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1.
Mycoses ; 67(4): e13718, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38551112

RESUMEN

BACKGROUND: Dermatomycoses count to the most frequent dermatoses in Cambodia. OBJECTIVES: The aim of this survey was to investigate the occurrence of dermatophytes in this Southeast Asian country. METHODS: From June 2017 to July 2018, skin scrapings were taken from 67 patients with superficial dermatophytosis for mycological diagnostics. Identification of dermatophytes was confirmed by sequencing of the 'internal transcribed spacer'-(ITS) region of the rDNA, and the gene of the Translation Elongation Factor (TEF)-1α. RESULTS: Patients were suffering from tinea corporis and tinea inguinalis/cruris 42/67 (63%), tinea capitis/faciei 14/67 (21%), tinea corporis/capitis/faciei 6/67 (9%), tinea manuum/pedis 2/67 (3%), tinea pedis 2/67 (3%) and tinea manuum 1/67 (1%). Both, by culture and/or PCR, a dermatophyte was detected in 52 (78%) out of 67 samples. Culture positive were 42 (81%) of 52, PCR positive were 50 (96%). The following dermatophytes were found: Trichophyton (T.) rubrum, 36/52 strains (69%, 29 by culture), T. mentagrophytes/T. interdigitale (TM/TI) 9/52 (17%, six by culture) and Microsporum (M.) canis 5/52 strains (10%, by culture). One strain of Nannizzia (N.) incurvata 1/52 (2%) and N. nana 1/52 (2%) was isolated. Based on sequencing, we demonstrated that two T. mentagrophytes strains out of the nine TM/TI represented the new ITS genotype XXV Cambodia. We found one T. mentagrophytes strain genotype VIII (now, reclassified as T. indotineae). This isolate was terbinafine resistant, and it exhibited the amino acid substitution Phe397Leu in the squalene epoxidase. Three strains of T. interdigitale genotype II* were isolated. CONCLUSION: This is the first survey on epidemiology of dermatophytes in Cambodia. Currently, T. rubrum represents the most frequent species in Cambodia. One Indian strain genotype VIII T. mentagrophytes was found. A highlight was the first description of the new T. mentagrophytes genotype XXV Cambodia.


Asunto(s)
Arthrodermataceae , Dermatomicosis , Dermatosis de la Mano , Tiña , Humanos , Cambodia/epidemiología , Tiña/epidemiología , Trichophyton , Tiña del Pie/epidemiología , Dermatomicosis/epidemiología
2.
J Dtsch Dermatol Ges ; 21(6): 678-692, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37212291

RESUMEN

Onychomycosis is a fungal infection of the fingernails and toenails. In Europe, tinea unguium is mainly caused by dermatophytes. The diagnostic workup comprises microscopic examination, culture and/or molecular testing (nail scrapings). Local treatment with antifungal nail polish is recommended for mild or moderate nail infections. In case of moderate to severe onychomycosis, oral treatment is recommended (in the absence of contraindications). Treatment should consist of topical and systemic agents. The aim of this update of the German S1 guideline is to simplify the selection and implementation of appropriate diagnostics and treatment. The guideline was based on current international guidelines and the results of a literature review conducted by the experts of the guideline committee. This multidisciplinary committee consisted of representatives from the German Society of Dermatology (DDG), the German-Speaking Mycological Society (DMykG), the Association of German Dermatologists (BVDD), the German Society for Hygiene and Microbiology (DGHM), the German Society of Pediatric and Adolescent Medicine (DGKJ), the Working Group for Pediatric Dermatology (APD) and the German Society for Pediatric Infectious Diseases (DGPI). The Division of Evidence-based Medicine (dEBM) provided methodological assistance. The guideline was approved by the participating medical societies following a comprehensive internal and external review.


Asunto(s)
Onicomicosis , Adolescente , Humanos , Niño , Onicomicosis/diagnóstico , Onicomicosis/tratamiento farmacológico , Antifúngicos/uso terapéutico , Uñas , Administración Oral , Europa (Continente)
3.
Hautarzt ; 72(10): 878-891, 2021 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-33835190

RESUMEN

Trichophyton (T.) tonsurans is considered as the main causative agent of tinea gladiatorum (ringworm) in contact and martial arts worldwide and regularly leads to outbreaks. In the national wrestling squad in Leipzig, dermatophytoses occurred frequently and recurrently in children and adolescents for over a 2-year period. The wrestlers came to the dermatologist's office for clinical examination and sampling. Dermal scales and hair roots as well as smears were examined mycologically with fluorescence optical preparation, fungal culture, and polymerase chain reaction (PCR) for dermatophyte DNA. Sequencing of the dermatophyte rDNA served as culture confirmation test. Environmental investigations in the wrestler training center included contact cultures and smears from surfaces, in particular from the mats. T. tonsurans was culturally and/or with PCR detectable in 21 out of 25 children and adolescents plus one trainer. T. tonsurans grew in one of ten contact cultures of mats and floors in the wrestling training center, and T. interdigitale was found in another culture. Smears from the mats resulted in a culture of T. tonsurans detection twice. The PCR was positive for T. tonsurans three times. Within 14 days, T. tonsurans developed small, flat, radiating, granular and white-colored colonies with a mahogany-brown reverse side on the fungal culture media. The sequencing of the internal transcribed spacer (ITS) region of the rDNA and the translation elongation factor 1 α (TEF 1 α) gene confirmed the species T. tonsurans in all cases. T. interdigitale that was found from a mat was also identified by sequencing. Eight T. tonsurans strains were subjected to in vitro susceptibility testing to terbinafine. All isolates were sensitive to terbinafine in vitro with minimal inhibitory concentrations of ≤ 0.1 µg/ml.


Asunto(s)
Trichophyton , Lucha , Adolescente , Arthrodermataceae , Niño , Brotes de Enfermedades , Humanos , Terbinafina
4.
Mycoses ; 63(7): 717-728, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32301159

RESUMEN

BACKGROUND: An alarming increase in recalcitrant dermatophytosis has been witnessed in India over the past decade. Drug resistance may play a major role in this scenario. OBJECTIVES: The aim of the present study was to determine the prevalence of in vitro resistance to terbinafine, itraconazole and voriconazole in dermatophytes, and to identify underlying mutations in the fungal squalene epoxidase (SQLE) gene. PATIENTS/METHODS: We analysed skin samples from 402 patients originating from eight locations in India. Fungi were identified by microbiological and molecular methods, tested for antifungal susceptibility (terbinafine, itraconazole, voriconazole), and investigated for missense mutations in SQLE. RESULTS: Trichophyton (T.) mentagrophytes internal transcribed spacer (ITS) Type VIII was found in 314 (78%) samples. Eighteen (5%) samples harboured species identified up to the T interdigitale/mentagrophytes complex, and T rubrum was detected in 19 (5%) samples. 71% of isolates were resistant to terbinafine. The amino acid substitution Phe397Leu in the squalene epoxidase of resistant T mentagrophytes was highly prevalent (91%). Two novel substitutions in resistant Trichophyton strains, Ser395Pro and Ser443Pro, were discovered. The substitution Ala448Thr was found in terbinafine-sensitive and terbinafine-resistant isolates but was associated with increased MICs of itraconazole and voriconazole. CONCLUSIONS: The high frequencies of terbinafine resistance in dermatophytes are worrisome and demand monitoring and further research. Squalene epoxidase substitutions between Leu393 and Ser443 could serve as markers of resistance in the future.


Asunto(s)
Antifúngicos/uso terapéutico , Arthrodermataceae/efectos de los fármacos , Farmacorresistencia Fúngica Múltiple/genética , Proteínas Fúngicas/genética , Adolescente , Adulto , Anciano , Arthrodermataceae/clasificación , Arthrodermataceae/enzimología , Niño , Femenino , Humanos , India , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mutación Missense , Escualeno-Monooxigenasa/genética , Adulto Joven
5.
Hautarzt ; 71(9): 705-710, 2020 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-32394081

RESUMEN

Three boys from the same city, treated by the same dermatologist, developed tinea capitis. Two of them, 4 and 8 years old, underwent mycological diagnostic workup. However, no pathogens familiar in this country, such as Microsporum (M.) canis or Trichophyton (T.) tonsurans, were isolated, but instead that of a dermatophyte that has not been found in Germany for decades. Both dermatophyte isolates showed white-beige-brownish colonies with a flat, radiating edge and a central, verrucous curvature. The sequencing of the internal transcribed spacer (ITS) region of the rDNA confirmed the suspicion of M. ferrugineum already expressed based on the morphological picture. The anthropophilic dermatophyte occurs in the Middle East, Asia, Eastern Europe and Africa and is considered to be the cause of tinea capitis or tinea corporis in children and adolescents. In 2016, M. ferrugineum has again been isolated in Germany, probably as a result of migration movements. The fungus is strikingly isolated to martial arts, especially wrestlers. It mainly affects children and adolescents, some with a Russian-German background. The anthropophilic dermatophyte is transmitted directly from person to person, especially in the case of tinea capitis. An indirect transmission, for example, via mats in martial arts is likely.


Asunto(s)
Microsporum/aislamiento & purificación , Tiña del Cuero Cabelludo/diagnóstico , Antifúngicos/uso terapéutico , Arthrodermataceae , Niño , Preescolar , Alemania , Humanos , Masculino , Microsporum/clasificación , Tiña del Cuero Cabelludo/tratamiento farmacológico , Resultado del Tratamiento
6.
Mycoses ; 62(4): 336-356, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30561859

RESUMEN

The disease burden of chronic-relapsing and therapy-refractory superficial dermatophytosis dramatically increased in India within the past 5-6 years. In order to evaluate the prevalence of this trend, 201 skin scrapings were collected from patients from all parts of India and were tested for dermatophytes using both fungal culture and a PCR-ELISA directly performed with native skin scrapings. Fungal culture material was identified by genomic Sanger sequencing of the internal transcribed spacer (ITS) region and the translation elongation factor (TEF)-1α gene. In total, 149 (74.13%) out of the 201 samples showed a dermatophyte-positive culture result. Out of this, 138 (92.62%) samples were identified as Trichophyton (T.) mentagrophytes and 11 (7.38%) as Trichophyton rubrum. The PCR-ELISA revealed similar results: 162 out of 201 (80.56%) samples were dermatophyte-positive showing 151 (93.21%) T mentagrophytes- and 11 (6.79%) T rubrum-positive samples. In this study, we show for the first time a dramatic Indian-wide switch from T rubrum to T mentagrophytes. Additionally, sequencing revealed a solely occurring T mentagrophytes "Indian ITS genotype" that might be disseminated Indian-wide due to the widespread abuse of topical clobetasol and other steroid molecules mixed with antifungal and antibacterial agents.


Asunto(s)
Epidemias , Tiña/epidemiología , Trichophyton/clasificación , Trichophyton/aislamiento & purificación , Adolescente , Adulto , Anciano , Niño , Preescolar , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Factor 1 de Elongación Peptídica/genética , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Trichophyton/genética , Adulto Joven
7.
Hautarzt ; 70(11): 888-896, 2019 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-31098692

RESUMEN

A 6 month-old-female infant from Bahrain visiting Germany with her family for a holiday was seen by us for extensive dermatophytosis of the back, buttocks, chest and groins. Topical treatment by terbinafine for over 2 months was not successful. Other family members including adults and children were treated in Bahrain with topical antifungals and oral voriconazole which was not helpful. Mycological examination performed in Germany revealed the detection of the zoophilic dermatophyte Trichophyton (T.) mentagrophytes. The newly described genotype VIII within the species T. mentagrophytes was identified by sequencing of the "internal transcribed spacer" (ITS) region of the fungal rDNA. This genotype of T. mentagrophytes is the main causative agent of the current epidemic of chronic recalcitrant dermatophytoses in India. Transmission of this Indian genotype of T. mentagrophytes to other countries due to globalization is a serious issue to be considered. Moreover, a significant percentage of these Indian T. mentagrophytes strains are resistant to terbinafine both in vitro and by the way of genetic point mutations in the squalene epoxidase (SQLE) gene. Some are also found to be partially resistant against itraconazole and voriconazole. The point mutation TTC/TTA was found by SQLE mutation analysis in this particular T. mentagrophyte isolate from Bahrain. This point mutation is closely associated with F397L amino acid substitution of the enzyme indicative of in vitro resistance of the dermatophyte against terbinafine. The girl was successfully treated by topical miconazole and later by ciclopirox olamine. This is the first report on an infection due to a terbinafine-resistant T. mentagrophytes strain of the ITS genotype VIII from India in Germany.


Asunto(s)
Antifúngicos/farmacología , Ciclopirox/uso terapéutico , Miconazol/uso terapéutico , Terbinafina/farmacología , Tiña del Cuero Cabelludo/tratamiento farmacológico , Tiña/tratamiento farmacológico , Trichophyton/genética , Trichophyton/aislamiento & purificación , Adulto , Antifúngicos/uso terapéutico , Bahrein , Femenino , Genotipo , Alemania , Humanos , Lactante , ARN de Hongos , Análisis de Secuencia de ARN , Terbinafina/uso terapéutico , Tiña/diagnóstico , Tiña del Cuero Cabelludo/diagnóstico , Trichophyton/clasificación
8.
Mycoses ; 61(3): 152-158, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29082569

RESUMEN

Deep trichophytosis is relatively uncommon. The infection of the bearded area is also known as sycosis barbae or tinea barbae and can be caused by various fungal species, most often zoophilic fungi. We report on an 80-year-old male patient with severe sycosis barbae who had no animal contact and was treated with systemic antibiosis without improvement. Microbial and mycological investigations using swabs from oozing lesions revealed Staphylococcus haemolyticus and Candida parapsilosis. Histology demonstrated fungal elements in hair follicles. Paraffin-embedded material was subjected to further mycological analysis. For molecular diagnostics DNA was prepared from paraffin sections for real-time polymerase chain reaction (RT-PCR). For sequencing, DNA was isolated from paraffin-embedded skin tissue and the ITS region of the rDNA was selected. Sequencing of the ITS2 region of rRNA revealed a 100% accordance with Trichophyton (T.) verrucosum. Treatment with oral terbinafine achieved a complete remission. Sycosis barbae is an important differential diagnosis for infections of the bearded area. Nucleic acid amplification techniques (NAAT) are more and more used for direct examination of dermatophytes in clinical samples, eg T. verrucosum. NAAT are also used as culture confirmation tests for identification of rare dermatophytes like T. verrucosum. Today, singleplex and multiplex quantitative real-time PCR (qRT-PCR) assays for the detection of the most common dermatophytes including T. verrucosum in clinical specimens are available. Recently, an ITS2 PCR assay has been successfully used for direct detection of T. verrucosum in paraffin-embedded formalin-fixed skin tissue. The PCR is fast and highly specific. The sensitivity of direct molecular detection of the dermatophytes both in native clinical material, and in paraffin-embedded skin tissue can been increased.


Asunto(s)
Cara/microbiología , Foliculitis/microbiología , Tiña/microbiología , Trichophyton/aislamiento & purificación , Anciano de 80 o más Años , Antifúngicos/uso terapéutico , Candida parapsilosis/genética , Candida parapsilosis/aislamiento & purificación , ADN de Hongos/genética , ADN Ribosómico/análisis , Cara/fisiopatología , Foliculitis/diagnóstico , Foliculitis/tratamiento farmacológico , Folículo Piloso/microbiología , Humanos , Masculino , Naftalenos/uso terapéutico , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Piel/microbiología , Piel/patología , Terbinafina , Tiña/diagnóstico , Tiña/tratamiento farmacológico , Resultado del Tratamiento , Trichophyton/efectos de los fármacos , Trichophyton/genética
10.
Mycopathologia ; 183(2): 391-398, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29067631

RESUMEN

Nannizzia praecox, formerly known as Microsporum praecox, is a geophilic dermatophyte. Up to now 31 cases of human tinea have been reported in the literature, most of them with an inflammatory course. Three recent cases diagnosed in Germany within 1 year suggest that the fungus might be a more common cause of human dermatophytosis than reported so far. This might be based on the fact that N. praecox is often found in an equine environment and that horse riding is becoming more popular recently.


Asunto(s)
Arthrodermataceae/aislamiento & purificación , Tiña/diagnóstico , Tiña/patología , Arthrodermataceae/clasificación , Arthrodermataceae/citología , Arthrodermataceae/genética , Análisis por Conglomerados , Técnicas Citológicas , Alemania/epidemiología , Humanos , Técnicas Microbiológicas , Microscopía , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia , Tiña/microbiología
11.
J Dtsch Dermatol Ges ; 16(1): 21-32, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29314679

RESUMEN

BACKGROUND: Formerly only referred to as a subspecies (T. mentagrophytes var. quinckeanum), T. quinckeanum once again constitutes a distinct species according to the updated taxonomy of dermatophytes. PATIENTS AND METHODS: During routine diagnostic tests conducted at the Mycology Laboratory, Mölbis, Germany, between 11/2013 to 1/2017 (three years and three months), all specimens sent in were examined for T. quinckeanum. Molecular biology methods employed included: 1) DNA hybridization (PCR ELISA), 2) gene sequencing of the ITS region and TEF-1α, and 3) in some cases, MALDI-TOF mass spectrometry. RESULTS: Overall, 62 strains of T. quinckeanum were found. Sixty-eight percent of patients were female; 43 % were children and adolescents (≤ 19 years of age). Cats were a frequent source of infection. Sequencing of all 62 strains revealed a concordance of 100 % with T. quinckeanum sequences contained in the NCBI database. Isolates analyzed by MALDI-TOF mass spectrometry showed specific spectra. CONCLUSIONS: In Germany, the zoophilic dermatophyte T. quinckeanum currently appears to be more prevalent than expected. T. quinckeanum strains were isolated from children and adults with dermatomycosis and tinea capitis. Sources of infection with T. quinckeanum include small rodents (mice), horses, and - remarkably commonly -  cats. Given that unequivocal morphological identification of this dermatophyte is not always possible, molecular methods have to be employed in the diagnosis.


Asunto(s)
Dermatomicosis/diagnóstico , Epidemiología Molecular , Tiña/diagnóstico , Trichophyton/genética , Zoonosis/diagnóstico , Adolescente , Adulto , Animales , Técnicas Bacteriológicas , Gatos/microbiología , Niño , Estudios Transversales , Dermatomicosis/epidemiología , Dermatomicosis/transmisión , Femenino , Humanos , Masculino , Factor 1 de Elongación Peptídica/genética , Análisis de Secuencia de ADN , Tiña/epidemiología , Tiña/transmisión , Diente no Vital , Trichophyton/clasificación , Trichophyton/patogenicidad , Adulto Joven , Zoonosis/transmisión
15.
J Dtsch Dermatol Ges ; 13(5): 387-410; quiz 411, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25918080

RESUMEN

Treatment of dermatophyte infections is based on the clinical picture and mycological detection of the causative pathogen. Based on the appropriate indication, onychomycosis can be treated topically using an antimycotic nail lacquer. Atraumatic nail abrasion with 40 % urea ointment has a beneficial effect on healing. Continuous treatment of onychomycosis with terbinafine represents the most effective systemic therapy. Terbinafine or itraconazole are the safest and most effective antimycotic agents for the treatment of onychomycosis in children. For laser therapy of onychomycosis, only a few studies on clinical efficacy are available. Regarding tinea capitis, targeted species-specific therapy of dermatophytosis of the scalp is currently recommended. Terbinafine, yet also itraconazole and fluconazole, are effective in tinea capitis caused by Trichophyton species. Microsporum infections of the scalp are preferably treated with griseofulvin, alternatively with itraconazole or fluconazole. Terbinafine is less effective. Candidal intertrigo are topically treated with nystatin, but azoles or ciclopirox olamine are also suitable candidates. Systemically, fluconazole or itraconazole are used. Topical and systemic antimycotics are equivalent forms of therapy in acute vulvovaginal mycosis. Fluconazole is the drug of choice in chronic recurrent vulvovaginal mycosis caused by Candida albicans. Ketoconazole shows very good efficacy in tinea versicolor. With respect to systemic treatment of severe and widespread tinea versicolor, itraconazole is the drug of choice.


Asunto(s)
Antiinflamatorios/administración & dosificación , Antifúngicos/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Dermatomicosis/diagnóstico , Dermatomicosis/tratamiento farmacológico , Monitoreo de Drogas/métodos , Administración Cutánea , Relación Dosis-Respuesta a Droga , Humanos , Inyecciones Intravenosas , Resultado del Tratamiento
16.
J Dtsch Dermatol Ges ; 12(3): 188-209; quiz 210, 188-211; quiz 212, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24533779

RESUMEN

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.


Asunto(s)
Arthrodermataceae/aislamiento & purificación , Dermatomicosis/epidemiología , Dermatomicosis/microbiología , Diabetes Mellitus/epidemiología , Enfermedades del Sistema Inmune/epidemiología , Insuficiencia Venosa/epidemiología , Causalidad , Comorbilidad , Dermatomicosis/genética , Diabetes Mellitus/genética , Diabetes Mellitus/microbiología , Medicina Basada en la Evidencia , Predisposición Genética a la Enfermedad/genética , Humanos , Enfermedades del Sistema Inmune/genética , Enfermedades del Sistema Inmune/microbiología , Prevalencia , Factores de Riesgo , Tasa de Supervivencia , Insuficiencia Venosa/genética , Insuficiencia Venosa/microbiología
17.
J Dtsch Dermatol Ges ; 12(9): 749-77, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25176455

RESUMEN

Most fungal infections of the skin are caused by dermatophytes, both in Germany and globally. Tinea pedis is the most frequent fungal infection in Western industrial countries. Tinea pedis frequently leads to tinea unguium, while in the elderly, both may then spread causing tinea corporis. A variety of body sites may be affected, including tinea glutealis, tinea faciei and tinea capitis. The latter rarely occurs in adults, but is the most frequent fungal infection in childhood. Following antifungal treatment of tinea unguium and also tinea capitis a dermatophytid or hyperergic reaction to dermatophyte antigens may occur. Yeast infections affect the mucous membranes both of the gastro-intestinal system and the genital tract as candidiasis mostly due to Candida albicans. Cutaneous candidiasis affects predominantely the intertriginous regions such as groins and the inframammary area, but also the intertriginous space of fingers and toes. In contrast, pityriasis versicolor is a superficial epidermal fungal infection primarily on the the trunk. Mold infections are rare in dermatology; they play a role nearly exclusively in nondermatophyte-mold (NDM) onychomycosis. The diagnosis of dermatomycoses comprises the microscopic detection of fungi using the potassium hydroxide preparation or alternatively the fluorescence optical Blankophor preparation together with culture. The histological fungal detection with PAS staining possesses a high sensitivity, and it should play a more important role in particular for diagnosis of onychomycosis. Molecular biological methods, based on the amplification of fungal DNA with use of specific primers for the distinct causative agents are on the rise. With PCR, such as dermatophyte-PCR-ELISA, fungi can be detected directly in clinical material in a highly specific and sensitive manner without prior culture. Today, molecular methods, such as Matrix Assisted Laser Desorption/Ionization Time-Of-Flight Mass Spectrometry (MALDI TOF MS) as culture confirmation assay, complete the conventional mycological diagnostics.


Asunto(s)
Dermatomicosis/diagnóstico , Dermatomicosis/microbiología , Dermoscopía/métodos , Hongos/aislamiento & purificación , Técnicas de Diagnóstico Molecular/métodos , Hongos/clasificación , Humanos
18.
J Dtsch Dermatol Ges ; 12(7): 571-81, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24981469

RESUMEN

In Germany, infections due to the zoophilic dermatophyte Trichophyton (T.) species of Arthroderma benhamiae are being more frequently diagnosed. The source of infection of this emerging pathogen overlaps with that of the zoophilic species T. interdigitale. The most common source are guinea pigs. T. species of Arthroderma benhamiae causes inflammatory dermatophytosis in children and adolescents. In addition to tinea capitis, it may cause both tinea corporis, tinea manus and frequently tinea faciei. In Germany, T. species of Arthroderma benhamiae is a frequent zoophilic dermatophyte, which in regions is probably more frequent than Microsporum canis. The mycological identification of the isolates with their yellow stained colonies is based on their macroscopic and microscopic features. However, some exhibit colony features consistent with those of T. interdigitale. These strains only can be identified unambiguously by means of molecular techniques. Using detection methods such as PCR-ELISA or real-time PCR, the dermatophyte can be identified directly from clinical material. Sequencing of the internal transcribed spacer region (ITS) of the ribosomal DNA has been approved as culture confirmation test for T. species of Arthroderma benhamiae. In addition, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) is useful. Widespread dermatophytosis due to T. species of Arthroderma benhamiae, in particular of tinea capitis, requires oral antifungal agents. Terbinafine is most effective, alternatives are fluconazole and itraconazole.


Asunto(s)
Antifúngicos/uso terapéutico , Dermatomicosis/diagnóstico , Dermatomicosis/tratamiento farmacológico , Cobayas/microbiología , Tiña/diagnóstico , Tiña/tratamiento farmacológico , Trichophyton , Animales , Dermatomicosis/microbiología , Humanos , Tiña/microbiología
19.
Dermatologie (Heidelb) ; 75(2): 134-146, 2024 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-38066287

RESUMEN

Onychomycosis is a common infectious nail disease occurring worldwide. The mycological diagnosis of onychomycosis is primarily used for differential diagnostic differentiation from other, mostly inflammatory nail diseases, such as nail psoriasis or onychodystrophies of other causes. Conventional laboratory diagnostics when onychomycosis is suspected is based on microscopic detection of fungi in the nail material using fluorescence-optical potassium hydroxide preparations and culture of the pathogen. Molecular amplification methods allow a more sensitive and specific identification of the causative dermatophyte. Here, in 108 patients with onychomycosis, the dermatophytes were identified by culture and/or molecular biology using polymerase chain reaction (PCR) and the species identification was confirmed with subsequent sequencing. The dermatophytes were analyzed based on macromorphological and microscopic features. A dermatophyte was cultured in 56 of the 108 patients. Among them were 31 isolates of Trichophyton (T.) rubrum and 25 of T. interdigitale. All species identifications were subsequently confirmed by rDNA sequencing with concordant results in 54 of 56 patients. Two primarily as T. interdigitale identified specimens were revealed to be T. quinckeanum and T. tonsurans by molecular methods. T. quinckeanum, which is a zoophilic dermatophyte and a so-called emerging pathogen in dermatomycology, was isolated here for the first time as the causative agent of onychomycosis. The other dermatophyte, initially thought to be T. interdigitale, turned out to be T. tonsurans on molecular biology. This anthropophilic dermatophyte is also a rarity in onychomycosis. In addition, T. rubrum was identified by PCR in 34 of the 52 nail specimens that did not grow culture, and T. interdigitale in 18 nail specimens. However, the morphological identification of the four different dermatophytes species proved problematic. Neither the colony morphology nor the microscopic features of the dermatophytes allow clear differentiation of the pathogens. Microconidia, macroconidia, chlamydospores, and arthrospores are inconsistent in occurrence, number, microscopic distribution, and shape. The urease activity also did not allow an assignment of the dermatophyte species. These results indicate that the most sensitive detection and reliable identification of causative dermatophytes in onychomycosis is only possible by molecular methods.


Asunto(s)
Arthrodermataceae , Enfermedades de la Uña , Onicomicosis , Humanos , Onicomicosis/diagnóstico , Arthrodermataceae/genética , Patología Molecular
20.
Dermatologie (Heidelb) ; 75(3): 238-252, 2024 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-38095686

RESUMEN

Dermatophyte identification using traditional methods such as optics-based direct fluorescence microscopy and culture is nowadays supplemented by molecular biological methods. The validity of dermatophyte DNA detection with direct uniplex-polymerase chain reaction-enzyme immunoassay (PCR-EIA) in nail samples was proven by sequence analysis of the ribosomal internal transcribed spacer (ITS) region. A total of 108 dermatophytes, isolated from patients with onychomycosis, were positive for Trichophyton rubrum (TR) and Trichophyton interdigitale (TI) in culture and/or uniplex-PCR-EIA. Conventional methods for dermatophyte identification were complemented by direct uniplex-PCR-EIA and sequence analysis of the ribosomal ITS region (18S rRNA, ITS1, 5.8S rRNA, ITS2, 28S rRNA). Of 108 patients (average age 62, median age 73), 56 showed cultural growth with 31 of them being identified as TR and 23 as TI. There was high agreement with the sequence analysis. Surprisingly, the pathogen of a single nail sample was identified as T. quinckeanum (formerly T. mentagrophytes sensu stricto), a rare zoophilic dermatophyte in Germany. A single TI strain turned out to be a misidentified T. tonsurans based on the sequence analysis. In all, 34 of the 52 specimens lacking cultural growth were detected by PCR as TR, and 18 specimens could be identified as TI. The results of dermatophyte identification of culture-negative nail samples were also in agreement with the results of sequence analysis. Molecular biological methods are well applicable, and they show high reliability for direct dermatophyte identification in nail samples without prior cultivation. Especially for nail samples without cultural growth, PCR-based dermatophyte identification was highly specific and sensitive.


Asunto(s)
Arthrodermataceae , Onicomicosis , Humanos , Persona de Mediana Edad , Anciano , Onicomicosis/diagnóstico , Arthrodermataceae/genética , Trichophyton/genética , ADN Ribosómico , Patología Molecular , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa/métodos , ADN de Hongos/genética , Microscopía Fluorescente , Análisis de Secuencia
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