Etymologia: Emmonsia

نویسنده

  • Ronnie Henry
چکیده

mold isolated from pleural fluid and blood of the patient produced velvety, white colonies on Sabouraud dextrose agar (Figure, panel B). D1D2 rDNA sequenc-ing identified the mold as E. parva. Because we found no previous reports of E. parva disseminated infections, we sent the isolate to a reference laboratory (University of Alberta Microfungus Collection and Herbarium, Edmon-ton, Alberta, Canada). Using culture characteristics and internal transcribed spacer and D1D2 sequences, the laboratory identified the fungus as a novel Emmonsia species not yet formally described (Figure 1 in Schwartz et al. grown on different culture media incubated at 30°C, the fungus lacked co-nidia but formed helically coiled, yellow-brown hyphae (Figure, panel C). When incubated on potato dextrose agar at 35°C, the fungus converted into a yeast-like form: clusters of small, irregularly shaped cells extending into short filaments. Antifungal susceptibility testing of the mold phase was performed at the A literature review of human Emmonsia infections is challenging because these organisms have undergone multiple taxonomic revisions (2). Most reports of adiaspi-romycosis base the diagnosis solely on the appearance of adiaspores in histopathologic specimens (5,6), and some published Emmonsia cases might have misidentified the causative organism (1). Disseminated Emmonsia infection appears to be a separate clinical entity from adiaspiromycosis (1). Human adiaspiromycosis is primarily a self-limited pulmonary infection caused by E. crescens, which is not associated with immunosuppression or fungemia. Disseminated Emmonsia The isolation of Haplosporangium parvum n. sp. and Coccidioides immitis from wild rodents: their relationship to coccidioidomycosis. et al. 50 years of Emmonsia disease in humans: the dramatic emergence of a cluster of novel fungal pathogens. E mmonsia is a genus of soil fungus that can cause adiaspiromycosis, a pulmonary disease common in wild animals, but rare in humans, as well as disseminated disease. When aerosolized spores are inhaled, they enlarge dramatically, from 2–4 μm to 40–500 μm in diameter. Because these swollen cells do not replicate, Emmons and Jellison termed them " adiaspores " (from the Greek a [ " not " ] + dia [ " by " ] + spora [ " sowing " ]. Emmonsia was first described by Chester W. Emmons, senior mycologist with the US Public Health Service, as Haplosporangium parvum in 1942. In 1958, it was reclassified into a separate genus and named in honor of Emmons. Recent phylogenetic analyses have concluded that fungi in this genus are polyphyletic, and proposed taxonomic changes may render …

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Genomics and Comparative Genomic Analyses Provide Insight into the Taxonomy and Pathogenic Potential of Novel Emmonsia Pathogens

Over the last 50 years, newly described species of Emmonsia-like fungi have been implicated globally as sources of systemic human mycosis (emmonsiosis). Their ability to convert into yeast-like cells capable of replication and extra-pulmonary dissemination during the course of infection differentiates them from classical Emmonsia species. Immunocompromised patients are at highest risk of emmons...

متن کامل

Ajellomyces crescens sp. nov., taxonomy of Emmonsia spp., and relatedness with Blastomyces dermatitidis (teleomorph Ajellomyces dermatitidis).

Adiaspiromycosis is known primarily as a pulmonary infection of small burrowing mammals and rarely of humans, in which the tissue spore form consists of a large, globose, thick-walled, non-proliferating structure called an adiaspore. The causative agents have been placed in Emmonsia or Chrysosporium and treated as either two species or varieties. Emmonsia parva (= Chrysosporium parvum var. parv...

متن کامل

Emmonsia crescens infection in a British water vole (Arvicola terrestris).

Emmonsia crescens, a dimorphic fungus of the order Onygenales, is primarily a pathogen of lower animals and rarely humans. Inhaled conidia of E. crescens fail to germinate in the lungs, and instead simply enlarge in lung tissue to become giant adiaspores. We present here the case of fatal Emmonsia crescens infection in a wild-caught British water vole (Arvicola terrestris). Histopathological ex...

متن کامل

Molecular genetic variation in Emmonsia crescens and Emmonsia parva, etiologic agents of adiaspiromycosis, and their phylogenetic relationship to Blastomyces dermatitidis (Ajellomyces dermatitidis) and other systemic fungal pathogens.

Emmonsia crescens, an agent of adiaspiromycosis, Blastomyces dermatitidis, the agent of blastomycosis, and Histoplasma capsulatum, the agent of histoplasmosis, are known to form meiotic (sexual) stages in the ascomycete genus Ajellomyces (Onygenaceae, Onygenales), but no sexual stage is known for E. parva, the type species of the genus Emmonsia. To evaluate relationships among members of the pu...

متن کامل

A dimorphic fungus causing disseminated infection in South Africa.

BACKGROUND The genus emmonsia contains three species that are associated with human disease. Emmonsia crescens and Emmonsia parva are the agents that cause adiaspiromycosis, and one human case of Emmonsia pasteuriana infection has been described. We report a fungal pathogen within the genus emmonsia that is most closely related to E. pasteuriana in human immunodeficiency virus (HIV)-infected ad...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره 23  شماره 

صفحات  -

تاریخ انتشار 2017