophiala jeanselmei var. jeanselmei and a Rhinocladiella species: newly described causes of bloodstream infection

Fungi have become increasingly important causes of nosocomial bloodstream infections. The major cause of nosocomial fungemia has been Candida spp, but increasingly molds and other yeasts have caused disease. Exophiala jeanselmei and members of the genus Rhinocladiella are dematiaceous moulds, which have been infrequently associated with systemic infection and have not been described as causes of fungemia. In this paper, the occurrence of 23 cases of fungemia due to these organisms over a 10-month period is reported and the clinical characteristics of patients and outcomes are described. The majority of patients were immunosuppressed; 21 of 23 (91%) had received blood products and 78% had a central venous catheter. All patients had at least one manifestation of fever, but only one patient had signs or symptoms suggesting deep-seated infection. Antifungal therapy was given to 19 of the 23 patients; of those who did not receive therapy, 3 died prior to the culture result and 1 had been discharged without therapy. Antifungal susceptibility of the organisms showed activity of amphotericin B, itraconazole, and the new triazole antifungals voriconazole and posaconazole. E. jeanselmei and Rhinocladiella species are potential causes of nosocomial fungemia and may be associated with systemic infection.

Exophiala Jeanselmei Infection in a Patient with Two Primary Malignancies

Background:

Dematiaceous fungi are emerging as an important pathogen, particularly in individuals on immunosuppressive medications. These fungi produce brown to black pigment and are responsible for a wide spectrum of diseases, including superficial infections of the skin and eye and, uncommonly, deep infections involving the central nervous system and internal organs.

Objective:

We present a male patient with localized, cutaneous Exophiala jeanselmei infection.

Methods:

We review the literature and present a brief discussion of phaeohyphomycotic infections, their clinical features, and their treatment modalities.

Results:

Workup of our patient revealed an underlying hepatic lymphoma and pulmonary squamous cell carcinoma.

Conclusions:

Phaeohyphomycotic infections, although uncommon, are increasingly recognized as important pathogens in patients who are immunologically compromised as a result of long-term steroid or other immunosuppressive therapy. Infections by these organisms in healthy-appearing individuals should prompt one to consider an immunodeficiency state and appropriate workup should be performed.

Mycetoma due to Exophiala jeanselmei and Mycobacterium chelonae in a 73-year-old man with idiopathic CD4+ T lymphocytopenia

Exophiala jeanselmei and Mycobacterium chelonae were isolated from cutaneous nodules in a 73-year-old man with mycetoma of the right lower leg. Further evaluation revealed CD4+ lymphocytopenia without evidence of HIV infection. Antibodies to HIV 1/2, p24 antigen and HIV 1/2 (PCR) and reverse transcriptase activity were not detectable. The patient was not a member of any HIV risk group. He had not previously undergone therapy or suffered from immunodeficiency. This case clearly demonstrates that infections with opportunistic moulds and/or atypical mycobacteria should be taken into consideration not only in patients with classical immundeficiency diseases but also in apparently healthy patients because infection with these agents can be the first sign of underlying immunodeficiency.

Feo-hifomicose subcutânea por Exophiala jeanselmei: registro de três casos em transplantados renais

São registrados três casos de feo-hifornicose subcutânea em transplantados renais provocados pela Exophiala jeanselmei (Langeron) McGinnis et Padhye 1977, fungo demácio capaz, também, de produzir raramente eumicetoma de grãos pretos. Este fungo, segundo KWON-CHUNG & BENNETT, 1992(27) é antigenicamente muito heterogêneo, sendo identificados até o presente momento três sorotipos com subgrupos dentro de cada um deles. A feo-hifomicose subcutânea vem se tornando cada vez mais freqüente em transplantados renais, submetidos a terapêutica imunodepressora. Como a Exophiala jeanselmei já foi isolada do meio ambiente, torna-se dificil explicar a patogenia desses casos por um despertar ou reativação de processos quiescentes. Os Autores fizeram ampla revisão da literatura, registrando principalmente os casos de feo-hifomicose publicados no Brasil. Sugerem também, eventual ação fungistática da ciclosporina A sobre a Exophiala jeanselmei.

The medically important dematiaceous fungi and their identification

Dematiaceous fungi include a large group of organisms that are darkly pigmented (dark brown, olivaceous, or black). In most cases the pigment is melanin, and specifically, dihydroxynaphthalene melanin. The diseases produced include chromoblastomycosis, eumycotic mycetoma, and phaeohyphomycosis. Phaeohyphomycosis is a new classification for a diverse group of previously known entities grouped together on the basis of finding dematiaceous hyphal and/or yeast-like forms in tissue; tissue involvement may be superficial, cutaneous and corneal, subcutaneous, or systemic. Identification of these fungi is based mostly upon morphology. Important structures include annellides (Phaeoannellomyces, Exophiala), phialides (Phialophora, Wangiella), adelophialides (Phialemonium without collarettes, Lecythophora with collarettes), differentiation of conidiophores (Xylohypha versus Cladosporium) and conidial hilum, septation and germination (Bipolaris, Drechslera, Exserohilum). Useful laboratory tests include the 12% gelatin test (controversial), nitrate assimilation (W. dermatitidis is negative, most other species are positive), and determination of temperature maxima (especially 37 degrees C for E. jeanselmei, 40 degrees C for W. dermatitidis and B. spicifera, 42 degrees C for X. bantiana, and 45 degrees C for Dactylaria constricta var. gallopava and Scedosporium inflatum).

Hyalohyphomycosis and phaeohyphomycosis: two global disease entities of public health importance

Two relatively new opportunistic diseases--hyalohyphomycosis and phaeohyphomycosis--are the byproduct, in most cases, of the progress being made in combating microbial and non-microbial diseases. Immunologically impaired hosts have become vulnerable to infection by fungi that were long considered to be innocuous. The currently known etiologic agents of these two diseases are listed and pertinent literature references are cited. The basic histologic differences between phaeohyphomycosis and chromoblastomycosis was emphasized and illustrated.

Pathogenicity of a fungus resembling Wangiella dermatitidis isolated from edible mushrooms

A fungus resembling the human pathogen Wangiella dermatitidis (Kano) McGinnis, a dematiaceous hyphomycete, was recovered from imported desiccated "black fungus" mushrooms (Auricularia polytrichia (Mont.) Sacc.), a food item popular in Far Eastern cuisine. Except for its conidia, which are mostly reniform to allantoid rather than ovoid as is characteristic for W. dermatitidis, and the undecided mode of conidiogenesis, the isolate closely resembles W. dermatitidis in gross and microscopic morphology, thermotolerance, and general and neurotrophic infectivity patterns in mice injected intraperitoneally. The foodborne isolate was also infective for infant mice inoculated by oral intubation. The systematic position of the isolate is still under investigation. There has been no previous report of W. dermatitidis or of a fungus resembling it occurring in or on foods or of the infectivity of a fungus for a mammalian host by oral intubation.