agar and Tinea

Using a newly-developed medium, i.e., combined deactivators-supplemented agar medium (CDSAM), the viability of dermatophytes in skin scales was evaluated. Culture studies were conducted with skin scales collected from 44 patients with tinea pedis who had been treated for two weeks with topical antifungal drugs. Sixty-four percent of the specimens were mycologically positive on CDSAM, while only 23% of these same specimens were positive when cultured on conventional Sabouraud's dextrose agar medium (SDA). Alternatively, 36% of all cases were negative on both media. The experimental data from this clinical study indicate that CDSAM was more useful than SDA in accurately evaluating the efficacy of antifungal drugs since the former minimized the residual effects of drug residues remaining in the skin samples.

Topics: Administration, Topical; Agar; Antifungal Agents; Chloramphenicol; Culture Media; Cycloheximide; Humans; Microbiological Techniques; Phosphatidylcholines; Polysorbates; Sensitivity and Specificity; Sisomicin; Tinea; Treatment Outcome; Trichophyton

Fungal infections are the most frequent dermatoses. The gold standard treatment for dermatophytosis is the squalene epoxidase (SQLE) inhibitor terbinafine. Pathogenic dermatophytes resistant to terbinafine are an emerging global threat. Here, we determine the proportion of resistant fungal skin infections, analyse the molecular mechanisms of terbinafine resistance, and validate a method for its reliable rapid identification.. Between 2013 and 2021, we screened 5634 consecutively isolated Trichophyton for antifungal resistance determined by hyphal growth on Sabouraud dextrose agar medium containing 0.2 μg/mL terbinafine. All Trichophyton isolates with preserved growth capacity in the presence of terbinafine underwent SQLE sequencing. Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method.. Based on our data, we propose MIC of 0.015 μg/mL as a minimum breakpoint for predicting clinically relevant terbinafine treatment failure to standard oral dosing for dermatophyte infections. We further propose growth on Sabouraud dextrose agar medium containing 0.2 μg/mL terbinafine and SQLE sequencing as fungal sporulation-independent methods for rapid and reliable detection of terbinafine resistance.

Topics: Agar; Antifungal Agents; Arthrodermataceae; Glucose; Humans; Microbial Sensitivity Tests; Skin Diseases, Infectious; Squalene Monooxygenase; Terbinafine; Tinea; Trichophyton

Trichophyton rubrum and Trichophyton mentagrophytes spp. are two of the most frequently isolated dermatophytes causing dermatophytosis worldwide. Since the incidence of resistance to antifungal agents is increasing, antifungal susceptibility tests are needed to successfully treat dermatophytoses. Most of the methods currently available are complicated, time-consuming and lack of reference procedures. The aim of this work was to establish a simple protocol to test the susceptibility of dermatophytes isolated from clinical samples against five antifungal drugs using E-test and disk diffusion methods. We used the E-test on non-supplemented Mueller-Hinton agar plates to determine the minimum inhibitory concentrations (MICs) of fluconazole, itraconazole, voriconazole and amphotericin B, and disk diffusion method to determine the interpretive MIC of terbinafine. Fifty dermatophytes-10 T. rubrum and 40 T. mentagrophytes spp.-were assessed after only 96 h of colony growth. Terbinafine was the most active antifungal agent with an inhibition diameter greater than 70 mm (sensitivity > 20 mm), followed by voriconazole, itraconazole and amphotericin B with MICs ranging from 0.032 to 0.38 µg/mL, from 0.006 to 0.125 µg/mL and from 0.5 to 1.5 µg/mL, respectively. All isolates were resistant to fluconazole. Collectively, the less laborious E-test and disk diffusion method were shown to be suitable and reliable to determine antifungal sensitivity of dermatophytes. This simple standard protocol could be employed in the routine of clinical laboratories.

Topics: Agar; Antifungal Agents; Culture Media; Humans; Microbial Sensitivity Tests; Tinea; Trichophyton

Dermatophytosis is a fungal disease which ranked as one of the most common cutaneous condition in all over the world. The aim of this cross sectional observational study is to identify the etiological agent of dermatophytosis and comparison of Sabouraud dextrose agar (SDA) and Dermatophyte test medium (DTM) for the primary isolation of dermatophytes among the clinically suspected cases of dermatophytosis from the outpatient Department of Dermatology and Venereology, Mymensingh Medical College Hospital from July 2013 to December 2015. Two hundred thirty clinically suspected cases of dermatophytosis were subjected in this study. Sixty three cases (27.4%) were positive for fungus in direct microscopy while 53(23%) were culture positive. Trichophyton rubrum (83%) was found common etiological dermatophyte species followed by Trichophyton mentagrophytes 5(9.4%) and Epidermophyton floccosum 4(7.5%). There was no statistically significant difference between the SDA and DTM (p<0.01) in primary isolation of dermatophytes.

Topics: Agar; Arthrodermataceae; Cross-Sectional Studies; Glucose; Humans; Tinea; Trichophyton

The characteristics of macroconidia are the key to the identification of dermatophytic fungi. In this study, we compared Lowenstein-Jensen agar (LJA) with Borelli's lactritmel agar (BLA) for the ability to induce macroconidia production in a collection of Trichophyton mentagrophytes (12) and Trichophyton rubrum (12) complexes and in Arthroderma isolates (4). We evaluated 28 strains from across the world, which were mainly obtained from the culture collection of the Centraalbureau voor Schimmelcultures, Fungal Biodiversity Centre, The Netherlands. All cultures were incubated at 26 °C on the bench, and conidia formation was investigated every 5 days, over a period of 30 days after inoculation. At 15 days, strains grown on BLA demonstrated better macroconidia production than those grown on LJA, 23 (82.1%) versus 16 (57.1%) isolates, respectively. Thus, the use of BLA, an inexpensive medium that can be prepared in the laboratory, should facilitate conidiation and the presumptive identification of dermatophytic fungi in mycology and clinical microbiology laboratories.

Topics: Agar; Culture Media; Humans; Microbiological Techniques; Mycology; Spores, Fungal; Temperature; Time Factors; Tinea; Trichophyton

Allylamines are a newly developed group of drugs possessing a broad spectrum of activity against a wide range of fungi. With the advent of new antifungal drugs, susceptibility testing of fungi is receiving increased attention as important laboratory procedures for aiding in the selection of appropriate drug therapy.. In vitro susceptibility testing of 43 clinical isolates of dermatophytes which included Microsporum sp., (18) Trichophyton sp., (23) and Epidermophyton floccosum (2) were carried out against the two allylamine derivatives, naftifine and terbinafine, by agar dilution and disk diffusion methods.. Terbinafine was found to be more active minimal inhibitory concentration (MIC range < or = 0.0001-0.1 micrograms/mL), inhibiting 50% (MIC 50) and 90% (MIC 90) of the isolates at 0.01 and 0.1 micrograms/mL, respectively. The MIC 50s and MIC 90s of naftifine were 0.1 micrograms/mL (MIC range 0.001-0.5 micrograms/mL). Both the drugs showed good correlation between the MIC and sizes of zones of inhibition around the disks. Regression analysis was used to measure the degree of correlation between the MIC values and matched averaged zones of inhibition; the correlation coefficients for both terbinafine and naftifine were -0.6841 (P < 0.001) and -0.5455 (P < 0.001), respectively.. The allylamines, naftifine and terbinafine, could be used successfully for susceptibility testing of dermatophytes by the disk diffusion method. With proper standardization of the test conditions, in vitro susceptibility testing of filamentous fungi by disk diffusion would become a useful laboratory procedure in the near future for determining the best drug therapy.

Topics: Agar; Allylamine; Antifungal Agents; Diffusion; Drug Resistance, Microbial; Epidermophyton; Humans; Microbial Sensitivity Tests; Microsporum; Naphthalenes; Regression Analysis; Terbinafine; Tinea; Tinea Capitis; Trichophyton

Topics: Agar; Animals; Culture Media; Female; Guinea Pigs; Male; Skin; Spores, Fungal; Tinea; Trichophyton

Topics: Agar; Animals; Cattle; Cattle Diseases; Culture Media; Hair; Skin; Tinea; Trichophyton

Trichophyton rubrum strains freshly isolated from clinical material exhibited red pigment formation within 7 days at 26 degrees C on slant serum-albumin agar, initial pH 7.0. In Trichophyton mentagrophytes strains this phenomenon could not be observed. Since in the case of T. rubrum, yellow pigmentation will appear at an initial pH of 5.0, the use of initial pH values of 7.0 and 5.0 is recommended for diagnostic application of slant serum-albumin agar.

Topics: Agar; Diagnosis, Differential; Humans; Hydrogen-Ion Concentration; Pigments, Biological; Serum Albumin; Species Specificity; Tinea; Trichophyton

Topics: Agar; Ascomycota; Asparagine; Conjugation, Genetic; Culture Media; Hair; Humans; Keratins; Phenylalanine; Pigments, Biological; Quinic Acid; Shikimic Acid; Stereoisomerism; Tinea; Trichophyton; Tyrosine; Urease

Topics: Agar; Animals; Cats; Child; Diagnosis, Differential; Disease Reservoirs; Female; Germany, West; Griseofulvin; Humans; Legislation, Medical; Male; Microsporum; Middle Aged; Tinea; Tunisia

Topics: Agar; Animals; Chloramphenicol; Culture Media; Cycloheximide; Drug Resistance, Microbial; Guinea Pigs; Injections, Subcutaneous; Male; Tinea; Tolnaftate; Triamcinolone Acetonide; Trichophyton; Virulence

Topics: Agar; Animals; Bahamas; Glucose; Hair; Horses; Humans; Keratins; Microsporum; Penicillium; Soil Microbiology; Tinea; Trichophyton

Topics: Agar; Animals; Edible Grain; Genetic Variation; Genetics, Microbial; Glucose; Guinea Pigs; Humans; Hydroxides; Male; Melanesia; Methylene Blue; Middle Aged; Milk; Nicotinic Acids; Peptones; Pigments, Biological; Plants, Edible; Potassium; Spores, Fungal; Temperature; Tinea; Trichophyton; Urea

Topics: Agar; Animals; Glucose; Guinea Pigs; Humans; Infant; Male; Microsporum; Skin; Soil Microbiology; Spores, Fungal; Tinea

Topics: Agar; Animals; Child; England; Eulipotyphla; Guinea Pigs; Humans; Leg Dermatoses; New Zealand; Soil Microbiology; Species Specificity; Spores, Fungal; Tinea; Trichophyton; Urease

Topics: Agar; Animals; Blood; Culture Techniques; Horse Diseases; Horses; Male; Microsporum; Potassium Iodide; Tinea

Topics: Agar; Animals; Chromatography, Paper; Eukaryota; Fluorescence; Glucose; Guinea Pigs; Hair; Methods; Microsporum; Pteridines; Species Specificity; Spectrum Analysis; Tinea; Tissue Extracts; Ultraviolet Rays

Topics: Agar; Animals; Complement Fixation Tests; Glucose; Guinea Pigs; Hemagglutination Tests; Humans; Immune Sera; Immunodiffusion; Mice; Microsporum; Rabbits; Romania; Skin Tests; Soil Microbiology; Tinea

Topics: Adult; Agar; Aged; Culture Media; Female; Genetic Variation; Genetics, Microbial; Germany, East; Glucose; Humans; Male; Nigeria; Peptones; Pigments, Biological; Spores; Tinea; Trichophyton

Topics: Agar; Animals; Antifungal Agents; Candida; Culture Media; Dermatomycoses; Epidermophyton; Guinea Pigs; Humans; Photometry; Tinea; Trichophyton

Topics: Agar; Arthrodermataceae; Bacteria; Colistin; Cycloheximide; Diagnosis, Differential; Drug Resistance, Microbial; Humans; Novobiocin; Potassium; Pseudomonas aeruginosa; Tellurium; Tinea; Yeasts

Topics: Agar; Animals; Brain; Cattle; Glucose; Heart; Hydroxides; India; Inositol; Methods; Oryza; Potassium; Thiamine; Tinea; Trichophyton

Topics: Adolescent; Adult; Agar; Child; Child, Preschool; Europe; Female; Humans; Male; Onychomycosis; Tinea; Tinea Pedis; Trichophyton

Topics: Agar; Amebicides; Antifungal Agents; Aspergillosis; Candidiasis; Dermatomycoses; Drug Synergism; Humans; Microsporum; Quinolines; Resorcinols; Tinea