Tinea capitis in a dermatology center in the city of Fortaleza, Brazil: the role of Trichophyton tonsurans

Superficial mycoses, a matter of concern: Global and Indian scenario-an updated analysis

Superficial mycoses of skin, nails and hair are among the common fungal infections. They are caused by dermatophytes, non-dermatophyte moulds, yeasts and yeast-like fungi. Such fungal infections are widespread all over the world and are predominant in tropical as well as subtropical regions. Environmental factors, such as warm, humid and pitiable hygienic conditions, are conducive for their growth and proliferation. Although it does not cause mortality, it is known to be associated with excessive morbidity which may be psychological or physical. This affects the quality of life of the infected individuals which leads to a negative impact on their occupational, emotional and social status. Such infections are increasing on a global scale and, therefore, are of serious concern worldwide. This review article covers the global and Indian scenario of superficial mycoses taking into account the historical background, aetiological agents, prevalence, cultural and environmental factors, risk factors, pathogenesis and hygienic practices for the prevention of superficial mycoses.

Epidemiological Characteristics and Risk Factors of Tinea Pedis Disease Among Adults Attending Tikrit Teaching Hospital/ Iraq

BACKGROUND

Tinea pedis is one of the most common skin infections of interdigital toe webspace as well as feet skin and may affect the nail or the hand. It is caused by dermophytes fungi especially Trichophyton species. Direct contact with a contaminated environment or animal is the main mode of transmission. Tinea pedis is more frequent among adults than children and more among those with the previous infection with the disease, diabetes mellites, abnormally increased sweating, and the disease is common among individuals who wear unventilated (occlusive) footwear. Tinea pedis is 2-4 times more common in men than females.

AIM OF THE STUDY

To study the epidemiological characteristics and risk factors of tinea pedis disease.

METHODS

Descriptive study was conducted on patients attending the dermatology outpatient clinic in Tikrit Teaching Hospital, Tikrit, Iraq. The study was done during the period from 1st November 2018-10th June 2019. The sample included 680 persons. The cases were diagnosed clinically and by a direct microscope. The demographic information of patients was obtained according to certain questionnaire design. The study was done to reveal the epidemiology of tenia pedis disease among affected patients.

RESULTS

The frequency of tinea pedis cases among the study sample was 7% (48/ 680). It has been observed that there was no significant association as a result of the difference in gender, body weight, positive family history, history, presence of fungal skin disease, and presence of nail trauma. On the contrary, a significant association was observed as a result of the presence of the young age group, diabetes mellitus, and history of wearing occlusive shoes.

CONCLUSION

The frequency of tinea pedis disease among the study sample was 7%. There was a significant association between age group and the presence of diabetes mellitus disease and wearing occlusive shoes.

Epidemiological investigation and molecular typing of dermatophytosis caused by Microsporum canis in dogs and cats

The objective of the present study was investigate the prevalence of dermatophytes in dogs, cats and environment floor through molecular epidemiology tools to identify the genetic profile of these infectious agents. This was an observational study with cross-sectional surveys design. Sample were collected from the hair and skin of 52 dogs and cats with the clinical suspicion of dermatophytosis, over a period of one year in Maringá, in the state of Paraná, Brazil. Household samples (carpets and floor), were collected from animals that were positive for dermatophytosis by morphological colonies characteristics, and samples of dogs or cats living in the same household as with the positive animals were also collected. After mycological confirmation, molecular typing was performed by random amplified polymorphic DNA (RAPD). Microsporum canis was the unic dermatophyto isolated whose prevalence was 26.9% (14/52) in animals with the clinical suspicion of dermatophytosis and four other animals that lived with positive animals. As some animals had more than one lesion site, there were 22 total positive cultures from samples from animals and another ten from abiotic sources. The majority of the animals that provided positive cultures for M. canis were aged up to five months (77.8%) and were female (66.7%). Molecular typing using the P1 primer revealed genetically distinct profiles in the symptomatic, asymptomatic and environmental animal samples, or the same animal, furthermore, showed that M. canis could have microevolution.

[Tropical dermatology-relevant disorders of the scalp]

People whose ancestors came from tropical regions present specific structural characteristics of their skin and hair, including the scalp region. On the one hand, this is for protection against the challenges of these climatic zones; on the other hand, this may lead to an enhanced sensitivity against certain dermatological diseases, either of autoimmune, chronic inflammatory, infectious, or of mechanical origin. A collection of these are discussed in this article.

Quantitative and structural analyses of the in vitro and ex vivo biofilm-forming ability of dermatophytes

PURPOSE

The aim of this study was to evaluate the in vitro and ex vivo biofilm-forming ability of dermatophytes on a nail fragment.

METHODOLOGY

Initially, four isolates of Trichophyton rubrum, six of Trichophyton tonsurans, three of Trichophyton mentagrophytes, ten of Microsporum canis and three of Microsporum gypseum were tested for production biomass by crystal violet assay. Then, one strain per species presenting the best biofilm production was chosen for further studies by optical microscopy (Congo red staining), confocal laser scanning (LIVE/DEAD staining) and scanning electron (secondary electron) microscopy.

RESULTS

Biomass quantification by crystal violet assay, optical microscope images of Congo red staining, confocal microscope and scanning electron microscope images revealed that all species studied are able to form biofilms both in vitro and ex vivo, with variable density and architecture. M. gypseum, T. rubrum and T. tonsurans produced robust biofilms, with abundant matrix and biomass, while M. canis produced the weakest biofilms compared to other species.

CONCLUSION

This study sheds light on biofilms of different dermatophyte species, which will contribute to a better understanding of the pathophysiology of dermatophytosis. Further studies of this type are necessary to investigate the processes involved in the formation and composition of dermatophyte biofilms.

New Antifungal Agents and New Formulations Against Dermatophytes

A variety of oral and topical antifungal agents are available for the treatment of superficial fungal infections caused by dermatophytes. This review builds on the antifungal therapy update published in this journal for the first special issue on Dermatophytosis (Gupta and Cooper 2008;166:353-67). Since 2008, there have not been additions to the oral antifungal armamentarium, with terbinafine, itraconazole, and fluconazole still in widespread use, albeit for generally more severe or recalcitrant infections. Griseofulvin is used in the treatment of tinea capitis. Oral ketoconazole has fallen out of favor in many jurisdictions due to risks of hepatotoxicity. Topical antifungals, applied once or twice daily, are the primary treatment for tinea pedis, tinea corporis/tinea cruris, and mild cases of tinea unguium. Newer topical antifungal agents introduced include the azoles, efinaconazole, luliconazole, and sertaconazole, and the oxaborole, tavaborole. Research is focused on developing formulations of existing topical antifungals that utilize novel delivery systems in order to enhance treatment efficacy and compliance.

Prevalence of Tinea Capitis Infection Among Primary School Children in a Rural Setting in South-West Nigeria

Dermatophyte infection is a common skin disorder. Tinea capitis, infection of the scalp and hair shaft, is the most common dermatophytosis in children aged between six months and pre-pubertal age. The aim of the study was to determine the prevalence, causative agents and to identify predisposing factors among primary school children in a rural community in Sagamu, Ogun state, Nigeria. This was a descriptive cross sectional study. Interviewer administered questionnaire was used. Following a physical examination, children with a clinical diagnosis of tinea capitis had scalp and hair scrapings for microscopy and culture. Tinea capitis was confirmed in 15.4%. Trichophyton mentagrophyte (51.7%) and Microsporum aoudouinii (20.7%) were the most prevalent organisms in this study. The most common predisposing factors were carrying of objects on the scalp; sharing of hair clippers, scissors, combs, towels and fomites. Low socioeconomic status coupled with overcrowding and poor hygiene was the major determinant of tinea capitis among the children. Tinea capitis remains a common infection among Nigerian school children. Health promotion and health education interventions are recommended to promote good hygiene, better living conditions, early identification and treatment.

Trichophyton tonsurans strains from Brazil: phenotypic heterogeneity, genetic homology, and detection of virulence genes

The objective of this study was to establish the phenotypical and molecular patterns of clinical isolates of Trichophyton tonsurans circulating in the state of Ceará, northeastern Brazil. For this purpose, 25 T. tonsurans strains isolated from independent cases of tinea capitis in children were phenotypically evaluated regarding their macro- and micro-morphological characteristics, vitamin requirements, urease production, and antifungal susceptibility. The molecular characterization was carried out with random amplified polymorphic DNA molecular markers and M13 fingerprinting. The presence of the genes CarbM14, Sub2, CER, URE, ASP, PBL, and LAC, which encode enzymes related to fungal virulence, was also evaluated. Finally, melanin production was assessed through specific staining. The data obtained demonstrated that these T. tonsurans strains have considerable phenotypical variation, although they showed a low degree of genetic polymorphism according to the markers used. The genes CarbM14, Sub2, CER, and URE were detected in all the analyzed strains. The gene LAC was also identified in all the strains, and melanin synthesis was phenotypically confirmed. The strains were susceptible to antifungals, especially itraconazole (GM = 0.06 μg/mL) and ketoconazole (GM = 0.24 μg/mL). Therefore, T. tonsurans strains can present great phenotypical heterogeneity, even in genetically similar isolates. Moreover, the presence of the LAC gene indicates the possible participation of melanin in the pathogenesis of these dermatophytes.

A 7-year survey of superficial and cutaneous mycoses in a public hospital in Natal, Northeast Brazil

In the present study, we determined the frequency of superficial and cutaneous mycoses and their etiologic agents during a 7-year period (2002–2008) in Natal, Brazil. A total of 1,717 specimens of skin, nail, and hair were collected from 1,382 patients with suspected mycoses lesions and were then subjected to direct microscopy and culture.

The changing face of Microsporum spp infections

Significant changes in epidemiology, etiology, and the clinical pattern of mycotic infections caused by Microsporum spp have been observed in recent years. Fungal infections caused by M canis, followed by M gypseum and M hominis, involving skin and its appendages, represent one of the most common diseases worldwide and a recalcitrant problem in dermatology that demands appropriate diagnostic and treatment strategies. The most striking clinical phenomena of superficial and kerion and other forms of tinea, such as tinea capitis, fungal infections of the glabrous skin (tinea pedis, manus, cruris et corporis), and even onychomycosis due to Microsporum spp are described, with emphasis on the changes that have occurred in the last decade. The data on significant differences in the prevalence and clinical pattern of the fungal skin infections caused by Microsporum spp today compared with the data at the beginning of the epidemic breakout might still be rather controversial, depending also on the patients' lifestyle and geography. In general, physicians should be aware of the clinical spectrum of mycotic infections due to Microsporum spp to avoid mistakes in identifying the fungal etiology and to provide patients with the proper therapy.

[Epidemiological correlation between keratinophilic fungi isolated from soil and dermatomycosis agents]

This study had the aim of isolating and identifying keratinophilic fungi from soil and correlating them with dermatomycosis agents. According to our results, the predominance of Trichophyton tonsurans as a dermatomycosis agent among children in the city of Recife, PE, is probably due to children's greater contact with soil.

The emergence of Trichophyton tonsurans in Port-au-Prince, Haiti

The occurrence of the anthropophilic dermatophyte Trichophyton tonsurans as a frequent causative agent of tinea capitis in several developed countries has been associated with a global rise in its isolation during recent years. While T. tonsurans was never found in Haiti before 1988, a sharp increase in the number of isolates of this species from scalp lesions began to be observed in 2005 in Port-au-Prince, Haiti. A prospective study was conducted in Port-au-Prince from May to November 2006 of 64 children presenting with tinea capitis at the dermatological outpatient clinic of the university hospital. Forty-five (70%) were male and 19 female (30%), with an average age at presentation of 6.1 years (age range 1-16 years). Direct microscopic examination of scalp hair using 10% potassium hydroxide was positive in 93.8% and culture confirmation was established in 55 cases (85.9%). Five species of dermatophytes were identified, with the anthropophilic dermatophyte T. tonsurans, accounting for the majority or 35 (63.6%) of all cases of tinea capitis. Other dermatophyte species identified included T. mentagrophytes (14.5%), Microsporum audouinii (12.7%), T. rubrum (7.3%) and in one case, the geophilic M. gypseum (1.8%). In two cases caused by T. tonsurans skin involvement on other areas of the body was recorded. The most frequent pathogen in tinea capitis is now T. tonsurans in Port-au-Prince. We speculate that the recent emergence of T. tonsurans in Haiti is linked to the dramatically increasing mobility of Haitian Diaspora.

Characteristics of superficial fungal infections in the Riyadh region of Saudi Arabia

BACKGROUND

The prevalence and characteristics of superficial fungal infections (SFIs) vary with climatic conditions, lifestyle, and population migration patterns. This study was undertaken to determine the characteristics of SFIs amongst patients visiting the dermatology clinic of Riyadh Military Hospital, Riyadh, Saudi Arabia, during the period 2003-2005.

METHODS

One hundred and nineteen patients with confirmed SFI (37 males and 82 females), aged between 5 months and 67 years, were included in this study. The diagnosis of SFI was based on clinical presentation confirmed by laboratory analysis. The type of mycotic pathogen and the site of infection were recorded as a function of age and sex.

RESULTS

Onychomycosis (40.3%) was the most frequent infection, followed by tinea capitis (21.9%), tinea pedis (16%), tinea cruris (15.1%), and tinea corporis (6.7%). Tinea capitis was most prevalent (15.1%) in children (male to female ratio, 1 : 1.57), whereas tinea pedis was most common (11.8%) in adults (male to female ratio, 1 : 2.5). Trichophyton mentagrophytes and Microsporum canis were the most common dermatophytes responsible for tinea infections, and T. mentagrophytes, Candida spp., and Aspergillus spp. were mainly responsible for onychomycosis.

CONCLUSION

The prevalence of SFI was twofold greater in females than males. Children were most commonly affected by tinea capitis, whereas adults generally suffered from tinea pedis. The frequency of onychomycosis was nearly three times higher in adults. This study clearly shows that SFIs are of concern in both genders and in all age groups.

Epidemiologia, etiologia e formas clínicas das dermatofitoses em Pernambuco, 1995-2005

Num total de 1.238 casos de dermatofitoses, ocorridas na Cidade de Recife /PE, observou-se predomínio das tinhas de couro cabeludo (33,7%) e Trichophyton tonsurans (25,5%), entre 1995 e 1999, enquanto as tinhas de pele glabra (35,5%) e Trichophyton rubrum (34%) foram mais freqüentes entre 2000 e 2005. Detectou-se importante redução do Trichophyton mentagrophytes, no último período.

Analysis of the dermatophyte species isolated in the British Isles between 1980 and 2005 and review of worldwide dermatophyte trends over the last three decades

Infections of the skin, hair and nails by dermatophyte fungi are common in developed and developing countries alike. However, the species involved and the resulting clinical entities vary both geographically and with time. We have surveyed 15,333 dermatophytes obtained from primary isolations at the Mycology Reference Laboratory, Bristol, UK from 1980 through 2005. Several striking trends in dermatophyte prevalence were apparent over this period. The relative frequencies of isolations of Microsporum canis (cat and dog ringworm), Trichophyton verrucosum (cattle ringworm), T. mentagrophytes var. mentagrophytes (rodent ringworm) and Epidermophyton floccosum (a cause of human groin and foot infections) all decreased by 90%. Conversely, the contributions of T. tonsurans and T. violaceum (two anthropophilic scalp-infecting species) to total dermatophyte isolations increased by 1000% over the same period. Finally, T. rubrum and T. mentagrophytes var. interdigitale, the two common causes of foot infection comprised 80% of all dermatophytes isolated in 1980 and 90% of isolations in 2005. Similar trends in dermatophyte prevalence were evidenced throughout the British Isles, based on the voluntary reporting of isolations from a large number of British laboratories at 5-yearly intervals over the same period. The implications of these changing patterns of dermatophyte species, and the clinical entities they produce are discussed in the context of a review of worldwide dermatophyte isolations over the last three decades, with emphasis on the causal agents of tinea capitis.

Canine dermatophytosis caused by an anthropophilic species: molecular and phenotypical characterization of Trichophyton tonsurans

Microsporum canis is the most common species isolated from canine and feline dermatophytosis in the world. However, this study reports a rare case of canine dermatophytosis caused by the anthropophilic dermatophyte Trichophyton tonsurans in the city of Fortaleza, Ceará, Brazil. The fungal characterization was performed by classical mycological examination and by genotypical analysis using the restriction enzymes Sau3A, RsaI, DdeI and EcoRI. The phenotypical characteristics were compatible with T. tonsurans. The results obtained in the genotypical analysis were similar to the digestion pattern of the ITS sequences for T. tonsurans strains. In addition, an antifungal susceptibility test was performed with griseofulvin, ketoconazole and itraconazole. The MICs were 0.5 microg ml(-1) for griseofulvin, 0.25 microg ml(-1) for ketoconazole and 1 microg ml(-1) for itraconazole. This study emphasizes the adaptability of anthropophilic fungi such as T. tonsurans to animal conditions.

Incidence of Tinea capitis in São Paulo, Brazil

To determine the incidence of tinea capitis in São Paulo, Brazil, an investigation was performed in Private and Public Pediatrics Service involving 4,500 children from 0 to 15 years old during 5 years (1996-2000). Samples were taken from 132 children with suspected fungal infection of the scalp, for direct microscopy and culture. Tinea of scalp was mycologically confirmed in 112 patients (85%). Males were more affected than females in all age groups. Children below 8 years old accounted for more than 75% of the occurrences. Only three cases of tinea capitis were diagnosed in children from 12 to 15 years of age. Tinea capitis was prevalent in 103 cases (91.96%); inflammatory kerion type lesions were diagnosed in 9 patients (8.04%). Microsporum canis (70.5%) and Trichophyton tonsurans (23.2%) were the most common agents followed by T. mentagrophytes (3.6%), M. gypseum (1.8%) and T. rubrum (0.9%).

Micoses superficiais na cidade de Manaus, AM, entre março e novembro/2003

FUNDAMENTOS: Micoses superficiais estritas são infecções fúngicas que se localizam nas camadas superficiais da pele e seus anexos. As micoses superficiais cutâneas representadas pelas dermatofitoses e candidíases podem ultrapassar a camada córnea da pele. Na região amazônica possuem incidência elevada. OBJETIVOS: Estudar as micoses superficiais, estritas e cutâneas, diagnosticadas sob o ponto de vista epidemiológico e micológico. PACIENTES E MÉTODOS: Pacientes com suspeita clínica de micoses superficiais submetidos a exame micológico no período de março a novembro de 2003 no Laboratório de Micologia Médica/CPCS/INPA. RESULTADOS: Foram realizados 394 exames, tendo 256 apresentado diagnóstico positivo. As micoses mais incidentes foram onicomicoses (135) e pitiríase versicolor (98). Malassezia spp. (77) e Candida spp. (72) foram os agentes fúngicos mais isolados. Tinea capitis apresentou maior ocorrência nos pré-escolares (3), e onicomicoses em adultos (94). O sexo feminino foi o mais acometido (91). Todas as classes sociais foram infectadas, com predominância da C (37). CONCLUSÃO: Onicomicoses e pitiríase versicolor acometeram sobretudo adultos. A Tinea capitis ocorre principalmente, em crianças. As micoses superficiais apresentaram mais incidentes nas mulheres. Malassezia spp. e Candida spp. foram os agentes mais isolados.

Tiña de la cabeza en un adulto. A propósito de un caso

A tinea capitis and tinea faciei case in an elderly female patient with diabetes mellitus type 2 is presented. Her dermatological illness began on her face and later disseminated to her scalp. She received multiple medications which aggravated her condition. The diagnosis was established by means of direct examination and the isolation of Trichophyton tonsurans in culture. Treatment with 200 mg daily dose of itraconazol for two months resulted in clinical and mycological cure.