Onychomycosis Caused byChaetomium globosum

Abstract

Onychomycosis is usually caused by dermatophytes, but some nondermatophytic molds and yeasts are also associated with invasion of nails. The genus Chaetomium is a dematiaceous nondermatophytic mold found in soil and plant debris as a saprophytic fungus. We report the first Korean case of onychomycosis caused by Chaetomium globosum in a 35-year-old male. The patient showed brownish-yellow discoloration and subungual hyperkeratosis on the right toenails (1st and 5th) and left toenails (1st and 4th). Direct microscopic examination of scraping on the potassium hydroxide preparation revealed septate hyphae and repeated cultures on Sabouraud's dextrose agar (SDA) without cycloheximide slants showed the same fast-growing colonies, which were initially velvety white then turned to dark gray to brown. However, there was no growth of colony on SDA with cycloheximide slants. Brown-colored septated hyphae, perithecia and ascospores were shown in the slide culture. The DNA sequence of internal transcribed spacer region of the clinical sample was a 100% match to that of C. globosum strain ATCC 6205 (GenBank accession number EF524036.1). We confirmed C. globosum by KOH mount, colony, and light microscopic morphology and DNA sequence analysis. The patient was treated with 250 mg oral terbinafine daily and topical amorolfine 5% nail lacquer for 3 months.

Diversity and taxonomy ofChaetomiumand chaetomium-like fungi from indoor environments

“…This species is also the most common human pathogen mainly associated with onychomycosis (Naidu et al., 1991, Stiller et al., 1992, Aspiroz et al., 2007, Latha et al., 2010, Tullio et al., 2010, Hwang et al., 2012, Lagacé and Cellier, 2012, Kim et al., 2013). In addition, some other indoor chaetomium-like species were also reported in clinical cases, such as D. funicola (= C. funicola , Koch & Haneke 1965), O. brasiliensis (= C. brasiliense , Hubka et al.…”

Emergence Shapes the Structure of the Seed Microbiota

“…In the same vein, several fungal aOTUs significantly enriched in seedlings compared to seeds correspond to ubiquitous cosmopolitan taxa (e.g., Penicillium, Chaetomium globosum, Rhizopus oryzae) often found in soil and on seed surfaces. These bacterial and fungal taxa have in common a fastgrowing ability (51,52,53,54,55,56) that may explain their rapid colonization of seedlings.…”

“…In addition, fungal aOTUs enriched during emergence, such as Trichoderma viride (68) and Chaetomium globosum (69), corresponded to biocontrol fungal species, which have the ability to colonize plant tissues both as epiphytes and as endophytes. All these microbial taxa enriched in seedlings are capable of rapid growth in response to increase in nutrient availability (52,54,55,56), which may indicate that r-strategists (70) are selected during emergence. Enhanced colonization of seedlings by copiotrophic taxa suggests that competitive exclusion probably occurs between functional equivalent species.…”

The first Turkish case of onychomycosis caused by Chaetomium globosum in an immunocompetent patient

“…These species produce chaetoglobosins A and C and mycotoxin exposure may be associated with cutaneous, subcutaneous, and opportunistic fungal infection (7). Until today, author reported a small number of onycomycosis caused by C. globosum in adult patients (12)(13)(14)(15)(16). Among these cases only one mixed toenail infection caused by C. Globosum and Trichophyton mentagrophytes was reported (17).…”

“…In all cases, male patients were found to be more affected than female patients. In In literature, successful treatment was reported by using itraconazole and terbinafine (13,16).…”