SciELO - Scientific Electronic Library Online

 
vol.80 issue6Fungi preservation in distilled waterBullous mastocytosis in child: case report author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand

Article

Indicators

Related links

Share


Anais Brasileiros de Dermatologia

On-line version ISSN 1806-4841

An. Bras. Dermatol. vol.80 no.6 Rio de Janeiro Nov./Dec. 2005

http://dx.doi.org/10.1590/S0365-05962005000700005 

CLINICAL, EPIDEMIOLOGICAL, LABORATORY AND THERAPEUTIC INVESTIGATION

 

Tinea capitis: epidemiological and ecological aspects of cases observed from 1983 to 2003 in the Botucatu Medical School, state of São Paulo-Brazil*

 

 

Silvio Alencar MarquesI; Rosangela Maria Pires de CamargoII; Aline Helena Gonzáles FaresIII; Renata Mayumi TakashiIII; Hamilton Ometto StolfIV

IFull Professor - Department of Dermatology and Radiation Therapy - Botucatu Medical School – Unesp - Botucatu (SP), Brazil
IIBiologist. Responsible for the Mycology Laboratory, Department of Dermatology and Radiation Therapy - Botucatu Medical School – Unesp - Botucatu (SP), Brazil
III6th-year medical student - Botucatu Medical School – Unesp - Botucatu (SP), Brazil
IVAssistant Professor, Head of the Pediatrical Dermatology Outpatient Clinic - Department of Dermatology and Radiation Therapy - Botucatu Medical School – Unesp - Botucatu (SP), Brazil

Mailling address

 

 


ABSTRACT

BACKGROUND: Tinea capitis is an important fungal infection of both pediatrical and dermatological interest. In Brazil, its prevalence is unknown, and main causal agents are Trichophyton tonsurans n northern and northeastern regions and Microsporum canis in southern and southeastern regions of the country. Knowledge on the most prevalent geni and species has sanitary and therapeutical importance.
OBJECTIVE: To identify dermatophyte species causing Tinea capitis, in a University Hospital that sees patients of the Public Health System (SUS), coming from both urban and rural areas in the interior of State of São Paulo.
METHODS: Samples of clinical cases with suspicion of Tinea capitis, coming from the area under Boucatu Medical School – Unesp’s responsibility, were investigated by means of direct examination and cultivation aimed at identification and isolation of the causal agent.
RESULTS: 594 out of 1,055 suspected cases were confirmed by direct examination, in 364 (61.1%) a causal agent was isolated: M. canis in 88.2%, followed by T. tonsurans (4,7%), T. rubrum (3,3%), M. gypseum (1,9%), T. mentagrophytes Males comprised 55.7% of the cases, and the age range of 0 – 5 years was predominant with 62.6% (p < 0.05).
CONCLUSIONS: M. canis detected prevalence was above the expected for Southeast of Brazil. The frequency of 88.2% may represent an influence of patients coming from the rural areas. These data should be considered for therapeutic decisions.

Keywords: Epidemiology; Microsporum; Tinea capitis


 

 

INTRODUCTION

Tinea capitis is a specific disease of the childhood, with an evolution ranging from acute to chronic, and caused by different dermatophyte fungal species. Knowledge of the epidemiology and ecology of Tinea capitis, egarding a country or its regions, is important for the didactic and sanitary meaning of the information, because of guidance as to screening infectious foci, adoption of preventive measures and for possible infectious agent-dependent therapeutic implications. Prevalence in the general population is theoretically unknown, with reported values that go from 0.52% in Spanish school population2 2.5% in England2 and even 13%, including subclinical infections, in students from Cleveland, USA. Contagious source of Tinea capitis is variable – it can be acquired from other patients or from fomites, in the case of anthropophilic fungi; from animals when infection is caused by zoophilic fungi and, more seldom, from contact with geophilic fungi. The more prevalent infecting species undergo variations from times to times, country to country or even within the regions of a same country, which depends on environmental and ethnical factors, socioeconomical level and populational density.4 In Europe, different surveys have shown Microsporum canis to be the most prevailing species, particularly in Spain, Italy and Greece.5 Anthropophilic species predominate in certain regions of France, England and Sweden.4-6 One of the reasons for this variability in the epidemiological profile observed in Europe could be related to the ethnical composition of the studied population, whose migratory flows coming from Sub-Saharan and Northern Africa and Caribbean contribute to changes in the profile of prevailing infecting species.5,6 In Spain, for instance, occurrence of Tinea capitis caused by anthropophilic species, such as Trichophyton tonsurans, T. soudanense, T. violaceum and Microsporum audoinii, was shown to be statistically higher among immigrant students as compared to natives.1 In England, T. tonsurans was the agent diagnosed in 62 to 91% of instances, depending on the studied population and statistically related to ethnical groups originating from Sub-Saharan Africa or from the Caribbean.4,7 In the American Continent, Tinea capitis varies in prevalence of infecting agents, and is considered to be very important in terms of public health in the US.4,8,9 There, T. tonsurans, an anthropophilic species, is largely predominant, with increasing incidence and rates that reach 88 to 95% of the isolated fungi.4,9 Young African-american males coming from large urban centers, with age between 5 and 18 years, are the most affected, with a relative risk of acquiring Tinea capitis 29.4 times higher than general population.10 T. tonsurans is also the most prevailing species in Canada, with up to 76% of the isolated species.4 M. canis, a zoophilic species, is the predominant causal agent in the other American countries, corresponding, for instance, to 80% of the isolated in Mexico11 and 60% in Argentina.12 In Brazil, various studies, shown in chart 1, have registered a higher frequency of T. tonsurans northern and northeastern states and M. canis in southern and southeastern states.13-21 T. schoenleinii infection, which causes tinea favosa, has been shown to be quite rare in the cited regions and countries.22

This had the goal of adding up epidemiological data on the matter, based on data obtained at the Dermatology Department at Botucatu Medical School-Unesp (Dermatology-FMB), which sees both urban and rural population coming from the interior of the State of São Paulo.

 

PATIENTS AND METHODS

In the period comprised between January 1984 and December 2003, data of patients seen at the Dermatology Outpatient Clinic - FMB with clinical suspicion of Tinea capitis, were gathered. Hair, trimmed hair or scale samples from the suspected damaged area were collected and sent to the Medical Mycology Laboratory at the same service. Mycological diagnosis was made by analysis of the biological specimen, treated with 20% KOH and submitted to direct microscopic examination and culture in a cloranphenicol and actidione (Mycosel®) -containing Sabouraud dextrose medium, kept under room temperature for at least 20 days. In positive cultures, morphological features, such as color, surface and back of the colony, were observed. Micromorphological mycelium and conidia features, such as shape, arrangement, distribution and number of internal cells in the macroconidia, were examined under lactophenol cotton blue staining. Whenever necessary, microcultivation in slides or use of potato agar to stimulate sporulation were carried out to confirm genus and species. In vitro hair perforation techniques and urease biochemical assays were also used whenever necessary. Obtained data were analyzed according to relative frequency of the various dermatophyte species, in the set of cases and according to gender and age ranges of the studied cases. Chi-square test was used to verify frequency differences among the various agents, considering 5% as the significance level. Fischer’s Exact Test was used for analysis of expected frequencies lower than five.

 

RESULTS

During the studied period, 1,085 samples corresponding to clinical suspicions of Tinea capitis, either from children or adults, were sent to the laboratory (Figures 1 and 2). Out of these, 596 (54.9%) were confirmed by means of culture or direct microscopic inspection. In 364 samples (61.1%), cultivation of the etiologic agent was possible. The most frequent dermatophyte species was M. canis, corresponding to 88.2% of isolated species (Figures 3 and 4). M. canis was predominant in both genders, particularly in males (p < 0.05) and it the different studied age ranges, except for those cases of tinea capitis observed in adolescents and adults. T. tonsurans with 4.7% of the isolated species, was the second most frequent, followed by T. rubrum (3,3%), M. gypseum (1,9%), T. mentagrophytes (1,6%) and Trichophyton spp. (0,8%) (Table 1). The majority of cases, n=35prevailed, with 91.3% of the identified species. In this same age range, males corresponded to 58.2% of the cases (data not shown). In the whole set of patients, those in the age range of 0-5 years, n=228 (62.8%), significantly prevailed in comparison to those above 5 years of age (p < 0.05). Frequency of M. canis was higher (p < 0.05) among patients of 0-5 years of age when compared to those above 5. On the other hand, frequency of T. rubrum and T. mentagrophytes was statistically higher in those patients over 5 years of age (p < 0.05), when compared to frequencies in patients below this age range (Table 3). Patients who were over 20 years old comprised only 7 cases (1.9%), five of which were females, all related to some kind of systemic immunosuppression, particularly that associated with systemic lupus erythematosus (three cases). Agents identified in those case are decribed on table 2. Agents identified in those case are decribed on table 2. Relative frequency of M. canis increased in every five-year period since 1984, i.e., no decrease relative to T. tonsurans was observed.

 

 

 

 

 

 

 

 

DISCUSSION

The present paper identifies Tinea capitis epidemiological profile prevailing in the interior of the State of São Paulo, according to the geographical area under the responsibility of the Botucatu Medical School Hospital-Unesp, which sees patients of the Public Health System (SUS) coming from both rural and urban areas. Besides adding up information to brazilian Tinea capitis etiological profile, the importance of the obtained data and their impact reflect not only on therapeutic decision-making, but also on epidemiological and sanitary reasoning at the regional level this study belongs to. As to therapeutics, it can still be said that griseofulvin is the golden standard for the treatment of Tinea capitis.23,24 Used ever since 1958, griseofulvin has been established as a safe and effective drug, when prescribed in doses from 20 to 25 mg per kilogram of body weight. However, not always is it well tolerated, due to possible side effects, such as headaches and gastrointestinal disturbances, or even idiosyncratic ones, such as hypersensitivity. Under such circumstances, terbinafin, itraconazol and even fluconazol are alternatives.25 Nevertheless, when the option is made for a drug other than griseofulvin, reports that suggest a smaller sensitivity of M. canis to treatment with terbinafin26,27 have to be considered, that is, when the isolated species is M. canis, decision-making regarding treatment should take into account a differentiated usage time or the possible failure in case terbinafin is the chosen drug. The same clinical reasoning applies when the infecting species is not identified, but the patient comes from a region where epidemiological evidence indicate M. canis as the prevailing organism. Itraconazole, in the dose of 5 mg per kilogram of body weight, seems to be equally effective, be the isolated fungus M. canis or T. tonsurans,28 even though there may be restrictions to its use in virtue of its cost or less experience of its use in children. From the sanitary point of view, isolation of an anthropophilic or zoophilic species implies in different interventions. In Brazil, when T. tonsurans, was the isolated fungus, active search among relatives and others coexisting under the same roof as the reference case showed rates up to 18.8% of subclinical infection, consequently the state of a healthy bearer with contagious potential.29 These considerations point towards the great clinical and sanitary importance of routine etiologic diagnosis is cases of clinical suspicion of tinea capitis.

In the present study, a large predominance of M. canis, was identified, repeating, in a larger scale, findings from other institutions in southern and southeastern regions of the country. The number obtained here may have been influenced by a possible demand from rural areas, which are characteristic of this institution, even though patient provenance was not an object of this investigation. M. canis was predominant, particularly among males and in the age range of 0-5 years of age (Tables 1-3), revealing the intimate contact these children have with pets, potential infecting sources.30 In adult patients, despite the low number of cases, T. rubrum was the most common causal agent, as if indicating an underlying state of systemic immunosuppression. The reason why T. tonsurans predominates in northern and northeastern states of the country is likewise not clear, having it been suggested to be adapted to the environmental conditions of those regions.16 However, one should recognize the climatic variability that exists among those regions and even within regions of a single state, which suggests that this environmental component is not the determining reason. In the U.S., prevalence of T. tonsurans is equally highlighted and is correlated to the African-American community of great urban centers, coexisting in conditions of high domiciliary family density and a socioeconomical level that is lower that country average.9,10 The same is observed in France, the United Kingdom and Sweden (Stockholm).4-7 The nearest reference is that of the city of São Paulo, where T. tonsurans has a prevalence of up to 31.2%,18,19 which indicates and corroborates the theory that advocates interference of high populational densities and presence of immigrant populations in the epidemiological profile of tinea capitis.

 

CONCLUSIONS

A large predominance of Microsporum canis (88.2%) was identified among 364 isolates of tinea capitis at the Department of Dermatology at Botucatu Medical School-Unesp, an institution that traditionally has an important demand from patients coming from the rural areas. Predominance of M. canis was expressive, independent of gender, increasing in five-year periods considered between 1984 and 2003, period under study. Frequency of Trichophyton tonsurans (4,7%) was far lower than expected, even for the Southeastern region of Brazil, but may express the current epidemiological reality of tinea capitis in the interior of the State of São Paulo, data that should be confirmed by similar studies at other institutions.

 

ACKNOWLEDGMENTS

We thank Professor of Statistics José Eduardo Corrente, from the Research Support Group (Grupo de Suporte à Pesquisa – GAP), at Botucatu Medical School-Unesp, for a critical review of the paper.

 

REFERENCES

1. Cuitara MS, Del Palacio A, Pereira M, Noriega AR. Prevalence of undetected Tinea capitis in a prospective school survey in Madrid: emergence of new causative fungi. Br J Dermatol. 1998; 138:658-60.         [ Links ]

2. Hay RJ, Clayton YM, de Silva N. Tinea capitis in south-east London: a new pattern of infection with public health implication. Br J Dermatol. 1996; 135:955-8         [ Links ]

3. Ghannoum M, Ishan BA, Hajjeh R, Cano M, Al-Hasawi, Yearick D, et. al. Tinea capitis in Cleveland: survey of elementary school students. J Am Acad Dermatol. 2003;48:189-93.         [ Links ]

4. Gupta AK, Scummerbell RC. Tinea capitis. Med Mycol. 2000; 38:255-87.         [ Links ]

5. Hay RJ, Robles W, Midgeley G, Moore MK. Tinea capitis in Europe: new perspectives on an old problem. J Eur Acad Dermatol Venereol. 2001; 15:229-33.         [ Links ]

6. Hällgren J, Petrini B, Wahlgren CF. Increasing Tinea capitis prevalence in Stockholm reflects immigration. Med Mycol. 2004; 42:505-9.         [ Links ]

7. Fuller LC, Child FC, Midgley G Higgins EM. Scalp ring-worm in south east London and an analysis of a cohort of patients from a pediatric dermatology department. Br J Dermatol. 2003; 148:985-8.         [ Links ]

8. Lobato MN, Vugia DJ, Frieden IJ. Tinea capitis in California children: A population based study of a growing epidemic. Pediatrics. 1997; 99:551-4.         [ Links ]

9. Foster KW, Ghannoum MA, Elewski BE. Epidemiologicsurveillance of cutaneous fungal infection in the United States from 1999 to 2002. J Am Acad Dermatol. 2004:50:748-52.         [ Links ]

10. Tack DA, Fleisher A, Mc Michael A, Feldman S. The epidemic of Tinea capitis disproportionately affects school aged African-Americans. Pediatr Dermatol.1999:16:75.         [ Links ]

11. Bonifaz A. Micologia Médica Básica. 2a ed. México D.F: Mendez; 2002: 35-96.         [ Links ]

12. Davel G, Perrotta D, Canteros C, Carloba S, Rodero L, Brudny M. et al. Multicenter study of superficial mycoses in Argentina. Rev Argent Microbiol. 1999; 31:173-81.         [ Links ]

13. Proença NG, Assumpção SBP. Dermatofitoses nas crianças: estudo de 139 casos. An Bras Dermatol. 1989;64:113-4.         [ Links ]

14. Londero AT, Ramos CD. Agentes de dermatofitoses humanas no interior do Rio Grande do Sul no período de 1960-1987. An Bras Dermatol. 1989; 64:161-4.         [ Links ]

15. Reis, CMS, Gaspar APA, Gaspar NK, Leite RMS. Estudo da flora dermatofitica na população do Distrito Federal. An Bras Dermatol. 1992; 67:103-11.         [ Links ]

16. Brilhante RSN, Paixão GC, Salvino LK, Diógenes MJN, Bandeira SP, Rocha MF G. et al. Epidemiologia e ecologia das dermatofitoses na cidade de Fortaleza: o Trichophyton tonsurans como importante patógeno emergente da Tinea capitis. Rev Soc Bras Med Trop. 2000; 33:417-25.         [ Links ]

17. Fernandes NC, Akiti T, Barreiras MG, Dermatophytoses in chidren: study of 137 cases. Rev Inst Med Trop S Paulo. 2001; 43:83-5.         [ Links ]

18. Ruiz LRB, Zaitz C. Dermatófitos e Dermatofitoses na cidade de São Paulo no período de agosto de 1996 a julho de 1998. An Bras Dermatol. 2001; 76:391-401.         [ Links ]

19. Chimelli PAV, Sofiatti AA, Nunes RS, Martins JEC. Dermatophyte agents in the city of São Paulo, from 1992 to 2002. Rev Inst Med Trop S Paulo 2003; 45:259-63.         [ Links ]

20. Aquino PMLP, Lima EO, Farias NMP. Tinea capitis em JoãoPessoa: visão socioeconômica. An Bras Dermatol. 2003;78:713-7.         [ Links ]

21. Dias T, Fernandes OFL, Soares AJ, Passos XS, Costa M, Hasimoto e Souza LK et al. Tinha do couro cabeludo em crianças de Goiânia, Brasil. Rev Soc Bras Med Trop. 2003; 36:653-5.         [ Links ]

22. Matte SMW, Lopes JO, Melo I.S, Costa Beber AA. A focus of favus due to Trichophyton schoenleinii in Rio Grande do Sul, Brasil. Rev Inst Med Trop S Paulo. 1997; 39:1-3.         [ Links ]

23. Bennett ML, Fleischer AB, Loveless JW, Feldman S.R. Oral griseofulvin remains the treatment of choice for tinea capitis in children. Pediatr Dermatol. 2000; 17:304-9.         [ Links ]

24 Brasil. Ministério da Saúde. Dermatologia na tenção básica. Brasília (DF); Ministério da Saúde; 2002. p.92-3. (Cadernos de Atenção Básica, 9)         [ Links ]

25 Chan YC, Friedlander SF. New treatments for tinea capitis. Curr Opin Infect Dis. 2004; 17:97-103.         [ Links ]

26 Boudrez-Rossellet F, Monod M, Jaccoud S, Frenck E. Efficacy of terbenafine treatment of Tinea capitis in children varies according to the dermatophyte species. Br J Dermatol. 1996; 135:1011-2.         [ Links ]

27 Koumantaki E, Kakourou T, Rallis E, Riga P, Georgalla S. Doubled dose of oral terbinafine is required for Microsporum canis Tinea capitis. Pediatr Dermatol. 2001; 18:339-42.         [ Links ]

28 Gupta AK, Ginter G. Itraconazole is effective in the treatment of Tinea capitis caused by Microsporum canis. Pediatr Dermatol. 2001; 18:519-22.         [ Links ]

29 Souza FHC, Fernandes NC. Tinea capitis por Trichophyton tonsurans em crianças: papel dos portadores assintomáticos. An Bras Dermatol. 2001; 76:179-86.         [ Links ]

30 Bassanesi MC, Conci LA, Souza AP, Severo LC. Fonte de infecção na dermatofitose por Microsporum canis. An Bras Dermatol. 1993; 68:11-3.        [ Links ]

 

 

Mailling address:
Silvio Alencar Marques
Departamento de Dermatologia e Radioterapia
Faculdade de Medicina de Botucatu-Unesp
Tel/Fax: (14)3882-4922
E-mail: smarques@fmb.unesp.br

Received on April 15, 2005.
Approved by the Editorial Council and accepted for publication on October 11, 2005.

 

 

* Work done at Faculdade de Medicina da Universidade Estadual Paulista (Unesp) - Botucatu (SP), Brazil.