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Concept: Mycosis-related cutaneous conditions

28

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

28

Trichophyton rubrum var. raubitschekii is a rare anthropophilic dermatophyte isolated around the world from tinea corporis, tinea cruris, tinea pedis and tinea unguium. In this study, the isolation rate of T. rubrum var. raubitschekii was studied in 200 cases of tinea pedis and tinea unguium in Japan. The 200 clinical isolates were shown to be of downy type as their colonies on Sabouraud’s dextrose agar were white to cream, suede-like to downy, with a yellow-brown to wine-red reverse, and they produced few macroconidia. The type strain of T. rubrum var. raubitschekii (CBS 100084) and one clinical isolate (KMU 8337; isolated at Kanazawa) of downy type tested positive for urease, but the reference strain of T. rubrum (CBS 392.58) and the remaining 199 clinical isolates tested negative. Further epidemiological investigations are required to study human cases of infection with the granular type of T. rubrum and T. rubrum var. raubitschekii in Japan.

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

27

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

25

Dermatophytosis in individuals with human immunodeficiency virus infection seems to manifest with atypical, multiple, or extensive lesions more frequently. In addition, there are reports of presentations with little inflammation, called anergics. Less common etiologic agents have been isolated in these individuals, such as Microsporum species. To describe clinical aspects and etiologic agents of dermatophytosis in individuals with human immunodeficiency virus (HIV) infection. Patients with clinical diagnosis of dermatophytosis underwent scarification for mycological diagnosis through direct microscopic examination and fungal isolation in culture on Sabouraud dextrose agar. Sixty individuals had a clinical hypothesis of dermatophytosis. In 20 (33.3%) of the 60 patients, dermatophytosis was confirmed through a mycological study. Tinea corporis, diagnosed in 14 patients, was the most frequent clinical form, followed by tinea unguium in 7, tinea cruris in 5, and tinea pedis in 1 patient. Most of the lesions of tinea corporis were anergic. Five patients with tinea unguium had involvement of multiple nails, with onychodystrophy as the predominant subtype. Multiple cutaneous lesions occurred in 3 patients and extensive cutaneous lesions in 4. Regarding the agent, Trichophyton rubrum was the most commonly isolated. The high occurrence of anergic skin lesions and involvement of multiple nails, especially as onychodystrophy, corroborates the hypothesis that atypical, disseminated, and more severe presentations are common in individuals with HIV infection. However, no Microsporum species was isolated even in atypical, extensive, or disseminated cases, in disagreement with previous reports. Therefore, the approach of squamous lesions in HIV-positive patients must include a mycological study, in view of the possibility of anergic dermatophytosis, to promote the introduction of a suitable therapeutic agent.

Concepts: HIV, AIDS, Immune system, Infectious disease, Cytomegalovirus, Onychomycosis, Fungal diseases, Mycosis-related cutaneous conditions

25

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

3

We recently developed a mass spectrometry (MS) procedure based on the detection of a serum disaccharide (MS-DS) in patients with invasive candidiasis (IC). Here, we compare the performance of MS-DS for the diagnosis of IC, invasive aspergillosis (IA) and mucormycosis (MM) with commercially available antigen detection tests.

Concepts: Immune system, Bacteria, Candida albicans, Fungal diseases, Mycosis-related cutaneous conditions

2

Fungal infections represent a major burden in the critical care setting with increasing morbidity and mortality. Candidiasis is the leading cause of such infections, with C. albicans being the most common causative agent, followed by Aspergillosis and Mucormycosis. The diagnosis of such infections is cumbersome requiring increased clinical vigilance and extensive laboratory testing, including radiology, cultures, biopsies and other indirect methods. However, it is not uncommon for definitive evidence to be unavailable. Risk and host factors indicating the probability of infections may greatly help in the diagnostic approach. Timely and adequate intervention is important for their successful treatment. The available therapeutic armamentarium, although not very extensive, is effective with low resistance rates for the newer antifungal agents. However, timely and prudent use is necessary to maximize favorable outcomes.

Concepts: Candida albicans, Candidiasis, Antifungal drug, Athlete's foot, Fluconazole, Griseofulvin, Ketoconazole, Mycosis-related cutaneous conditions

0

A cross-sectional descriptive study was conducted at a dermatology referral centre in Bogotá to estimate the frequencies and aetiologies of mycoses in the population under 18 years of age attending the medical mycology laboratory over a 13-year period (2000-2012). A total of 1337 samples from 1221 patients were evaluated, involving direct examination and culture for 1279 samples, direct examination alone for 50 and culture alone for 8. During the study period, dermatophytosis was diagnosed via culture in 537 cases (40.1%). The most common aetiological agents were Trichophyton rubrum (235 cases), Microsporum canis (177), Trichophyton mentagrophytes (74) and Microsporum gypseum (22). Pityriasis versicolor was found in 31 cases (5.1%), Candida spp. were found in 17 cases, and non-dermatophyte moulds were confirmed by a second sample in 6 cases (3 cases involving Fusarium spp., 2 Neoscytalidium dimidiatum and 1 Acremonium spp.). Additionally, white piedra was diagnosed in 4 cases (0.7%), and tinea nigra in 2 cases (0.3%). Regarding subcutaneous mycoses, 14 cases of sporotrichosis were identified. The results from this study confirm the predominance of dermatophytosis in the paediatric population. T. rubrum and M. canis were the main aetiological agents. We found a few cases of onychomycosis by non-dermatophyte moulds. Sporotrichosis was the only subcutaneous mycosis diagnosed during the study period. This article is protected by copyright. All rights reserved.

Concepts: Medicine, Trichophyton rubrum, Onychomycosis, Fungal diseases, Mycosis, Microsporum, Mycosis-related cutaneous conditions

0

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

0

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