Tinea capitis is a dermatophyte infection common among prepubertal children in sub-Saharan Africa and mainly caused by Trichophyton and Microsporum species. Accurate identification is challenging as conventional methods like culture and microscopy are slow and mostly based on morphological characteristics, which make them less sensitive and specific. Modern molecular methods, like polymerase chain reaction (PCR) assays, are gaining acceptance and are quick as well as accurate. The aim of this study was to investigate the clinical patterns of tinea capitis and to accurately identify the most common causative dermatophytes affecting the scalps of children aged 1 to 16 years attending the Skin Clinic at Mbarara University of Science and Technology (MUST), Mbarara, Uganda, East Africa, using both conventional mycological methods and PCR-ELISA for detection of dermatophyte DNA. One hundred fifteen clinical samples from children from Western Uganda attending the MUST Skin Clinic with a clinical diagnosis of tinea capitis were analyzed. T. violaceum was identified as the most common causative agent, followed by M. audouinii, T. soudanense, and T. rubrum. The early identification of the causative agent of tinea capitis is a prerequisite for the effective management of the disease, the identification of probable source and the prevention of spreading. Children with tinea capitis in Western Uganda should be treated by systemic therapy rather than topical preparations to ensure high cure rates as the most common causative dermatophytes T. violaceum exhibits an endothrix rather than ectothrix invasion of the hair follicle.

We describe emergomycosis in a patient in Uganda with HIV infection. We tested a formalin-fixed, paraffin-embedded skin biopsy to identify Emergomyces pasteurianus or a closely related pathogen by sequencing broad-range fungal PCR amplicons. Results suggest that emergomycosis is more widespread and genetically diverse than previously documented. PCR on tissue blocks may help clarify emergomycosis epidemiology.

Besides dermatophytoses, a broad range of cutaneous infections due to yeasts and moulds may occur in subtropical and tropical countries where they can affect travellers. Not to be forgotten are endemic occurring dimorphic or biphasic fungi in countries with hot climate, which cause systemic and secondary cutaneous infections in immunosuppressed and immunocompetent people. In the tropics, the prevalence of pityriasis versicolor, caused by the lipophilic yeast Malassezia spp., is about 30-40 %, in distinct areas even 50 %. Increased hyperhidrosis under tropical conditions and simultaneously humidity congestion have to be considered as significant disposing factors for pityriasis versicolor. In tropical countries, therefore, an exacerbation of a preexisting pityriasis versicolor in travellers is not rare. Today, mostly genital yeast infections due to the new species Candida africana can be found worldwide. Due to migration from Africa this yeast pathogen has reached Germany and Europe. Eumycetomas due to mould fungi are rarely diagnosed in Europe. These deep cutaneous mould infections are only found in immigrants from African countries. The therapy of eumycetoma is protracted and often not successful. Cutaneous cryptococcoses due to the yeast species Cryptococcus neoformans and Cryptococcus gattii occur worldwide; however, they are found more frequently in the tropics. Immunosuppressed patients, especially those with HIV/AIDS, are affected by cryptococcoses. Furthermore, Cryptococcus gattii also causes infections in immunocompetent hosts in Central Africa, Australia, California, and Central America.Rarely found are infections due to dimorphic fungi after travel to countries where these fungal pathogens are endemic. In individual cases, cutaneous or lymphogenic transferred sporotrichosis due to Sporothrix schenkii can occur. Furthermore, scarcely known is secondary cutaneous coccidioidomycosis due to Coccidioides immitis after travelling to desert-like endemic regions in southwestern states of the United States and in Latin America, where primary respiratory infection due to this biphasic fungus can be acquired. The antifungal agent itraconazole is the treatment of choice for sporotrichosis and coccidioidomycosis. Talaromyces marneffei-until recently known as Penicillium marneffei-is only found in Southeastern Asia. Mycosis due to this dimorphic fungus has to be considered as an AIDS-defining opportunistic infection. After hematogeneous spread, Talaromyces marneffei affects the skin and mucous membranes of the mouth. Amphotericin B and itraconazole can be used for therapy.

Today, tropical and travel-related dermatomycoses must be increasingly anticipated to present in dermatological offices and clinics. Skin infections due to dermatophytes or other fungi may occur after a journey in countries with a high prevalence for the respective causative fungal pathogen, e.g., tinea corporis due to Trichophyton soudanense. Otherwise, more frequently, single infections and even localized outbreaks due to "exotic" or "imported" pathogens of dermatophytoses occur. These epidemics are observed in childcare facilities in Germany and in other European countries. Source of infection are immigrants from Africa and sometimes from Asian countries. Furthermore, African children, and sometimes also adults, are often only asymptomatic carriers of such anthropophilic dermatophytes. Outbreaks of dermatophyte infections with one and more affected children and also adult staff and teachers due to Trichophyton violaceum or Microsporum audouinii in kindergartens and schools are not a rarity these days. Further tropical and travel-associated dermatophytes are Trichophyton tonsurans, Trichophyton schoenleinii, and Trichophyton concentricum. Tinea capitis should be treated in a species-specific manner. Griseofulvin is the treatment of choice for infections due to Microsporum species. In contrast, tinea capitis due to Trichophyton species has to be treated by terbinafine, however, because the agent is not approved for children in Germany, only after receiving written consent of parents. Alternatives are fluconazole and itraconazole. Onset and aggravation of tinea pedis during travel has its origin in a preexisting neglected fungal infection of the feet. In the tropics, exacerbations and secondary bacterial complications of tinea pedis develop under distinctly promoting conditions.

The anthropophilic dermatophyte T. violaceum represents the most frequent cause of tinea capitis in western Uganda. For successful management oral antifungal therapy is necessary together with supportive topical treatment.

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