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Background: The T indotineae population shows a high amount of terbinafine resistant isolates based on different point mutations of squalene epoxidase erg1 (ergosterol) gene. A significant proportion of these isolates also show azole resistance., Objectives: Elucidation of the molecular mechanism for azole resistance, especially the identification of mutations in the sterol 14-α demethylase Erg11 genes, which encode for enzymes interacting with azoles., Methods: Sequencing of putative Erg11 genes and analysis of phenotypic resistance pattern using a microplate-laser-nephelometry-based growth assay., Results: Four different types of Erg11B mutants were detected; two double mutants with Ala230Thr/Asp441Gly, respectively, Ala230/Tyr444His and single mutants with Gly443Glu, Tyr444Cys and Tyr444His. All isolates featured the wild type genotype of Erg11A. All strains demonstrated different combinations of Erg1 and Erg11 genotypes., Conclusion: Resistance against terbinafine and azoles developed several times independently within the T indotineae population. The challenge for fungal treatment is, therefore, that species identification is not enough for prediction of therapeutic efficacy of antifungals. In the future, it will also become important to analyse genes involved in resistance mechanisms., (© 2021 The Authors. Mycoses published by Wiley-VCH GmbH.)

Background: The Indian ITS genotype VIII Trichophyton mentagrophytes population shows a high amount of different erg1 (ergosterol) mutants encoding for squalene epoxidase, which catalyses the first step of ergosterol biosynthesis., Objectives: Illumination of the implication of point mutations at position Ala448Thr in single and double erg1 T mentagrophytes mutants because mutants of this type were abundantly found within the Indian fungal population., Methods: Growth in fluconazole or terbinafine containing medium was analysed using a microplate-laser-nephelometry (MLN)-based growth assay., Results: Ala 448 Thr erg1 single mutants were terbinafine sensitive, but about 50% of isolates showed an increased fluconazole resistance, whereas 95% of the double mutants (Phe 397 Leu, Ala 448Thr) demonstrated combined terbinafine and increased fluconazole resistance., Conclusion: The new Indian T mentagrophytes populations show several point mutations in erg1. Point mutations at position 397 were previously described and cause terbinafine resistance. A large part of the double mutants exhibit resistance to terbinafine and fluconazole, demonstrating a selective advantage of the combination of both mutations., (© 2020 The Authors. Mycoses published by Blackwell Verlag GmbH.)

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., (© 2020 The Authors. Mycoses published by Blackwell Verlag GmbH.)

Background: Superficial fungal infections are often seen in day-to-day clinical practice, and their prevalence continues to rise worldwide. Over the years, a change in the pattern of dermatophytoses has been noted., Objectives: This study aimed to determine the epidemiologic profile of dermatophytes at the Department of Dermatology, University Hospital Jena, from 2007 to 2013., Methods: The retrospective study was carried out with a total of 4556 samples collected from 3607 patients suspected of superficial fungal infections during the 7-year study period., Results: Among the 3607 suspected patients, 1951 (54.09%) were men and 1656 (45.91%) were women. Of 4556 samples, 703 (15.43%) samples were positive for fungal culture, which included 585 (83.21%) dermatophytes and 118 (16.79%) non-dermatophytes. Trichophyton (T.) rubrum was the most common isolated pathogen in 73.33% of the dermatophyte cases. Among dermatophyte-infected patients, men were most likely to be affected (63.48%) as well as those of higher age (61 to 80). The most commonly affected areas were nails (33.16%) and feet (33%). T rubrum was recurrently isolated in several regions with exception of the scalp where M canis (58.33%) was the most frequently isolated pathogen. About 16.04% of cases had a history of treatment taken prior to sampling. The majority of the affected individuals did not have any prior animal contact (77.26%). T benhamiae was exclusively associated with contact to guinea pigs., Conclusion: Trichophyton rubrum was the most frequently isolated pathogen in several regions except the scalp. New dermatophyte species emerged with time especially T benhamiae., (© 2020 The Authors. Mycoses published by Blackwell Verlag GmbH.)

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., (© 2018 Blackwell Verlag GmbH.)

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., (© 2017 Blackwell Verlag GmbH.)

Species identification of yeasts is based on biochemical (e.g. API ID 32 C®, bioMérieux) and molecular biological approaches. As an alternative to DNA-dependent methods, mass spectral analysis based identification of micro-organisms has become increasingly recognized. In a number of studies, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been applied for the rapid classification and identification of micro-organisms. In this study, the applicability of MALDI-TOF MS for identifying yeasts isolated from dermatological patients was analysed and compared with the results from the API ID 32 C® system. Furthermore, sequencing the internal transcribed spacer (ITS) regions of the ribosomal DNA was employed as reference method. Candida (C.) albicans was isolated in 41.9% of all cases, C. parapsilosis in 20.3%, C. glabrata in 10.8%, and C. krusei in 6, 8.1%. Rarely isolated yeasts were Candida colliculosa, famata, guilliermondii, lusitaniae, and tropicalis as well as Geotrichum candidum, Rhodotorula mucilaginosa and Trichosporon mucoides. The MALDI TOF results were equal to the results gained by ITS sequence analysis in 94%, whereas API ID 32 C® provided the correct diagnosis in 84.3% (of all cases). This lower identification rate is mostly referable to frequent misidentifications of C. krusei as C. inconspicua/norvegensis,Candida tropicalis, or Geotrichum capitatum. In contrast, all C. krusei strains were correctly identified by MALDI TOF MS. In conclusion, species identification by MALDI-TOF MS was proven to be consistent with ITS sequence analysis; the technique has a resolving power comparatively as high as ITS sequence analysis., (© 2011 Blackwell Verlag GmbH.)

Tinea corporis classically presents as an erythematous annular plaque with a scaly, centrifugally advancing border. However, sometimes vesicles and pustules are observed. Occasionally, even frank bullae appear secondary to severe inflammation. Diagnostic difficulties arise when atypical manifestations mimic other inflammatory skin diseases, including atopic or seborrheic dermatitis, subacute cutaneous lupus erythematosus, or vesicular diseases. We report five cases of atypical tinea corporis, where the initial clinical diagnosis was different from dermatophytosis. The differential diagnoses and the diagnostic difficulties related to atypical manifestations of fungal infections are discussed. Moreover, our cases emphasise the importance of conventional histological examination, which enables a fast, correct diagnosis.

From the epidemiological point of view, Trichophyton rubrum is the most important dermatophyte in the Western world. Mostly, the lesions of fungal infections of the skin are restricted and circumscribed. Immunodeficiency, diabetes or treatment with steroids, however, favour widespread disease involving the entire integument. In the present study, we describe a patient without immunodeficiency or diabetes presenting with widespread tinea corporis caused by T. rubrum. The fungal isolate showed atypical morphological features. Moreover, the typical metabolic features (negative urease test, production of red pigment on potato dextrose agar) were expressed with delay after 6 weeks of cultivation. Thus, sequencing of the internal transcribed spacer of the ribosomal DNA was applied to identify the fungal isolate and led us to the correct diagnosis, before conventional mycological methods were successful.

Anaphylactic reactions to food containing allergens in the consumption or preparation of food are well known. However, allergy in the preparation of sausages has rarely been described. In the present study a 26-year-old-butcher was investigated who had a severe anaphylactic reaction developing sneezing, rhinitis, conjunctivitis, generalised pruritus, followed by widespread urticaria, Quincke's oedema and dyspnoe after starting to prepare sausages containing red yield rice. Red yield rice is produced by the fungus Monascus purpureus. It was the first time that Monascus purpureus could be shown as allergic agent by means of prick-to-prick test, Cellular Antigen Stimulation Test (CAST) and different immunoblots.