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The viability of pathogenic fungi in the scale was investigated during topical administration of 1% luliconazole (LLCZ). Thirteen tinea pedis patients found to be positive on KOH examination were assessed by mycological examinations and quantitative real-time polymerase chain reaction (PCR) targeted internal transcribed spacer (ITS) in ribosomal RNA gene at the initial visit and after 2 and 4 weeks of treatment. Assays showed that the average copy number of ITS DNA had significantly decreased to 22.9% at 2 weeks and 4.8% at 4 weeks compared with the initial visit. LLCZ topical treatment could defeat almost pathogenic dermatophytes in the scales within 4 weeks., (© The Author(s) 2019. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

Tinea capitis is a contagious dermatophyte infection of scalp and associated hairs. On the other hand, asymptomatic carriage is a status of positive dermatophyte scalp culture, but without signs or symptoms of tinea capitis, and no evidence of hair shaft invasion confirmed by direct microscopy. Tinea capitis and asymptomatic carriage mostly occur in children, but adult females are becoming another population in recent decades. In this study, we focused on the prevalence and related fungi of tinea capitis and asymptomatic carriage in elderly by the shampoo brush method, as well as the source of transmission, in 10 nursing home residents. Two hundred and thirteen residents were screened, and 186 isolates were identified, of which only three were dermatophytes (1.4%). The scalp dermatophyte isolates were identified as Trichophyton rubrum by morphological characters and sequences comparisons in all three cases. After revisiting, these cases were proved to be asymptomatic carriers by negative microscopic and culture examination; however, two cases were found to have concurrent tinea pedis and onychomycosis, which were identified as T. rubrum and Trichophyton interdigitale. The source of the T. rubrum scalp carriage may come from tinea elsewhere on the body of the same subject or from other people in the same institute. Finding and treating the source of carriage, as well as treating scalp carriage patients according to the colony counts, may help prevent disease spreading., (© The Author 2017. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In the framework of a survey on dermatophytoses, 14,619 clinical specimens taken from outpatients with symptoms suggestive of tinea and referred to a Medical Mycology laboratory in Tehran, Iran, were analyzed by direct microscopy and culture. In total, 777 dermatophyte strains recovered in culture were randomly identified by a formerly established RFLP analysis method based on the rDNA ITS regions. For confirmation of species identification, 160 isolates representing the likely entire species spectrum were subjected to ITS-sequencing. Infection was confirmed in 5,175 collected samples (35.4%) by direct microscopy and/or culture. Tinea pedis was the most prevalent type of infection (43.4%), followed by tinea unguium (21.3%), tinea cruris (20.7%), tinea corporis (9.4%), tinea manuum (4.2%), tinea capitis (0.8%) and tinea faciei (0.2%). Trichophyton interdigitale was the most common isolate (40.5%) followed by T. rubrum (34.75%), Epidermophyton floccosum (15.6%), Microsporum canis (3.9%), T. tonsurans (3.5 %) and M. gypseum (0.5%). Other species included M. ferrugineum, T. erinacei, T. violaceum, T. schoenleinii, and a very rare species T. eriotrephon (each one 0.25%). The two strains of T. eriotrephon isolated from tinea manuum and tinea faciei are the second and third reported cases worldwide. Application of DNA-based methods is an important aid in monitoring trends in dermatophytosis in the community.

Aims: To test a nitric oxide-releasing solution (NORS) as a potential antifungal footbath therapy against Trichophyton mentagrophytes and Trichophyton rubrum during the mycelial and conidial phases., Methods and Results: NORS (sodium nitrite citric acid) produces nitric oxide verified by gas chromatography and mass spectrometry (GC-MS). Antifungal activity of this solution was tested against mycelia and conidia of T. mentagrophytes and T. rubrum, using 1-20 mmol l(-1) nitrites and 10-30 min exposure times. The direct effect of the gas released from the solution on the viability of those fungi was tested. NORS demonstrated strong antifungal activity and was found to be dose and time dependent. NO and nitrogen dioxide (NO(2) ) were the only gases detected from this reaction and are likely responsible for the antifungal effect., Conclusions: This in vitro research suggests that a single 20-min exposure to NORS could potentially be used as an effective single-dose treatment against fungi that are associated with tinea pedis in both mycelia and spore phase., Significance and Impact of the Study: This study provides the background for developing a user-friendly footbath treatment for Athlete's Foot that will kill both vegetative fungi and its spores., (© 2012 The Society for Applied Microbiology.)

Previous studies have described some antibacterial effects of antimicrobial peptides (AMPs) expressed in human skin, but little is known about their possible activity against dermatophytes. Therefore we have tested the effects of human β-defensin 2 (hBD-2), ribonuclease 7 (RNase 7) and psoriasin on the in vitro growth of four dermatophyte species. Germinating conidia of Trichophyton rubrum, T. mentagrophytes, Microsporum canis and Epidermophyton floccosum were exposed in vitro to hBD-2, RNase 7, psoriasin and fluconazole. Subsequent fungal growth was measured photometrically over 168 hours. All AMPs significantly inhibited fungal growth, with the degree of inhibition dependent on the dermatophyte species and the specific AMP. E. floccosum was found to be the most susceptible species in that it was markedly suppressed by all AMPs, whereas M. canis was inhibited only by psoriasin. Overall, psoriasin was the most effective AMP and had even stronger inhibitory effects on some dermatophytes than fluconazole. Our findings show that AMPs expressed in human skin can, in principal, inhibit the growth of dermatophytes in vitro. Therefore the question whether AMPs are relevant for human protection against tineas is justified and should be addressed by investigating their role in vivo.

Background: Onychomycosis is a common cause of nail dystrophy and may be associated with tinea pedis. The presence of dermatophyte fungi in clinically normal nails is unknown., Objectives: To assess the presence of dermatophyte fungi in normal-appearing toenails and to compare the risk of subclinical dermatophytosis in patients without and with concurrent tinea pedis., Methods: This is a prospective, University-based study of adults without and with microscopically confirmed tinea pedis. Subjects with dystrophy of any toenail were excluded, as were those ever previously diagnosed as having onychomycosis and those who had used topical antifungals in the past year. A great toenail clipping obtained from each subject was submitted for periodic acid-Schiff histology., Results: One hundred and one subjects (63 men and 38 women, mean +/- SD age 45.4 +/- 15.7 years) were included. Overall, septate hyphae (ostensibly dermatophyte) were identified in seven specimens. Of the 66 control subjects, one case (1.5%) of nail dermatophyte was identified. Of the 35 subjects with tinea pedis, six cases (17%) of nail dermatophyte were identified (P = 0.0066; odds ratio 13.4, 95% confidence interval 1.6-117). There were no significant differences in age or gender between the experimental and control groups or between the nail dermatophyte-positive and negative cohorts., Conclusions: Dermatophyte fungi may be isolated from normal-appearing toenails. The presence of dermatophytes in this situation is strongly associated with the presence of tinea pedis. Subclinical dermatophyte in the nail plate may serve as a reservoir for ongoing local infection.

Dermatophytosis is the most common skin infection caused by dermatophytic fungi, such as Trichophyton spp. We studied the in vitro and in vivo antifungal effects of lactoferrin against Trichophyton. Human and bovine lactoferrin, and a bovine lactoferrin-derived peptide, lactoferricin B, showed in vitro antifungal activity that was dependent on the test strain and medium used. In guinea pigs infected on the back with Trichophyton mentagrophytes (i.e. those with tinea corporis), consecutive daily po administration of bovine lactoferrin did not prevent development of symptoms during the early phase of infection, but facilitated clinical improvement of skin lesions after the peak of the symptoms. The fungal burden in lesions was less in guinea pigs that had been given lactoferrin than in untreated controls 21 days after infection. In guinea pigs infected on the foot with T. mentagrophytes (i.e. those with tinea pedis), the fungal burden of the skin on the heel portion of the infected foot 35 days after infection was lower in animals fed lactoferrin than in controls. These results suggest the potential usefulness of lactoferrin as a food component for promoting dermatophytosis cure.

A clear understanding of the pathogenesis of fungal disease remains elusive. While technological advances in molecular biology and microbial genetics have provided scientists with major new insights into both microbial virulence factors as well as host susceptibility to infection, there is currently no substitute for animal models in elucidating microbe-host interactions. Animal models are also essential for the evaluation of new antimicrobial agents, including studies of efficacy, adverse reactions and pharmacokinetics. The single most important advance in animal models in the last decade, has been the availability of genetically unique strains of animals as alternative to animals treated with immunosuppressive drugs for use in studies on microbial virulence and host defence mechanisms. These unique strains of test animals also enhance our understanding of the modes of action of antifungal drugs and their metabolism. Some of these advances will be discussed in this symposium.

The therapeutic efficacy of omoconazole nitrate was investigated in an experimental tinea pedis model produced by topical inoculation with Trichophyton mentagrophytes in guinea-pigs, which is pathologically similar to naturally infected tinea pedis in humans. Treatment with omoconazole nitrate cream was started on week 2 postinfection and continued for 3 or 4 weeks. Once-a-day application of 1% omoconazole nitrate to the site of infection exhibited an excellent therapeutic efficacy, and was superior to 1% bifonazole cream in culture result. This result suggests that omoconazole nitrate has a potential usefulness for the treatment of tinea pedis in humans.

We performed a study to determine how often patients with cellulitis of the lower extremities in the absence of trauma, peripheral vascular disease, or chronic open ulcers have ipsilateral interdigital athlete's foot and whether cultures of samples from the involved interdigital spaces would yield potentially pathogenic bacteria. Athlete's foot was present in 20 (83%) of 24 episodes of cellulitis that were studied. Cultures of samples from interdigital spaces yielded Beta-hemolytic streptococci in 17 (85%) of 20 cases, Staphylococcus aureus in 9 (45%) of 20 cases, and gram-negative rods in 7 (35%) of 20 cases. Only Beta-hemolytic streptococci were recovered significantly more often from patients than from a group of controls with athlete's foot who did not have cellulitis (P < .01). Athlete's foot may be a common predisposing condition for cellulitis of the lower extremities. In comparison with attempts at microbiological diagnosis such as aspiration and/or biopsy of the area of cellulitis, cultures of samples from the interdigital spaces combined with serial determinations of antistreptolysin titers may offer a simpler noninvasive method of microbiological diagnosis.

A double-blind trial of 2% miconazole in a cream and in a powder base and of the respective vehicles was done in a group of forty-five young sportsmen regularly training and using the showers in a gymnasium. After 4 weeks treatment, the mycological cure rate using the active preparation was 60% compared to 24% for the placebo (P less than 0-05).