Diagnosis and Management of Onychomycosis Perspectives from a Joint Podiatric Medicine-Dermatology Roundtable

Risk factors for the development of tinea pedis and onychomycosis: Real-world evidence from a single-podiatry center, large-scale database in Japan

Dermatomycosis, including tinea pedis and onychomycosis, is frequently encountered in routine medical care in Japan. Identifying the risk factors for tinea pedis and onychomycosis development is important to encourage hospital visits by patients who may have these diseases but who are not undergoing any treatment. This approach may lead to the prevention of disease progression and the spread of infections to others. Risk factors for onychomycosis development have been reported both in and outside of Japan. However, most of the risk factors were identified based on a multicenter, questionnaire survey study and included evidence obtained from unclear or inconsistent diagnostic criteria for tinea pedis, onychomycosis, and identified risk factors. The current study analyzed the risk factors for developing tinea pedis and onychomycosis in real-world practice in Japan using a single-center, large-scale database that included the data of patients managed with consistent diagnostic criteria at the Podiatry Center of Juntendo University Hospital. A total of 2476 patients (1012 males, 1464 females) with a mean age of 63.4 years were included. Among these patients, 337 (13.6%) had tinea pedis and 346 (14.0%) had onychomycosis. A total of 259 patients (~ 75% of each patient population) had both diseases concomitantly. Multivariate logistic regression analysis adjusted for the possible risk factors of age (per 10 years), sex, diabetes, dialysis, visual impairment, ulcer history, lower-limb ischemia (LLI), and diabetic peripheral neuropathy (DPN) revealed that advanced age, male sex, diabetes, and LLI were independent risk factors for the development of tinea pedis. In addition, DPN was an independent risk factor for developing onychomycosis. We believe that these data are useful for identifying patients who are at high risk of developing tinea pedis and onychomycosis, which may result in disease prevention and suppression in real-world clinical practice in Japan.

Treatment of onychomycosis in an era of antifungal resistance: Role for antifungal stewardship and topical antifungal agents

A growing body of literature has marked the emergence and spread of antifungal resistance among species of Trichophyton, the most prevalent cause of toenail and fingernail onychomycosis in the United States and Europe. We review published data on rates of oral antifungal resistance among Trichophyton species; causes of antifungal resistance and methods to counteract it; and in vitro data on the role of topical antifungals in the treatment of onychomycosis. Antifungal resistance among species of Trichophyton against terbinafine and itraconazole-the two most common oral treatments for onychomycosis and other superficial fungal infections caused by dermatophytes-has been detected around the globe. Fungal adaptations, patient characteristics (e.g., immunocompromised status; drug-drug interactions), and empirical diagnostic and treatment patterns may contribute to reduced antifungal efficacy and the development of antifungal resistance. Antifungal stewardship efforts aim to ensure proper antifungal use to limit antifungal resistance and improve clinical outcomes. In the treatment of onychomycosis, critical aspects of antifungal stewardship include proper identification of the fungal infection prior to initiation of treatment and improvements in physician and patient education. Topical ciclopirox, efinaconazole and tavaborole, delivered either alone or in combination with oral antifungals, have demonstrated efficacy in vitro against susceptible and/or resistant isolates of Trichophyton species, with low potential for development of antifungal resistance. Additional real-world long-term data are needed to monitor global rates of antifungal resistance and assess the efficacy of oral and topical antifungals, alone or in combination, in counteracting antifungal resistance in the treatment of onychomycosis.

Poor Antifungal Coverage for Onychomycosis in a Cross-Sectional Analysis of Medicaid Formularies

BACKGROUND

Onychomycosis is the most common nail disease seen in clinical practice. Medication safety, severity of disease, comorbidities, concomitant medications, patient age, and cost are all important considerations when treating onychomycosis. Because cost may affect treatment decisions, we sought to analyze Medicaid formulary coverage of onychomycosis antifungals.

METHODS

Public state Medicaid formularies were searched for coverage of US Food and Drug Administration-approved onychomycosis medications and off-label oral fluconazole. Total drug cost for a single great toenail was calculated using the National Average Drug Acquisition Cost. Pearson correlation coefficients were calculated to compare coverage and cost, mycologic cure rate, and complete cure rate.

RESULTS

Oral terbinafine and off-label fluconazole were widely covered for onychomycosis treatment. There was poor coverage of oral itraconazole and topical ciclopirox, and there was no coverage of topical efinaconazole and tavaborole without step-edits or prior authorization. There was a significant negative correlation between medication coverage and cost (r = -0.758; P = .040). There was no correlation between medication coverage and mycologic (r = 0.548; P = .339) and complete (r = 0.768; P = .130) cure rates.

CONCLUSIONS

There is poor Medicaid coverage of antifungals for the treatment of onychomycosis, with step-edits and prior authorization based on cost rather than treatment safety and efficacy. We recommend involving podiatrists and dermatologists in developing criteria for insurance approval of onychomycosis treatments.

Total Dystrophic Onychomycosis Successfully Treated with Efinaconazole Topical Solution in Times of Coronavirus Disease of 2019: A Case Study

Toenail onychomycosis is a common condition that is equally challenging for podiatrists and patients. This case study documents a 26-year-old woman with bilateral total dystrophic onychomycosis of at least 5 years' duration. She had previously failed to respond to treatment with ciclopirox nail lacquer 8% and, despite hiding her condition with nail polish, was suffering from embarrassment, distress, and low self-esteem. At initial consultation, 100% of both great toenails was affected. After discussion of all treatment options, the patient opted for topical efinaconazole 10% solution, once daily for 48 weeks. Significant improvement was noted at the first (4-week) assessment period. This improvement was maintained through each subsequent virtual consultation, and complete cure was seen at a 30-week follow-up visit. To the author's knowledge, this is the first published report on the use of efinaconazole in total dystrophic onychomycosis. It suggests that the product may be effective in patients with even the most severe and treatment-recalcitrant disease, who are unwilling or unable to tolerate systemic antifungal therapy.

Diagnosing onychomycosis: A step forward?

BACKGROUND AND AIMS

There are a number of available methods for diagnosing onychomycosis, but more emerge as technology advances. This review briefly discusses the common diagnostic methods, the use of artificial intelligence (AI) as a diagnostic tool in dermatology as a whole, and then examines research on the use of AI for diagnosing onychomycosis. The studies discussed implemented convolutional neural networks (CNNs) to examine datasets of images of entire nails or histological images and then used the information learned from those datasets to make a diagnostic decision of onychomycosis or not.

RESULTS

Results: It was found that, on average, AI were able to diagnose onychomycosis from the images provided at an equivalent level as human dermatologists. However, there are a number of clear limitations for using AI in this manner. The AI models implemented relied solely on images and therefore were limited by image quality. As only images were examined, other clinical data were not taken into consideration, which could be important to the diagnostic outcome.

CONCLUSION

Conclusion: In conclusion, although AI can be a very helpful tool in the diagnostic process by increasing efficiency and reducing costs, it still requires the precision and expertise of professional dermatologists to be used optimally.

Efinaconazole topical solution (10%) for the treatment of onychomycosis in adult and pediatric patients

Introduction: Onychomycosis, a common nail disorder caused by fungal infection, can be managed pharmaceutically with oral or topical treatments. While oral treatments are often used first-line to treat nail infections, these systemic antifungals are not appropriate for all patients, and no oral treatments are approved for use in children in the USA. Given this need, topical antifungals were developed, which can be used as monotherapy or in combination with oral drugs.Areas Covered: Efinaconazole 10% solution is an azole antifungal indicated for topical treatment of toenail onychomycosis in pediatric and adult patients. This qualitative literature review summarizes available chemical, pharmacological, efficacy, safety, and post-marketing surveillance data of efinaconazole 10% topical solution. Efinaconazole 10% has been shown to be safe and efficacious regardless of disease severity/duration at baseline; patient gender, ethnicity, or age (including pediatrics); or comorbidities such as diabetes or tinea pedis. Overall, efinaconazole is a safe and effective clinical option for the treatment and management of onychomycosis.Expert Opinion: Efinaconazole is the first new antifungal approved for onychomycosis in 10 years in the USA. It has comparable efficacy to systemic antifungal agents such as itraconazole, and a favorable adverse events profile with minimal systemic exposure and no drug-drug interactions.

In vitro antifungal susceptibility testing of fungi in patients with onychomycosis

Onychomycosis is the most common nail disorder. To examine in vitro antifungal susceptibility of fungi among onychomycosis patients. The study included 68 patients with onychomycosis. Nail specimens were cultured on Sabouraud dextrose agar and Dermasel agar base-media. Isolated fungi were subjected to antifungal susceptibility tests against terbinafine, itraconazole, fluconazole, and griseofulvin. Candida species (Candida spp.) were detected in 32.4% of the cases of candidal onychomycosis (n = 37), 23.5% of the cases of distal and lateral subungual onychomycosis (n = 17), and 21.4% of the cases of total dystrophic onychomycosis (n = 14). Candida spp. were sensitive to fluconazole in 73.5%, itraconazole in 58.8%, and terbinafine in 5.9% of the cases. Aspergillus spp. were sensitive to itraconazole in all cases, and terbinafine in 87.5% of cases. Penicillium spp. were sensitive to itraconazole and terbinafine in 88.9% and 77.8% of cases, respectively. Trichophyton spp. were sensitive to terbinafine and resistant to itraconazole. Microsporum spp. were sensitive to itraconazole and resistance to terbinafine. All isolated fungi were resistant to griseofulvin. An increasing proportion of Candida spp. was observed among patients with different clinical varieties of onychomycosis. Candida spp. were highly sensitive to fluconazole and a lesser extent to itraconazole.

Oral antifungal therapies for toenail onychomycosis: a systematic review with network meta-analysis toenail mycosis: network meta-analysis

Aim: Toenail fungal infections account for half of all nail disease cases, and a highly negative impact on patient quality of life. Our aim was to compare the efficacy and safety of commercially available oral antifungals for onychomycosis.Methods: A systematic review was performed in PubMed and Scopus. Randomized controlled trials evaluating the effect of oral antifungals on mycological cure, discontinuation and adverse events were included. Network meta-analyses were built for each outcome. Results were reported as odds ratios (OR) with 95% credibility intervals (CrI). Ranking probabilities were calculated by surface under the cumulative ranking analysis (SUCRA).Results: We included 40 trials (n = 9568). Albaconazole 400 mg (OR 0.02 [95% CrI 0.01-0.07] versus placebo), followed by posaconazole 200-400 mg and terbinafine 250-350 mg were considered the best therapies (SUCRA probabilities over 75%). For the networks of discontinuation and individual adverse events, few significant differences among treatments were observed, but itraconazole 400 mg was considered the safest drug (SUCRA around 25%). Albaconazole 400 mg, posaconazole 200-400 mg, and terbinafine 250-350 mg were the most effective therapies for onychomycosis, while itraconazole 400 mg was the safest.Conclusion: The profile of albaconazole and posaconazole compared to current first-line therapies should be further investigated in well-designed trials.