Onychomycosis in children: Safety and efficacy of antifungal agents

Onychomycosis

Onychomycosis is a fungal infection of the nail, and the most common nail infection worldwide, causing discoloration and thickening of the nail plate. It is predominantly caused by dermatophytes. Clinical presentation is polymorphous. Diagnosis must be confirmed by mycological examination before initiating any therapy. Management is an ongoing challenge, often requiring several months' treatment, with a high risk of recurrence. Treatment must be adapted to clinical presentation and severity and to the patient's history and wishes. Debridement of all infected keratin is the first step, reducing fungal load. Systemic treatments are more effective than topical treatments, and combining the two increases the cure rate. Terbinafine is the drug of choice for dermatophyte onychomycosis, due to low drug interaction and good cost-effectiveness. Itraconazole and fluconazole are broad-spectrum antifungals that are effective against dermatophytes, yeasts, and some non-dermatophytic molds. Recurrence rates for onychomycosis are high. Prophylactic application of topicals and avoiding walking barefoot in public places may help prevent recurence.

Recent drug development and treatments for fungal infections

Fungal infections are now becoming a hazard to individuals which has paved the way for research to expand the therapeutic options available. Recent advances in drug design and compound screening have also increased the pace of the development of antifungal drugs. Although several novel potential molecules are reported, those discoveries have yet to be translated from bench to bedside. Polyenes, azoles, echinocandins, and flucytosine are among the few antifungal agents that are available for the treatment of fungal infections, but such conventional therapies show certain limitations like toxicity, drug interactions, and the development of resistance which limits the utility of existing antifungals, contributing to significant mortality and morbidity. This review article focuses on the existing therapies, the challenges associated with them, and the development of new therapies, including the ongoing and recent clinical trials, for the treatment of fungal infections. Advancements in antifungal treatment: a graphical overview of drug development, adverse effects, and future prospects.

Children onychomycosis, a neglected dermatophytosis: A retrospective study of epidemiology and treatment

BACKGROUND

Onychomycosis was an ignored disease in children, and the prevalence was still unknown worldwide.

OBJECTIVES

This study was conducted to investigate the prevalence and treatment regimens of onychomycosis in children younger than 18 years old.

METHODS

We systemically reviewed all publications by searching the key terms to reveal the onychomycosis in children from 1990 to 2022.

RESULTS

A total of 44 articles including 2,382 children with onychomycosis were enrolled in this study. The male to female ratio was 1.29:1. The youngest child was 35 days old and the average age was 9.8 years old. The duration of disease usually ranged from 7 days to 4 years. Onychomycosis in children was more prevalent in toenails compared to fingernails (77.6% vs. 18.4%), and 4% patients had both. A total of 527 children (22.12%) had concomitant tinea pedis infection, and in 267 patients (11.21%), their family members had onychomycosis or tinea pedis. The most common clinical type of onychomycosis was DLSO (67.74%) and the predominant isolates were T. rubrum (66.13%), followed by C. albicans (9.08%) and T. mentagrophytes complex (5.34%). There were 419 children (74.03%) receiving systematic treatment only, 74 patients (13.07%) receiving topical treatment only, and 73 patients (12.90%) receiving both systematic and topical treatment. Twelve patients (2.12%) had mild drug-related side effects. During the follow-up, 71.25% children were cured, 17.50% symptoms improved and 4.17% failed.

CONCLUSIONS

Onychomycosis was underestimated in children and the diagnosis of onychomycosis should be properly considered in children with nail disorders. For mild patients, topical treatment can be a good choice, and oral antifungal drugs could be added to severe individuals under monitoring.

Green natural nail polish modified with essential oils to treat onychomycosis

BACKGROUND

Onychomycosis (OM) accounts for about 50% of nail disorders in industrialised countries. Essential oils (EOs), aromatic natural compounds, are known for their antimicrobial activity.

OBJECTIVE

The aim of this work was to evaluate the antifungal efficacy of seven EOs and a commercial MIX against 10 dermatophytes responsible for OM to select the most effective ones to be included in a preventive or curative formulation based on a green natural nail polish (GNNP).

METHODS

Micro-broth dilution tests in line with EUCAST guidelines and olfactory satisfaction test were performed to select the best natural compounds previously analysed by SPME coupled with GC-MS. The same method was used to evaluate the release over time of the active compounds present in the two modified-GNNPs made by adding the best natural compound selected (the C. citratus EO) and the MIX. Furthermore, to evaluate the preventive and curative activity of modified-GNNPs, ex vivo experiments on healthy or colonised nails were performed.

RESULTS AND CONCLUSIONS

Data showed that MIX-modified-GNNP had preventive activity as it inhibits the fungal growth by releasing its active ingredients for 7 days, while the OE-modified GNNP acts as a natural drug showing cytocidal activity on nails colonised by dermatophytes, but it requires two weekly applications.

Updated Perspectives on the Diagnosis and Management of Onychomycosis

Onychomycosis is the most common nail disease encountered in clinical practice and can cause pain, difficulty with ambulation, and psycho-social problems. A thorough history and physical examination, including dermoscopy, should be performed for each patient presenting with nail findings suggestive of onychomycosis. Several approaches are available for definitive diagnostic testing, including potassium hydroxide and microscopy, fungal culture, histopathology, polymerase chain reaction, or a combination of techniques. Confirmatory testing should be performed for each patient prior to initiating any antifungal therapies. There are several different therapeutic options available, including oral and topical medications as well as device-based treatments. Oral antifungals are generally recommended for moderate to severe onychomycosis and have higher cure rates, while topical antifungals are recommended for mild to moderate disease and have more favorable safety profiles. Oral terbinafine, itraconazole, and griseofulvin and topical ciclopirox 8% nail lacquer, efinaconazole 10% solution, and tavaborole 5% solution are approved by the Food and Drug Administration for treatment of onychomycosis in the United States and amorolfine 5% nail lacquer is approved in Europe. Laser treatment is approved in the United States for temporary increases in clear nail, but clinical results are suboptimal. Oral fluconazole is not approved in the United States for onychomycosis treatment, but is frequently used off-label with good efficacy. Several novel oral, topical, and over-the-counter therapies are currently under investigation. Physicians should consider the disease severity, infecting pathogen, medication safety, efficacy and cost, and patient age, comorbidities, medication history, and likelihood of compliance when determining management plans. Onychomycosis is a chronic disease with high recurrence rates and patients should be counseled on an appropriate plan to minimize recurrence risk following effective antifungal therapy.

Relevant insights into onychomycosis' pathogenesis related to the effectiveness topical treatment

Onychomycosis (OM) is a fungal infection, responsible for about 50% of nail diseases. OM has been attributed to the ability of fungi to naturally organize themselves into biofilms on nail surfaces. However, little is known about the exact role of the biofilm in the etiopathogenesis of OM, as well as its influence in the permeation of a topical treatment. The objectives of this study were to review the literature for topical OM treatments in clinical trials, assess the efficiency of these treatments, and discuss factors that could affect the success of these treatments. First, a systematic search of articles published in the MEDLINE database (PubMed) between January 2010 and December 2019 was conducted, focusing on drugs under clinical trials for the topical treatment of OM. Of the publications selected, it was clear that none of them had considered the fungi organized in biofilm. Therefore, we reflected on some important variables involved in OM, such as the nail structure and the mechanism of fungal invasion. Some methods, such as histopathologic analysis and spectroscopy techniques, were found to be effective in the detection of nail biofilm, and could be used in future drug permeation studies. This review allowed us to conclude that novel antifungals for the topical treatment of OM must consider the drug to permeate through biofilm. Natural products, such as propolis, seem strong candidates in this respect.

In vitro activities of 8 antifungal agents against geophilic dermatophyte isolates

BACKGROUND

Members of the Nannizzia gypsea complex are globally the most common geophilic dermatophytes which cause infection in animals and human. Although the susceptibility patterns of anthropophilic or zoophilic dermatophyte species to antifungal agents are well documented, the effectiveness of such drugs against geophilic species have rarely been explored.

OBJECTIVES

This study was aimed to evaluate the in vitro antifungal activity of common and new antifungals against a set of environmental and clinical geophilic dermatophyte isolates.

METHODS

108 soil and clinical geophilic isolates from two genera Nannizzia (N. fulva n = 59; N. gypsea n = 43) and Arthroderma (A. quadrifidum n = 4; A. gertleri n = 1; A. tuberculatum n = 1) were included in the study. The in vitro antifungal susceptibility patterns of eight common and new antifungals against the isolates were determined according to broth microdilution method and by CLSI M38-A3 (3rd edition) protocol.

RESULTS

MIC values across all isolates from five species ranged as: luliconazole: 0.0002-0.002 µg/ml, terbinafine: 0.008-0.125 µg/ml, efinaconazole: 0.008-0.125 µg/ml, ciclopirox olamine: 0.03-0.5 µg/ml, itraconazole: 0.125-1 µg/ml, amorolfine hydrochloride: 0.125-4 µg/ml, griseofulvin: 0.25-2 µg/ml and tavaborole: 1-8 µg/ml, respectively.

CONCLUSION

Luliconazole, terbinafine and efinaconazole exhibited the highest in vitro efficacy, regardless of the dermatophyte species. Further surveillance studies are recommended to confirm the implication of such in vitro data for the clinical recovery rate of dermatophytosis with geophilic species following antifungal therapy.

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.

Onychomycosis: An Updated Review

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.

Onychomycosis in children - review on treatment and management strategies

BACKGROUND

Onychomycosis is an uncommon condition in children with increasing global prevalence. Health practitioners should confirm the diagnosis through mycology examination and examine family members of affected individuals for onychomycosis and tinea pedis.

OBJECTIVE

To comprehensively summarize the treatment and management strategies for pediatric onychomycosis.

METHODS

We performed a comprehensive literature search in the PubMed database to identify clinical studies on treatment for mycologically-confirmed dermatophyte onychomycosis in children <18 years. The exclusion criteria were combination therapy, case reports, reviews, systematic reviews and duplicate studies.

RESULTS

Per-weight dosing regimens of systemic antifungal agents such as terbinafine, itraconazole, and fluconazole are found to be safe in children and are used off-label for the treatment of pediatric onychomycosis with high efficacy. Topical antifungal agents such as ciclopirox, efinaconazole, and tavaborole have established safety and efficacy in children. Children respond better than adults to topical therapy due to their thinner, faster growing nails. There is no data on the efficacy of medical devices for onychomycosis in children.

CONCLUSION

Efinaconazole topical solution 10% and tavaborole topical solution 5% are FDA approved for the treatment of onychomycosis in children ≥6 years; ciclopirox topical solution 8% nail lacquer is approved in children ≥12 years.

Pediatric nail disorders: a review

PURPOSE OF REVIEW

Nail disorders represent an uncommon subset of complaints seen in pediatric dermatology. There is a wide array of disorders that can affect the nail unit in children, including infectious, inflammatory, neoplastic, congenital, and traumatic processes. In order to enhance familiarity with pediatric nail conditions, we review the background and treatment of the more common entities seen in pediatric onychology, including onychomycosis, onychomadesis, nail psoriasis, trachyonychia, longitudinal melanonychia, onychophagia, and onychocryptosis.

RECENT FINDINGS

Nail involvement in pediatric patients with psoriasis may indicate increased risk for both overall disease severity and the development psoriatic arthritis. In the evaluation of longitudinal melanonychia, the clinical findings that raise concern for subungual melanoma in adults are often found in benign nail unit nevi in children. In the systemic treatment of pediatric onychomycosis, new data raises the possibility that laboratory monitoring may be approached differently. In the approach to onychophagia, emerging pharmacotherapies include N-acetylcysteine.

SUMMARY

Most nail disorders in pediatric patients have an overall favorable prognosis. However, nail abnormalities can lead to patient and parental anxiety, decreased quality of life, pain, and functional impairment. Clinicians should be aware of these more common diverse entities in order to identify them and apply state of the art management for these issues. Additionally, the reader will learn factors related to these nail disorders, which may require systemic work-up and/or specialist referral.

Labeled use of efinaconazole topical solution 10% in treating onychomycosis in children and a review of the management of pediatric onychomycosis

Onychomycosis is a difficult to treat condition whose prevalence is increasing. Until recently, there was no FDA approved antifungal agent for the treatment of onychomycosis in children. Although systemic antifungal agents are effective, their use is restricted by the potential adverse events and drug-drug interactions. There is evidence regarding the safety and efficacy of topical antifungal agents for pediatric onychomycosis. We have summarized the results of a recently published study using efinaconazole topical solution 10% to treat onychomycosis in children and discuss management of pediatric onychomycosis. In a multicenter, open-label phase 4 study, efinaconazole 10% solution was applied topically once daily in children aged 6 to 16 years with mild to severe, culture positive, distal and lateral subungual onychomycosis. Treatment was for 48 weeks with a follow-up at week 52. Pharmacokinetics was performed in a subset of patients. There were 62 patients enrolled in the study. At week 52, the efficacy was mycological cure rate 65% and complete cure rate 40%. All treatment-emergent adverse events (TEAE) were mild to moderate in severity with none resulting in study discontinuation. The only treatment-related TEAE was ingrown toenail. Efinaconazole was detected at low levels in plasma. Efinaconazole topical solution 10% is effective and safe in treating onychomycosis in children age 6 to 16 years and was recently FDA-approved for this indication. The on-label use of other topical agents, tavaborole solution 5% and ciclopirox nail lacquer solution 8% is reviewed. We also briefly discuss the use of oral agents, terbinafine, itraconazole, and fluconazole in pediatric onychomycosis.

A Week of Oral Terbinafine Pulse Regimen Every Three Months to Treat all Dermatophyte Onychomycosis

Terbinafine has proved to treat numerous fungal infections, including onychomycosis, successfully. Due to its liver metabolization and dependency on the cytochrome P450 enzyme complex, undesirable drug interaction are highly probable. Additionally to drug interactions, the treatment is long, rising the chances of the appearance of side effects and abandonment. Pharmacokinetic data suggest that terbinafine maintains a fungicidal effect within the nail up to 30 weeks after its last administration, which has aroused the possibility of a pulse therapy to reduce the side effects while treating onychomycosis. This study's goal was to evaluate the effectiveness of three different oral terbinafine regimens in treating onychomycosis due to dermatophytes. Sixty-three patients with onychomycosis were sorted by convenience in three different groups. Patients from group 1 received the conventional terbinafine dose (250 mg per day for 3 months). Group 2 received a monthly week-long pulse-therapy dose (500 mg per day for 7 days a month, for 4 months) and group 3 received a 500 mg/day dose for 7 days every 3 months, totaling four treatments. There were no statistical differences regarding the effectiveness or side effects between the groups. Conclusion: A quarterly terbinafine pulse regimen can be a possible alternative for treating onychomycosis caused by dermatophytes.

Global perspectives for the management of onychomycosis

Onychomycosis is a fungal nail infection caused by dermatophytes, nondermatophyte molds, and yeasts. This difficult-to-treat chronic infection has a tendency to relapse despite treatment. This paper aims to offer a global perspective on onychomycosis management from expert physicians from around the world. Overall, the majority of experts surveyed used systemic, topical, and combination treatments approved in their countries and monitored patients based on the product insert or government recommendations. Although the basics of treating onychomycosis were similar between countries, slight differences in onychomycosis management between countries were found. These differences were mainly due to different approaches to adjunctive therapy, rating the severity of disease and use of prophylaxis treatment. A global perspective on the treatment of onychomycosis provides a framework of success for the committed clinician with appreciation of how onychomycosis is managed worldwide.