Onychomycosis: Which fungal species are involved? Experience of the Laboratory of Parasitology-Mycology of the Rabta Hospital of Tunis

Lam

et al. 2020

IAD

Background : Onychomycosis is a common fungal infection of the nail. Objective: The study aimed to provide an update on the evaluation, diagnosis, and treatment of onychomycosis. Methods: A PubMed search was completed in Clinical Queries using the key term “onychomycosis”. The search was conducted in May 2019. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews published within the past 20 years. The search was restricted to English literature. Patents were searched using the key term “onychomycosis” in www.freepatentsonline.com. Results : Onychomycosis is a fungal infection of the nail unit. Approximately 90% of toenail and 75% of fingernail onychomycosis are caused by dermatophytes, notably Trichophyton mentagrophytes and Trichophyton rubrum. Clinical manifestations include discoloration of the nail, subungual hyperkeratosis, onycholysis, and onychauxis. The diagnosis can be confirmed by direct microscopic examination with a potassium hydroxide wet-mount preparation, histopathologic examination of the trimmed affected nail plate with a periodic-acid-Schiff stain, fungal culture, or polymerase chain reaction assays. Laboratory confirmation of onychomycosis before beginning a treatment regimen should be considered. Currently, oral terbinafine is the treatment of choice, followed by oral itraconazole. In general, topical monotherapy can be considered for mild to moderate onychomycosis and is a therapeutic option when oral antifungal agents are contraindicated or cannot be tolerated. Recent patents related to the management of onychomycosis are also discussed. Conclusion: Oral antifungal therapies are effective, but significant adverse effects limit their use. Although topical antifungal therapies have minimal adverse events, they are less effective than oral antifungal therapies, due to poor nail penetration. Therefore, there is a need for exploring more effective and/or alternative treatment modalities for the treatment of onychomycosis which are safer and more effective.

Section: Etiologymentioning

confidence: 99%

Section: Etiologymentioning

confidence: 99%

Onychomycosis: An Updated Review

Lam

et al. 2020

IAD

“…Non-dermathophyte molds cause 20%-30% of nail infections, mainly in toenails, and usually after previous nail traumas. These pathogens belong to genera such as Fusarium, Aspergillus, Acremonium, Scytalidium and Scopulariopsis [3,8,9]. Finally, yeasts cause 10% to 20% of all onychomycosis, with main species being Candida albicans (accounting for 70% of all yeast onychomycosis), C. tropicalis and C. parapsilosis, mainly in immunosuppressed patients or those ones with vascular problems [10][11][12][13].…”

Section: Introductionmentioning

confidence: 99%

Combined laser and ozone therapy for onychomycosis in an in vitro and ex vivo model

Fernández

Fernández²,

Villar

et al. 2021

PLoS ONE

In order to develop a fast combined method for onychomycosis treatment using an in vitro and an ex vivo models, a combination of two dual-diode lasers at 405 nm and 639 nm wavelengths, in a continuous manner, together with different ozone concentrations (until 80 ppm), was used for performing the experiments on fungal strains growing on PDA agar medium or on pig’s hooves samples. In the in vitro model experiments, with 30 min combined treatment, all species are inhibited at 40 ppm ozone concentration, except S. brevicaulis, which didn’t show an inhibition in comparison with only ozone treatment. In the ex vivo model experiments, with the same duration and ozone concentration, A. chrysogenum and E. floccosum showed total inhibition; T. mentagrophytes and T. rubrum showed a 75% growth inhibition; M. canis showed a delay in sporulation; and S. brevicaulis and A. terreus did not show growth inhibition. This combined laser and ozone treatment may be developed as a fast therapy for human onychomycosis, as a potential alternative to the use of antifungal drugs with potential side effects and long duration treatments.

“…Conventional methods to confirm the presence of a fungal infection involve clipping or scraping samples of nail followed by mycological culture. With mild infections, the affected area of the nail may not be in close proximity to an accessible nail edge from which a sample can be easily obtained, furthermore, culture of Trichophyton rubrum , the species responsible for 96.8% of fungal nail infections involving the toes is not always successful . Samples obtained from patients with mild infections often contain too few fungal spores to generate a culture of the causative fungus which can lead to false negatives .…”

Section: Introductionmentioning

confidence: 99%

“…Conversely, Candida species are often recovered from toenail samples and readily cultured under laboratory conditions. Candida species, however, predominantly infect nails of the hands; therefore, mycological testing for the presence of Candida is inappropriate when monitoring the progress of toenail infections. These difficulties in culturing and identifying the causative organism mean that laboratory identification is often not performed and the alternative to mycological testing involves a visual assessment by a podiatrist and classification using grading scales.…”

Section: Introductionmentioning

confidence: 99%

A prospective study using image analysis to assess the efficacy of a topical treatment kit for mild onychomycosis

Khammo

Chesters

Goldstone

et al. 2019

Mycoses

Summary Background Onychomycosis is a fungal infection of the nails and is one of the most common dermatological infections worldwide. Infection occurs predominantly in the nails of the feet and if left untreated patients, particularly in at‐risk populations, can develop more serious complications, including pain, fissuring and secondary infections. Fungal infections are also contagious and may spread to other nails or to family members. Topical treatments can be effective for mild cases of the disease and typically have fewer contraindications. However, generation of robust efficacy data for topical therapies is often hindered by the difficulties associated with monitoring progression of mild onychomycosis using the conventional methods of mycological culture to obtain confirmation of podiatrist assessments. Objectives The aim of this study was to demonstrate image analysis as an effective method to monitor progression of fungal nail infections. Methods A novel digital image analysis technique was used to evaluate improvement in the visual signs of onychomycosis, when using a topical treatment kit for mild fungal nail infections in 60 participants over a 280‐day period. Results Image analysis demonstrated a significant (P < .0001) reduction from baseline of the affected nail area throughout the study period, results which were also perceived by the subjects themselves. Use of the treatment kit also limited the deterioration of the infection and prevented transmission to other nails. Conclusions Image analysis was established as a viable method to monitor the progression of fungal nail infections over long periods and demonstrate a clinical benefit following treatment.