Tinea faciei incognito due to Trichophyton rubrum as a result of autoinoculation from onychomycosis

[Dermatomycoses: topical and systemic antifungal treatment]

Topical antifungals with activity against dermatophytes include amorolfine, allylamines, azoles, ciclopiroxolamine, and tolnaftate. Polyene antimycotics, such as amphotericin B and nystatin, alternatively, miconazole are suitable for yeast infections of the skin and mucous membranes. For severe yeast infections of the skin and mucous membranes, oral triazole antimycotics, such as fluconazole and itraconazole, are used. Pityriasis versicolor is treated topically with antimycotics, and in severe forms also orally with itraconazole, alternatively fluconazole. Terbinafine, itraconazole and fluconazole are currently available for the systemic treatment of severe dermatophytoses, tinea capitis and onychomycosis. In addition to proven therapeutic regimens, unapproved (off-label use) intermittent low-dose therapies are increasingly being used, particularly in onychomycosis. Oral antimycotics for the treatment of tinea capitis and onychomycosis in children and adolescents can only be used off-label in Germany. In general, any oral antifungal treatment should always be combined with topical antifungal therapy. In tinea corporis and tinea cruris caused by Trichophyton (T.) mentagrophytes ITS (internal transcribed spacer) genotype VIII (T. indotineae), there is usually terbinafine resistance. Identification of the species and genotype of the dermatophyte and resistance testing are required. The drug of choice for T. mentagrophytes ITS genotype VIII dermatophytoses is itraconazole. In individual cases, treatment-refractory onychomycosis may be due to terbinafine resistance of T. rubrum. Here too, resistance testing and alternative treatment with itraconazole should be considered. Therapy monitoring should be carried out culturally and, if possible, using molecular methods (polymerase chain reaction). Alternative treatment options include laser application, and photodynamic therapy (PDT).

[Clinical picture, causative agents and diagnostics of dermatomycoses]

Dermatomycoses affect free skin, hairy scalp, fingernails and toenails. In addition, oral mucosa and genital mucosa can also be affected by fungal infections. The most common pathogens causing skin fungal infections are dermatophytes. They are responsible for, among others, tinea corporis, tinea capitis and onychomycosis (tinea unguium). Mainly anthropophilic dermatophytes are found as pathogens. In the case of tinea capitis-at least in Europe and in German-speaking countries-zoophilic skin fungi must also be considered. Rarely, geophilic dermatophytes can also be isolated. Yeast infections of the skin, mostly caused by Candida albicans, primarily affect the intertriginous skin areas, for example, the groin region, but also the submammary area and the spaces between the fingers and toes. Elderly patients are often affected, but also infants and, in particular, immunocompromised patients. These patient groups are also more frequently affected by oral mucosal infections caused by Candida albicans and other Candida species. Pseudomembranous candidiasis of the oral mucosa and tongue typically affects patients with HIV/AIDS. Mold infections in dermatology are relevant in onychomycosis of the big toenail. The causative agent is usually Scopulariopsis brevicaulis. Cutaneous mold infections are rare and only occur in immunocompromised patients. The mycological diagnosis of dermatomycoses is based on the microscopic, if possible fluorescence-optical detection of fungal hyphae and spores from skin scales, nail shavings and hair roots. The culture detection of dermatophytes, yeasts and molds allows the identification of the causative fungal species, but often fails, especially in patients who have already been treated with antifungal agents. In view of the high sensitivity and specificity of the molecular methods for fungal detection compared to culture, polymerase chain reaction (PCR) must realistically be regarded as the gold standard for dermatophytosis diagnostics. However, it should not be neglected that the three pillars of diagnostics-preparation, culture, PCR-currently deliver the best results.

[Tinea barbae profunda due to Trichophyton mentagrophytes after journey to Thailand : Case report and review]

Tinea barbae represents a very rare dermatophytosis. We report on a tinea barbae profunda following a journey to Southeast Asia. After travel to Thailand, a businessman was affected by a foudroyant proceeding abscessing infection of the upper lip and beard area. The initial therapy with oral acyclovir and oral ciprofloxacin, which later was changed to ampicillin plus sulbactam, intravenously, was unsuccessful. In a biopsy sample, histologically, with Grocott-Gomori's methenamine silver stain, fungal mycelium was apparent in the tissue. Thereupon, terbinafine 250 mg was given for 4 weeks, topically, a 1% ciclopiroxolamine-containing cream. In fungal culture, T. mentagrophytes were found to grow. Meanwhile, the patient's German wife suffered from a tinea faciei. From skin scrapings from the cheek, T. mentagrophytes was also cultivated. This zoophilic dermatophyte was identical with other zoophilic strains of T. mentagrophytes currently found in Germany, which were also acquired in Thailand. The patient had contact with Thai female sex workers who must be considered as a source of infection of the dermatophytosis. There was no animal contact, neither in Thailand, nor in Germany. The infection chain of the dermatophytosis from Thailand probably reached from a female sex worker via the here described patient to his wife in Germany. This pathway of infection has been known for 1 or 2 years, but until now, in Germany, Switzerland, and Austria exclusively via pubogenital infections (tinea genitalis profunda) due to T. mentagrophytes after journeys to Southeast Asia. For treatment, oral antifungal agents should be used, first of all terbinafine, alternatively fluconazole or itraconazole.

[Tinea barbae profunda due to Trichophyton mentagrophytes : Case report and review]

Tinea barbae is a rare dermatomycocis, by definition follicular bound in the beard area of adult men. Manifestation usually starts with erythema accompanied by desquamation. Deeper distribution along terminal hairs leads to folliculitis with formation of pustules and nodes as well as abscesses; fixed adherent yellowish crusts may appear. Frequently there is locoregional swelling of the lymph nodes and occasionally a deterioration of general condition with (sub)febrile temperatures. Often this leads to the initial suspected diagnosis of a bacterial folliculitis barbae or impetigo contagiosa. Tinea barbae is mostly induced by species of the genus Trichophyton (T.). The pathogens are diverse and are mostly zoophilic, sometimes anthropophilic and rarely geophilic dermatophytes. With the help of a specific anamnesis and diagnostic procedure, including mycological examinations, histology and molecular detection of dermatophytes via polymerase chain reaction (PCR), tinea barbae-in our patient induced by T. mentagrophytes-can be rapidly diagnosed. Early initiation and adequate treatment duration lead to restitutio ad integrum.

Increasing Prevalence of Trichophyton rubrum Identified through an Analysis of 115,846 Cases over the Last 37 Years

Trichophyton rubrum is the most common dermatophyte in the world with the highest prevalence in Korea. There are few reports about epidemiological and mycological characteristics of T. rubrum based on long-term, large-scale studies. The purpose of this study was to investigate the clinical and epidemiological characteristics of T. rubrum infections in Korea. We retrospectively investigated with patients' records about the epidemiological and mycological status of 115,846 cases with T. rubrum infection that was mycologically diagnosed at Catholic Skin Disease Clinic from 1979 to 2013. Direct microscopy in 15% KOH solution and culture was done in each case. The annual incidence of patients with T. rubrum infection had been increasing during the period; and of 131,122 patients with dermatophytosis, 115,846 patients (88.35%) had T. rubrum infection. Disease was most prevalent among patients in their twenties in the 1970s and 1980s; in their thirties in the 1990s; in their forties in the 2000s; and in their fifties in the 2010s. The sex ratio was 1.5:1. T. rubrum infection was most commonly seen in summer and was found predominantly in patients living in urban areas. Toe webs were most frequently involved, followed by toenails and groin. This epidemiologic findings provide useful information for prevention of T. rubrum infection and future dermatophytosis prospects.

Mycology - an update. Part 1: Dermatomycoses: causative agents, epidemiology and pathogenesis

Dermatomycoses are caused most commonly by dermatophytes. The anthropophilic dermatophyte Trichophyton rubrum is still the most frequent causative agent worldwide. Keratinolytic enzymes, e.g. hydrolases and keratinases, are important virulence factors of T. rubrum. Recently, the cysteine dioxygenase was found as new virulence factor. Predisposing host factors play a similarly important role for the development of dermatophytosis of the skin and nails. Chronic venous insufficiency, diabetes mellitus, disorders of cellular immunity, and genetic predisposition should be considered as risk factors for onychomycosis. A new alarming trend is the increasing number of cases of onychomycosis - mostly due to T. rubrum - in infancy. In Germany, tinea capitis is mostly caused by zoophilic dermatophytes, in particular Microsporum canis. New zoophilic fungi, primarily Trichophyton species of Arthroderma benhamiae, should be taken into differential diagnostic considerations of tinea capitis, tinea faciei, and tinea corporis. Source of infection are small household pets, particularly rodents, like guinea pigs. Anthropophilic dermatophytes may be introduced by families which immigrate from Africa or Asia to Europe. The anthropophilic dermatophytes T. violaceum, T. tonsurans (infections occurring in fighting sports clubs as "tinea gladiatorum capitis et corporis") and M. audouinii are causing outbreaks of small epidemics of tinea corporis and tinea capitis in kindergartens and schools. Superficial infections of the skin and mucous membranes due to yeasts are caused by Candida species. Also common are infections due to the lipophilic yeast fungus Malassezia. Today, within the genus Malassezia more than 10 different species are known. Malassezia globosa seems to play the crucial role in pityriasis versicolor. Molds (also designated non-dermatophyte molds, NDM) are increasingly found as causative agents in onychomycosis. Besides Scopulariopsis brevicaulis, several species of Fusarium and Aspergillus are found.

Tinea incognito in Korea and its risk factors: nine-year multicenter survey

Tinea incognito (TI) is a dermatophytic infection which has lost its typical clinical appearance because of improper use of steroids or calcineurin inhibitors. The incidence of TI is increasing nowadays. We conducted retrospective review on 283 patients with TI from 25 dermatology training hospitals in Korea from 2002-2010 to investigate the demographical, clinical, and mycological characteristics of TI, and to determine the associated risk factors. More than half (59.3%) patients were previously treated by non-dermatologists or self-treated. The mean duration of TI was 15.0 ± 25.3 months. The most common clinical manifestations were eczema-like lesion, psoriasis-like, and lupus erythematosus-like lesion. The trunk and face were frequently involved, and 91 patients (32.2%) also had coexisting fungal infections. Among 67 isolated strains, Trichophyton rubrum was the most frequently detected (73.1%). This is the largest study of TI reported to date and the first investigational report concerning TI in Korea. We suggest that doctors should consider TI when a patient has intractable eczema-like lesions accompanied by tinea pedis/unguium. Furthermore, there should be a policy change, which would make over-the-counter high-potency topical steroids less accessible in some countries, including Korea.

Onychomycosis: modern diagnostic and treatment approaches

The medical term onychomycosis should be understood as chronic infection of the nails caused by a fungus. The most common causative agents are the dermatophytes and Candida species. The less common are certain types of moulds (nondermatophyte moulds or NDMs). In approximately 60-80 % of the cases, onychomycosis is due to dermatophytes. Among dermatophytes, the most often isolated causative pathogen is Trichophyton (T.) rubrum. Other common species are T. interdigitale (formerly T. mentagrophytes), Epidermophyton floccosum, and T. tonsurans. The most significant yeasts causing onychomycosis are Candida albicans and Candida parapsilosis. Predisposing factors for onychomycosis include mainly diseases such as diabetes mellitus, peripheral vascular arterial disease, chronic venous insufficiency, polyneuropathies of diverse etiologies, and immunosuppression, e.g., myeloproliferative diseases (such as lymphoma and paraproteinemia), HIV/AIDS, etc. Other factors facilitating the fungal infection are frequent trauma in professional sportsmen, often accompanied by excessive perspiration. The diagnostic methods that are often applied in different dermatologic departments and ambulatory units are also different. This precludes the creation of a unified diagnostic algorithm that could be used everywhere as a possible standard. In most of the cases, the method of choice depends on the specialist's individual experience. The therapeutic approach depends mostly on the fungal organism identified by the dermatologist or mycologist. This review hereby includes the conventional as well as the newest and most reliable and modern methods used for the identification of the pathogens causing onychomycosis. Moreover, detailed information is suggested, about the choice of therapeutic scheme in case whether dermatophytes, moulds, or yeasts have been identified as causative agents. A thorough discussion of the schemes and duration of the antifungal therapy in certain groups of patients have been included.

[Fungal nail infections--an update: Part 1--Prevalence, epidemiology, predisposing conditions, and differential diagnosis]

Onychomycosis describes a chronic fungal infection of the nails most frequently caused by dermatophytes, primarily Trichophyton rubrum. In addition, yeasts (e. g. Candida parapsilosis), more rarely molds (Scopulariopsis brevicaulis), play a role as causative agents of onychomycosis. However, in every case it has to be decided if these yeasts and molds are contaminants, or if they are growing secondarily on pathological altered nails. The point prevalence of onychomycosis in Germany is 12.4%, as demonstrated within the "Foot-Check-Study", which was a part of the European Achilles project. Although, onychomycosis is rarely diagnosed in children and teens, now an increase of fungal nail infections has been observed in childhood. More and more, diabetes mellitus becomes important as significant disposing factor both for tinea pedis and onychomycosis. By implication, the onychomycosis represents an independent and important predictor for development of diabetic foot syndrome and foot ulcer. When considering onychomycosis, a number of infectious and non-infectious nail changes must be excluded. While psoriasis of the nails does not represent a specific risk factor for onychomycosis, yeasts and molds are increasing isolated from patients with psoriatic nail involvement. In most cases this represents secondary growth of fungi on psoriatic nails. Recently, stigmatization and impairment of quality of life due to the onychomycosis has been proven.

Tinea incognito

Tinea incognito was first described 50 years ago. It is a dermatophytic infection with a clinical presentation modified by previous treatment with topical or systemic corticosteroids, as well as by the topical application of immunomodulators such as pimecrolimus and tacrolimus. Tinea incognito usually resembles neurodermatitis, atopic dermatitis, rosacea, seborrheic dermatitis, lupus erythematosus, or contact dermatitis, and the diagnosis is frequently missed or delayed.