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Medical Mycology Journal 2023Trichophyton tonsurans infection has been prevalent among individuals involved in contact sports in Japan since about 2000. The present review focuses on its diagnosis,... (Review)
Review
Trichophyton tonsurans infection has been prevalent among individuals involved in contact sports in Japan since about 2000. The present review focuses on its diagnosis, molecular epidemiology, drug susceptibility, and infection control. The most commonly observed lesions of T. tonsurans, an anthropogenic dermatophyte, are tinea corporis and tinea capitis. However, the presence of asymptomatic carriers must be considered for infection control. Genotypic epidemiology using restriction fragment length polymorphisms (RFLP) in the non-transcribed spacer (NTS) region of the ribosomal RNA gene showed a lack of diversity of genotypes, and only the NTS I genotype is detected at present. In regard to drug susceptibility, terbinafine drug resistance has not been found to be associated with the RFLP genotypes, and it is assumed that there are no terbinafine-resistant strains in Japan. T. tonsurans coexisted with other fungi and bacteria in the scalp of asymptomatic carriers without affecting species diversity. T. tonsurans is an anthropogenic dermatophyte and may be difficult for the human immune system to eliminate. During an infection outbreak, screening of infection and treatment including asymptomatic carriers are essential to eradicate the infection.
Topics: Humans; Tinea; Tinea Capitis; Genotype
PubMed: 37648498
DOI: 10.3314/mmj.23-001 -
Journal of Clinical Medicine Jul 2022Tinea gladiatorum (TG) is a fungal skin infection that occurs among wrestlers and other contact sport athletes with a varied prevalence rate. The most common causative... (Review)
Review
Tinea gladiatorum (TG) is a fungal skin infection that occurs among wrestlers and other contact sport athletes with a varied prevalence rate. The most common causative factor responsible as well for local outbreaks of the infection is an anthropophilic dermatophyte species- (). The purpose of this study was to gather current data about TG, including epidemiology, possible diagnosing methods, clinical features, treatment approaches, and potential prevention techniques. We also performed a systematic review of studies describing TG incidence. The prevalence of the disease varied from 2.4% up to 100%. That wide range of variability forces medical practitioners to update knowledge about TG and points to the fact that it still may be a diagnostic and therapeutic challenge. Spreading awareness among athletes and trainers is one of the most important preventive steps.
PubMed: 35887830
DOI: 10.3390/jcm11144066 -
Frontiers in Microbiology 2021Dermatophytes are a group of molds characterized by the ability to produce keratinases, thereby carving out for themselves specific ecological niches. Their traditional... (Review)
Review
INTRODUCTION
Dermatophytes are a group of molds characterized by the ability to produce keratinases, thereby carving out for themselves specific ecological niches. Their traditional division into three genera, , , and has been expanded to nine and the species in each genus were modified. Dermatophytes are among the most prevalent causes of human and animal mycoses. Their epidemiology is influenced by various factors. These factors may be evolutive such as the predilected environment of the fungus, namely, humans (anthropophilic), animals (zoophilic), or environment (geophilic), is evolutionary and thus may require centuries to develop. Many other factors, however, result from a variety of causes, affecting the epidemiology of dermatophytoses within a shorter time frame.
OBJECTIVE
This review aims at summarizing the factors that have modified the epidemiology of dermatophytoses during the last decades.
RESULTS
Geographic and climatic conditions, demography such as age and gender, migration, socio-economic conditions, lifestyle, and the environment have had an impact on changes in the epidemiology of dermatophytoses, as have changes in the pattern of human interaction with animals, including pets, farm, and wild animals. A typical example of such changes is the increased prevalence of , which spread from Latin America to the United States and subsequently becoming a frequent etiological agent of tinea capitis in Africa, Middle East, and other areas.
CONCLUSION
The comprehension of the epidemiology of dermatophytoses has a major bearing on their prevention and treatment. Since it is undergoing continuous changes, periodic assessments of the most recent developments of this topic are required. This article aims at providing such an overview.
PubMed: 34421872
DOI: 10.3389/fmicb.2021.713532 -
Medical Mycology Jan 2022Trichophyton tonsurans is a cosmopolitan dermatophyte, highly prevalent in Africa, South America, and endemic in North America, where it is mostly related to cases of...
UNLABELLED
Trichophyton tonsurans is a cosmopolitan dermatophyte, highly prevalent in Africa, South America, and endemic in North America, where it is mostly related to cases of tinea capitis. Recently, it was also reported in Chile for the first time in two outbreaks occurred in Santiago. In the present study, we sequenced the variable internal repeat (VIR) region of a Chilean isolate and compared its genotype with those of several global T. tonsurans isolates. The results showed that the Chilean isolate presented a new genotype which was strictly correlated with isolates from Europe, USA and Mexico.
LAY SUMMARY
Trichophyton tonsurans is a fungus able to cause superficial mycosis infecting skin and hair. It is an emerging pathogen worldwide and some cases were recently reported also in Chile for the first time. We investigated by molecular techniques which geographical area could be the source of infections.
Topics: Arthrodermataceae; Chile; Genotype; Humans; Tinea Capitis; Trichophyton
PubMed: 34919706
DOI: 10.1093/mmy/myab077 -
Actas Dermo-sifiliograficas Mar 2008Tinea capitis is a widespread scalp infection in children caused by dermatophytes. In fact, it is the most common cutaneous mycosis in children but is uncommon in... (Review)
Review
Tinea capitis is a widespread scalp infection in children caused by dermatophytes. In fact, it is the most common cutaneous mycosis in children but is uncommon in adults. The disease has been major public health concern for decades. Some factors implicated in infection include poor personal hygiene, crowded living conditions, and low socioeconomic status. It can be caused by any pathogenic dermatophyte except for Epidermophyton floccosum and Trichophyton concentricum. Trichophyton rubrum, the most commonly isolated dermatophyte worldwide, is rarely the causative agent of this infection. Tinea capitis is a classic example of the changing geographic patterns of dermatophytosis. In developed countries, Trichophyton tonsurans is the most common causative agent, whereas in developing countries such as Mexico, the most common agent is Microsporum canis followed by Trichophyton tonsurans. The increasing incidence of tinea capitis warranted a review of the current literature and treatment strategies.
Topics: Antifungal Agents; Humans; Tinea Capitis
PubMed: 18346430
DOI: No ID Found -
Current Medical Mycology 2020is a widely distributed anthropophilic dermatophyte causing different diseases of skin. In the literature limited data are available about the morphogenesis of...
BACKGROUND AND PURPOSE
is a widely distributed anthropophilic dermatophyte causing different diseases of skin. In the literature limited data are available about the morphogenesis of vegetative mycelium of and related anthropophilic dermatophytes. The aim of present study was to describe ultrastructural patterns of development, cellular organellography and septal pore apparatus structure of growing vegetative mycelium of .
MATERIALS AND METHODS
strain RCPFF 214/898 was grown on solid Czapek's Agar (CzA) at 28ºС. For investigation of colonies morphology we used methods of light-, scanning and transmission electron microscopy (SEM and TEM).
RESULTS
Differences in morphogenesis of aerial and substrate hyphae were revealed. Mitochondrial reticulum and fibrosinous bodies were shown in for the first time. The septal pore apparatus in hyphal cells of was comprised Woronin bodies and septal pore plugs. Woronin bodies (0.18 µm), located with 1‒4 near the pore, were spherical, membrane-bound, and had a homogeneous, electron-dense content. The cells of aerial and submerged hyphal cells of contain two nuclei.
CONCLUSION
Mature cells of substrate hyphae appeared more active than comparable cells in the aerial mycelium. During the maturation process, the differences in number and morphology of mitochondria, number of vacuoles, and in the synthesis of different types of storage substances were revealed. Presence of "mitochondrial reticulum" and variable types of storage substances in submerged hyphal cells suggested higher levels of metabolic activity compared to aerial mycelium.
PubMed: 32420507
DOI: 10.18502/cmm.6.1.2508 -
Indian Dermatology Online Journal 2022Tinea pseudoimbricata is a variant of dermatophytosis characterized morphologically by concentric scaly rings resembling tinea imbricata with an culture isolate other...
INTRODUCTION
Tinea pseudoimbricata is a variant of dermatophytosis characterized morphologically by concentric scaly rings resembling tinea imbricata with an culture isolate other than Trichophyton concentricum. To date, no large case report series is available.
AIM
To study the clinical profile and the fungus isolated in patients with tinea pseudoimbricata.
MATERIALS AND METHODS
In this case series, all the patients with tinea imbricata with an isolate other than Trichophyton concentricum were subjected to a detailed history and clinical examination. Scrapings of the scales were investigated with potassium hydroxide examination and culture in Sabouraud Dextrose Agar enriched with cycloheximide and chloramphenicol. The results obtained were tabulated and analyzed.
RESULTS
A total of 42 patients fulfilling the above culture criteria were included in the present study. A majority were in the age group of 21-40 years (54.70%) with a male preponderance (M:F = 2:1). All the patients had abused steroids for more than 4 weeks and had multiple site involvement. Trichophyton tonsurans (42.8%) was the predominant isolate cultured, followed by Trichophyton mentagrophytes.
CONCLUSION
Hence, as per our study, tinea pseudoimbricata is encountered more often nowadays due to the misuse of topical steroids and to diagnose tinea pseudoimbricata culture is mandatory. The morphology of concentric rings is not restricted to Trichophyton concentricum, but can occur with other species depending on the clinical scenario.
PubMed: 35198471
DOI: 10.4103/idoj.IDOJ_832_20 -
Microbiology (Reading, England) Feb 2021Chlamydoconidium-producing strains isolated in Northeastern Brazil have morphological features different from the classic description of this dermatophyte species. This...
Chlamydoconidium-producing strains isolated in Northeastern Brazil have morphological features different from the classic description of this dermatophyte species. This study investigated the phylogenetic relationship of chlamydoconidium-producing strains isolated in Northeastern Brazil. Also, the effect of terbinafine and farnesol on mature biofilms of strains was evaluated. The mass spectra of strains were investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The ITS and LSU loci regions of rDNA and the partial β-tubulin gene were sequenced and the phylogenetic tree was analysed. The effects of terbinafine and farnesol on mature biofilms were evaluated through the analysis of metabolic activity, quantification of biomass and observation by scanning electron microscopy. MALDI-TOF MS spectra of the chlamydoconidium-producing strains differed from the spectrum of the control strain (ATCC 28942), presenting an intense ion peak at 4155 Da. Phylogenetic tree analysis showed that the chlamydoconidium-producing strains isolated in Northeastern Brazil are allocated to a single cluster, differing from strains isolated from other countries. As for mature biofilms, farnesol reduced biomass and metabolic activity by 64.4 and 65.9 %, respectively, while terbinafine reduced the biomass by 66.5 % and the metabolic activity by 69 %. Atypical morphological characteristics presented by chlamydoconidium-producing strains result from phenotypic plasticity, possibly for adaptation to environmental stressors. Also, farnesol had inhibitory activity against biofilms, demonstrating this substance can be explored for development of promising anti-biofilm drugs against dermatophytes.
Topics: Antifungal Agents; Arthrodermataceae; Biofilms; Brazil; DNA, Fungal; DNA, Ribosomal; Farnesol; Fungal Proteins; Humans; Microbial Sensitivity Tests; Phylogeny; Sequence Analysis, DNA; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spores, Fungal; Terbinafine; Tubulin
PubMed: 33427606
DOI: 10.1099/mic.0.001018 -
Antibiotics (Basel, Switzerland) Jan 2021Among the top five human infections requiring medical treatment is dermatitis. Treatment of bacterial and fungal skin infections is usually based on antibiotic therapy,...
Among the top five human infections requiring medical treatment is dermatitis. Treatment of bacterial and fungal skin infections is usually based on antibiotic therapy, which is often ineffective due to the involvement of antibiotic-resistant microbial strains. The aim of this study was to compare the antimicrobial activity of essential oils (EOs) and hydrolates (Hys) extracted from six aromatic plants grown in Italy ( and ) towards fungal (, , and ; , , , and ) and bacterial strains ( MRSA, MSSA, , VRE, and ) potentially pathogenic for human skin. The composition and antimicrobial activity of EOs and Hys were evaluated using the Gas-chromatography mass spectrometry and micro dilution-broth test, respectively. The volatiles' conversion factors (CFs) were calculated to compare the activity of Hys with that of the corresponding EOs. Data show that, although the minimum inhibitory concentration values of EOs are lower than the corresponding Hys, the volatiles contained in Hys are more effective at inhibiting microbial growth because they are active at lower concentrations.
PubMed: 33477717
DOI: 10.3390/antibiotics10010088 -
Frontiers in Microbiology 2022is the most pathogenic type of fungal skin infection. It often invades and grows in a keratin-rich matrix, and lesions include human skin, hair, and fingernails...
is the most pathogenic type of fungal skin infection. It often invades and grows in a keratin-rich matrix, and lesions include human skin, hair, and fingernails (toenails). We designed LAMP primers for and developed a LAMP-Microfluidic chip detection system for . This system detects six common species of in the genus , including , , , , , and . The specificity reached 100%, and the sensitivity could reach about 1 × 10 copies/μl. The entire detection process can be completed within 60 min and does not cross-react with other dermatophytes. The established LAMP-Microfluidic chip detection system has the advantages of simple operation, high specificity, and high sensitivity, and has the potential for clinical application.
PubMed: 36312927
DOI: 10.3389/fmicb.2022.1031388