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Brazilian Journal of Microbiology :... Mar 2023Keratinophilic fungi are mostly soil-inhabiting organisms with occasional infections in humans and animals. Even though most dermatophytes are host-adapted,... (Review)
Review
Keratinophilic fungi are mostly soil-inhabiting organisms with occasional infections in humans and animals. Even though most dermatophytes are host-adapted, cross-species infections are common by zoophilic and geophilic dermatophytes. N. nana is considered an etiological agent of ringworm in pigs but has also been isolated from other animals, including humans. However, it also possesses many characteristics of geophilic dermatophytes including the ability to grow in soil. N. nana produces characteristic pear-shaped macroconidia and usually exhibits an ectothrix pattern of hair infection. It has been isolated from dermatitis lesions as well as from soil. N. nana infections in pigs are not of much concern as far as economy or health is concerned. But it has been associated with onychomycosis and gonathritis in humans, which are significant in human medicine. The shift in the predominance of dermatophytes in humans and the ability to evolve into a potential tinea pathogen necessitates more understanding of the physiology and genetics of N. nana. In this review, we have attempted a detailed analysis of the studies about N. nana, emphasizing growth and cultural characters, physiology, isolation, infection in humans and animals, molecular characterization and antifungal susceptibility.
Topics: Humans; Animals; Swine; Arthrodermataceae; Dermatomycoses; Onychomycosis; Antifungal Agents; Cross Infection
PubMed: 36437438
DOI: 10.1007/s42770-022-00880-5 -
Microbial Ecology Aug 2022The European hedgehog (Erinaceus europaeus Linnaeus) frequently colonises areas located close to human life in cities, as these are more suitable nest sites offering an...
The European hedgehog (Erinaceus europaeus Linnaeus) frequently colonises areas located close to human life in cities, as these are more suitable nest sites offering an abundance of food and allowing avoidance of predators. However, urbanisation has a significant impact on the epidemiology of infectious diseases, including dermatophytoses, the primary source of which are wild animals. In this study, we determined the spectrum of dermatophytes isolated from the European hedgehog and assessed their susceptibility profile to antifungal drugs. Symptomatic and asymptomatic dermatophyte infections were observed in 7.7% and 8% of the 182 examined free-living hedgehogs, respectively. In the pool of the isolated dermatophyte strains, Trichophyton erinacei was dominant (29.9%), followed by Trichophyton mentagrophytes (17.9%), Trichophyton benhamiae (13.4%), Nannizzia gypsea (11.9%), Microsporum canis (10.4%), Nannizzia nana (7.5%), Paraphyton cookei (6.0%), and Nannizzia fulva (3.0%). Susceptibility tests revealed the highest activity of luliconazole and the lowest of activity fluconazole among the azole drugs applied. Although terbinafine generally exhibited high efficacy, two Trichophyton mentagrophytes isolates showed resistance to this drug (MIC = 2 µg/ml) resulting from missense mutations in the SQLE gene corresponding to the amino acid substitution Leu393Phe. Summarising, our study has also revealed that such wildlife animals as hedgehogs can be a reservoir of pathogenic human dermatophytes, including harmful strains resistant to commonly used antifungal drugs.
Topics: Animals; Animals, Wild; Antifungal Agents; Arthrodermataceae; Hedgehogs; Humans; Microbial Sensitivity Tests; Poland; Tinea; Trichophyton
PubMed: 34536095
DOI: 10.1007/s00248-021-01866-w -
Infection Jun 2020Fungal infections of the skin, hair, and nails are the largest and most widespread group of all mycoses. Nannizzia nana is a relatively rare etiological factor of...
BACKGROUND
Fungal infections of the skin, hair, and nails are the largest and most widespread group of all mycoses. Nannizzia nana is a relatively rare etiological factor of dermatomycosis in humans, as it usually affects animals, e.g. pigs and boars. In addition to the zoophilic nature, there are also reports of the geophilic reservoir of this dermatophyte species.
OBJECTIVE
In this study, we present symptomatic infections with N. nana aetiology in humans reported recently in Poland. Interestingly, these cases had a non-specific clinical picture and occurred as skin lesions on the neck and foot as well as onychomycosis of the toenails. From the medical history, the patients had no contact with pigs.
METHODS
Diagnostics of these infections was performed with a combination of classical phenotypic and molecular genomic methods. The genomic diversity of the isolates was determined using the MP-PCR method. In vitro antifungal susceptibility tests against itraconazole, ketoconazole, terbinafine and naftifine hydrochloride were also performed.
RESULTS
Nannizzia nana has been identified as an etiological factor of dermatomycosis. Moreover, heterogeneity of the genomes was revealed for the obtained strains. In vitro activities of antifungal agents showed that isolates were susceptible to all tested drugs. The patients were treated with oral terbinafine and topical ketoconazole cream, which led to a complete recovery.
CONCLUSIONS
In conclusion, the cases studied by us may indicate that the infrequency of N. nana infections may not necessarily be related to the low infectivity of this fungal agent, but they are rather associated with misdiagnosis. Furthermore, N. nana reservoirs should also be sought in soil.
Topics: Administration, Oral; Administration, Topical; Adult; Aged; Antifungal Agents; Arthrodermataceae; Dermatomycoses; Diagnosis, Differential; Female; Humans; Ketoconazole; Male; Onychomycosis; Soil Microbiology; Terbinafine; Treatment Outcome
PubMed: 32232786
DOI: 10.1007/s15010-020-01416-5