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Concept: Dermatophytosis

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In the framework of a survey on dermatophytoses, 14,619 clinical specimens taken from outpatients with symptoms suggestive of tinea and referred to a Medical Mycology laboratory in Tehran, Iran, were analyzed by direct microscopy and culture. In total, 777 dermatophyte strains recovered in culture were randomly identified by a formerly established RFLP analysis method based on the rDNA ITS regions. For confirmation of species identification, 160 isolates representing the likely entire species spectrum were subjected to ITS-sequencing. Infection was confirmed in 5,175 collected samples (35.4%) by direct microscopy and/or culture. Tinea pedis was the most prevalent type of infection (43.4%), followed by tinea unguium (21.3%), tinea cruris (20.7%), tinea corporis (9.4%), tinea manuum (4.2%), tinea capitis (0.8%) and tinea faciei (0.2%). Trichophyton interdigitale was the most common isolate (40.5%) followed by T. rubrum (34.75%), Epidermophyton floccosum (15.6%), Microsporum canis (3.9%), T. tonsurans (3.5 %) and M. gypseum (0.5%). Other species included M. ferrugineum, T. erinacei, T. violaceum, T. schoenleinii, and a very rare species T. eriotrephon (each one 0.25%). The two strains of T. eriotrephon isolated from tinea manuum and tinea faciei are the second and third reported cases worldwide. Application of DNA-based methods is an important aid in monitoring trends in dermatophytosis in the community.

Concepts: Biology, Trichophyton rubrum, Onychomycosis, Dermatophyte, Fungal diseases, Terbinafine, Mycosis-related cutaneous conditions, Dermatophytosis

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Superficial fungal infections due to dermatophytes are common over the world and their frequency is constantly increasing. The aim of our study was to discuss fungal infections with frequency of occurrence, clinical stages and aetiology in patients admitted to dermatological ward and microbiological laboratory of the specialist hospital in Krakow. Investigations performed between 1995 and 2010 included the group of 5333 individuals. Dermatophyte infections, confirmed by culture, were revealed in 1007 subjects (18.9%), i.e. in 553 males and 454 females. The most frequent clinical forms of infections were tinea unguium and tinea pedis, caused mainly by Trichophyton rubrum and by Trichophyton mentagrophytes. Tinea corporis, tinea manuum, tinea capitis and tinea cruris constituted a small percentage of infections and the main aetiological factors of these dermatomycoses were also T. rubrum and T. mentagrophytes. Between 1995 and 2000 there were stated small differences in the number of isolated strains of dermatophytes in comparison with the number of examined patients. Since 2006 there has been observed a decrease in number of patients in our hospital with suspected fungal infections, but per cent of positive cultures has remained unchanged in comparison with earlier period.

Concepts: Trichophyton rubrum, Onychomycosis, Athlete's foot, Dermatophyte, Fungal diseases, Terbinafine, Mycosis-related cutaneous conditions, Dermatophytosis

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Tinea infections are caused by dermatophytes and are classified by the involved site. The most common infections in prepubertal children are tinea corporis and tinea capitis, whereas adolescents and adults are more likely to develop tinea cruris, tinea pedis, and tinea unguium (onychomycosis). The clinical diagnosis can be unreliable because tinea infections have many mimics, which can manifest identical lesions. For example, tinea corporis can be confused with eczema, tinea capitis can be confused with alopecia areata, and onychomycosis can be confused with dystrophic toenails from repeated low-level trauma. Physicians should confirm suspected onychomycosis and tinea capitis with a potassium hydroxide preparation or culture. Tinea corporis, tinea cruris, and tinea pedis generally respond to inexpensive topical agents such as terbinafine cream or butenafine cream, but oral antifungal agents may be indicated for extensive disease, failed topical treatment, immunocompromised patients, or severe moccasin-type tinea pedis. Oral terbinafine is first-line therapy for tinea capitis and onychomycosis because of its tolerability, high cure rate, and low cost. However, kerion should be treated with griseofulvin unless Trichophyton has been documented as the pathogen. Failure to treat kerion promptly can lead to scarring and permanent hair loss.

Concepts: Antifungal drug, Onychomycosis, Athlete's foot, Fungal diseases, Griseofulvin, Terbinafine, Mycosis-related cutaneous conditions, Dermatophytosis

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Infections caused by Trichophyton rubrum are very common in dermatological disease. It most often appears as superficial cutaneous mycosis, such as tinea manuum, tinea pedis, and tinea corporis. However, deep infection caused by T. rubrum was rarely reported. We describe a case of mixed type of deep infection caused by T. rubrum in a 45-year-old man with no significant immunodeficiency. This patient had a history of onychomycosis on the toenails without regular treatment for nearly 6 years. And, he had erythema, papule, and nodules on the submandibular area, neck, and chest for almost 1 year. After treated with intravenous infusion of cefotiam for 2 weeks, the lesion aggravated. The fungal direct microscopic examination of pyogenic fluid was positive, and the fungal cultures that produced reddish-brown and yellow pigment showed cottony, wooly, and white colony. After the DNA sequencing, it was identified as T. rubrum. We gave the patient oral terbinafine 250 mg per day and bifonazole cream for external use. Six months later, the patient’s skin lesion was disappeared, and healthy nail growth was seen in two-thirds of nail bed. The terbinafine is effective against deep infection caused by T. rubrum.

Concepts: Trichophyton rubrum, Onychomycosis, Athlete's foot, Fungal diseases, Terbinafine, Trichophyton, Dermatophytosis, Tinea corporis

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Microsporum gypseum is a geophilic dermatophyte that colonises keratinous substances in the soil. Fur-bearing animals carry this dermatophyte but are rarely infected. Human infection can be acquired from the soil, carrier or infected animals, and rarely other humans. M gypseum is an uncommon cause of cutaneous infection in humans and typically manifests as tinea corporis, tinea barbae, and tinea capitis. Onychomycosis is rarely caused by M gypseum.

Concepts: Mammal, Dermatophyte, Fungal diseases, Microsporum, Terbinafine, Mycosis-related cutaneous conditions, Dermatophytosis, Tinea corporis

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Cutaneous infections and infestations are common among children and adolescents. Ectoparasitic infestations affect individuals across the globe. Head lice, body lice, scabies, and infestations with bed bugs are seen in individuals who reside in both resource poor areas and in developed countries. Superficial cutaneous and mucosal candida occur throughput the life cycle. Dermatophyte infections of keratin-containing skin and skin structures result in tinea capitis (scalp), tinea corporis (body), tinea pedis (foot), and tinea unguium (nails). Less frequent endemic fungal infections such as blastomycosis, coccidiodomycosis, and histoplasmosis may present with skin findings. This article will describe the epidemiology and transmission of these conditions as well as their clinical manifestations. The approach to diagnosis will be addressed as well as primary prevention and current therapies.

Concepts: Fungus, Onychomycosis, Dermatophyte, Fungal diseases, Terbinafine, Itraconazole, Mycosis-related cutaneous conditions, Dermatophytosis

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This study aims to improve characteristics of Piper regnellii extract to make it applicable in formulations to treat dermatophytosis, also known as ringworm.

Concepts: Antifungal drug, Ringworm, Dermatophytosis

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According to epidemiological, clinical and mycological criteria, it has long been admitted that the Trichophyton mentagrophytes species includes two varieties: a zoophilic variety (var. mentagrophytes) and an anthropophilic variety (var. interdigitale) that involve the upper and the lower part of the body, respectively. The further application of molecular techniques to the characterization of dermatophyte strains showed that this classification is unreliable. The aim of our study was to assess the usefulness of PCR-RFLP (restriction fragment length polymorphism) and sequencing in the characterization of T. mentagrophytes strains taken from Tunisian patients. The study was carried out in 2008 in the laboratory of Parasitology-Mycology of Farhat Hached University Hospital, Sousse, Tunisia. A total of 133 strains were isolated from 133 patients addressed to the laboratory for dermatological lesions very evocative of dermatomycosis. Eighty strains were isolated from lesions located on the lower part of the body (onychomycosis, tinea pedis) and 53 strains from the upper part of the body (tinea capitis, tinea corporis). All strains were submitted to mycological examination (direct microscopic examination and culture on Sabouraud medium) and further investigated by using RFLP analysis of the PCR-amplified ITS1-5.8 s-ITS2 region of the ribosomal DNA and the MvaI restriction enzyme. In addition, 62 strains were further submitted to a sequencing of the ITS1-5.8 s-ITS2 region. On the basis of mycological criteria, all strains were diagnosed as T. mentagrophytes. All strains produced the same RFLP pattern and were identified as T. mentagrophytes interdigitale regardless of the location of lesions. Out of the 62 sequenced strains, 16 were found anthropophilic and 46 were zoophilic. In conclusion, all strains provisionally diagnosed as T. mentagrophytes on the basis of mycological criteria were shown to belong to T. interdigitale by using PCR-RFLP and sequencing irrespective of the site of lesions. The predominance of zoophilic strains needs further investigation.

Concepts: DNA, Molecular biology, Biology, Biotechnology, Restriction fragment length polymorphism, Fungal diseases, Terbinafine, Dermatophytosis

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Dermatophytosis, commonly known as ringworm, is a superficial fungal skin disease and zoonosis. Pythium oligandrum is a micromycete with mycoparasitic properties that is used in agriculture to control fungal infections on plants. Formulations containing P oligandrum were also developed for the treatment of dermatophytoses, but only several case studies have been published. In order to document the process in simplified conditions in vitro, we investigated the effectiveness of P oligandrum against three pathogenic dermatophytes common in domestic animals.

Concepts: Scientific method, Fungus, Kingdom, Onychomycosis, Fungal diseases, Ketoconazole, Ringworm, Dermatophytosis

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Cutaneous infections with Trichophyton species of Arthroderma (A.) benhamiae are increasingly being detected in Germany. This dermatophyte typically causes tinea corporis, tinea faciei or tinea capitis with in part heavy clinical manifestation like kerion celsi. In special cases diagnosis and therapy can be difficult. In this article, four clinical cases are presented, whereby attention is given to special clinical situations and therapeutic aspects with regard to Trichophyton species of A. benhamiae: Case 1: Kerion celsi by in a 6-year-old boy; Case 2: Deep trichophytia at the mons pubis in a 32-year-old man working in a pet shop and his 27-year-old female partner; Case 3: Tinea manuum in a 7-year-old girl; Case 4: Tinea corporis in an 8‑year-old girl.

Concepts: Medicine, Female, Pubis, Boy, Fungal diseases, Mycosis-related cutaneous conditions, Mons pubis, Dermatophytosis