Original article/Article originalEpidemiology and fungal species distribution of superficial mycoses in Northeast BrazilÉpidémiologie et distribution des espèces fongiques des mycoses superficielles dans le Nord-est du Brésil
Introduction
Dermatomycosis are superficial fungal infections which affect the skin, hair and nails of humans and animals. They affect both male and female patients of all ages and have a worldwide distribution. However, hot and humid climates such as in tropical and subtropical areas contribute to the high prevalence of number of cases in countries from Latin America, Africa and Asia [2], [11], [39].
Superficial fungal infections are related to several predisposing factors, including: climate conditions, people migrations, sports activities, prolonged contact with water, lifestyle, immunological status, drug therapy and age of patients [11]. In addition, life conditions and the environment where people are inserted influence epidemiological characteristics of human infection [11].
The main etiological agents of dermatomycosis are the dermatophytes fungi of the genera Trichophyton, Microsporum and Epidermophyton. The non-dermatophyte agents include other filamentous fungi such as Fusarium and Aspergillus and mainly yeasts belonging to the genera Candida, Malasezzia and Trichosporon [9].
Dermatophytes fungi are filamentous, hyaline, septate and present arthroconidia in their micromorphology. The high incidence of these fungi on epidemiological data of dermatomycosis is influenced by the high production of keratinasis, an important enzyme used for acquisition of nutrients from the environment, but also contributes for fungal invasion of the stratum corneum of epidermis and to degrade keratin of the skin, hair and nails [9]. Therefore, these fungi are known as keratinolytic [6].
Yeasts belonging to the Candida genus are also involved in superficial infections and the main species isolated from dermatomycosis are the Candida parapsilosis species complex, Candida albicans and Candida tropicalis. The lesion occurs mainly in intertriginous areas of the body, such as interdigital, inguinal, intergluteal and inframammary regions as well as nails and periungueal regions [37]. The genus Malassezia comprises lipophilic yeast-like fungi that are part of the normal skin microbiota in humans and warm-blooded animals [15].
The variation in the distribution of dermatomycoses according to the local geography, inspires the conduction of epidemiological studies in order to contribute for the better understanding of patterns of mycological dermatomycoses and etiologic distribution of the most common fungal agents which cause infection in the skin and its annexes. Of note, each species presents peculiarities in terms of body sites and age of patients which they cause disease. Therefore, this study aimed to conduct an epidemiological survey of dermatomycoses derived from patients in a private laboratory located in Northeast Brazil. This data will contribute to increase the discussion on the epidemiology of dermatomycosis in a region of Brazil where this clinical scenario is poorly investigated.
Section snippets
Collection of clinical specimens
Strains were collected from April 2013 to December 2014 at a private clinical laboratory analysis from the city of Natal, Rio Grande do Norte State, Northeast Brazil and sent for further identification at the Laboratory of Medical and Molecular Mycology, Department of Clinical and Toxicological Analysis, Federal University of Rio Grande do Norte. The patients were referred by dermatologists from different clinical ambulatories of the state. During the period of the study, 205 patients of both
Results
In the present study a total of 205 patients were evaluated, while 235 clinical specimens were obtained. A total of 225 samples were analyzed by direct microscopic examination (DME) and culture. Of note, 113 clinical specimens were positive, while 122 were negative for mycological examination. We obtained 42.7% (96 cases) correspondence between direct examination and culture (Table 1). From our positive cases of mycological examination, 73 (64.6%) patients were female, while 40 (35.4%) were
Discussion
In the present study, we observed that among positive cases of mycological examination there was a higher prevalence of female patients with dermatomycosis. It seems that differences in distribution of positive cases of superficial fungal infections between both genders are variable worldwide. For instance, in a retrospective study from 2004 to 2014 performed in China, male patients were predominant (55.3%) rather than female (44.7%) [4]. The same distribution per gender was observed in a
Disclosure of interest
The authors declare that they have no competing interest.
Acknowledgements
We are very grateful to Brazilian Ministry of Education for financial fundings. We also would like to thank Professor Arnaldo Lopes Colombo for donation of reference strains used as controls for fungal identification and to Professor Marcelo Lancellotti for the critical review of the French translation.
References (41)
- et al.
Onychomycosis in Casablanca (Morocco)
J Mycol Med
(2013) - et al.
Onychomycosis-causing yeasts in four Mexican dermatology centers and their antifungal susceptibility to azolic compounds
Rev Iberoam Micol
(2011) - et al.
Mycological profile of onychomycosis in Dakar (Senegal)
J Mycol Med
(2014) - et al.
A study of onychomycosis in patients attending a dermatology center in Tehran, Iran
J Mycol Med
(2015) Methods for the isolation, maintenance and identification of yeasts
- et al.
Onychomycosis in Cali, Colombia
Mycopathologia
(2004) - et al.
Mycological pattern of dermatophytosis in and around Shimla hills
Indian J Dermatol
(2014) - et al.
Onychomycosis in Ceara (Northeast Brazil): epidemiological and laboratory aspects
Mem Inst Oswaldo Cruz
(2005) - et al.
Epidemiology of superficial fungal infections in Guangdong, Southern China: a retrospective study from 2004 to 2014
Mycopathologia
(2016) - et al.
A 7-year survey of superficial and cutaneous mycoses in a public hospital in Natal, Northeast Brazil
Braz J Microbiol
(2011)
The application of MALDI-TOF MS for dermatophyte identification
Ann Parasitol
Epidemiology, etiology and clinical presentation of dermatophytosis in Pernambuco, 1995-2005
Rev Soc Bras Med Trop
Pityriasis Versicolor
An Bras Dermatol
Superficial mycoses at the Hospital do Servidor Público Municipal de São Paulo between 2005 and 2011
An Bras Dermatol
Toenail onychomycosis in a Portuguese geriatric population
Mycopathologia
Superficial fungal infections in a French teaching hospital in Grenoble area: retrospective study on 5470 samples from 2001 to 2011
Mycopathologia
Molecular identification of Candida species isolated from onychomycosis in Shanghai, China
Mycopathologia
Superficial fungal infections: clinical and epidemiological study in adolescents from marginal districts of Lima and Callao, Peru
J Infect Dev Ctries
Sixteen years of pityriasis versicolor in metropolitan area of Porto Alegre, Southern Brazil
Rev Inst Med Trop Sao Paulo
Dermatophytosis: a 16-year retrospective study in a metropolitan area in southern Brazil
J Infect Dev
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