A critical review of improvement rates for laser therapy used to treat toenail onychomycosis

Nd:YAG 1064 nm laser treatment for onychomycosis - is it really effective? A prospective assessment for efficiency and factors contributing to response

Onychomycosis is a highly prevalent and persistent nail disorder primarily caused by dermatophytes. The effectiveness of current topical and systemic antifungals is limited by the extent and severity of the infection, patient demographics and health status, hepatic toxicity, drug interactions and low compliance. Laser therapy is a promising modality for safe and cost-effective removal of mycotic nail. This prospective study assessed the performance of a multi-series long-pulsed Nd:YAG 1064 nm regimen (30-40 J/cm2 , 1 Hz) in the treatment of 213 mycotic nails in 31 patients. Pain and discomfort were scored at each treatment session and mycological and clinical cure rates were determined 3 months after the last treatment session. Patients presented with mostly severe (mean SCIO score: 21.9 ± 8.9), T. rubrum-positive (87.1%) infections. Most (61%) had a family history of onychomycosis and a significant proportion had comorbidities, including hypertension (38.7%), hyperlipidemia (35.5%) and/or diabetes (12.9%). Treatment was well tolerated and there were no reports of nail deformity or burns. By 3 months post-treatment, mycological cure was achieved by 4 (12.9%) and visual improvements were noted for 10 (32.3%) patients, including 3 (9.7%) with moderate to significant improvements. Clinical response correlated with baseline SCIO ≤ 20 (OR: 0.9 [0.13-6.52]), family history of onychomycosis (OR: 0.27 [0.04-1.50]) and comorbidities (OR: 0.44 [0.05-3.74]). In conclusion, Nd:YAG 1064 nm laser is safe and effective for the management of mild-to-moderate onychomycosis in diverse populations. Further studies will be necessary to adjust treatment parameters to patient and nail profiles and to determine the impact of combined laser and topical therapies.

Dermatophyte Infections Worldwide: Increase in Incidence and Associated Antifungal Resistance

The increase in incidence of superficial fungal infections combined with the emergence of antifungal resistance represents both a global health challenge and a considerable economic burden. Recently, dermatophytes, the main culprit causing superficial fungal infections, have started to exhibit antifungal resistance. This can be observed in some of the most common species such as Trichophyton rubrum and Trichophyton mentagrophytes. Importantly, the new subspecies, known as Trichophyton indotineae, has been reported to show high resistance to terbinafine, a first-line treatment for dermatophyte infections. Compounding these issues is the realization that diagnosing the causative infectious agents requires using molecular analysis that goes beyond the conventional macroscopic and microscopic methods. These findings emphasize the importance of conducting antifungal susceptibility testing to select the appropriate antifungal necessary for successful treatment. Implementing these changes may improve clinical practices that combat resistant dermatophyte infections.

Onychomycosis: Old and New

Onychomycosis is a common chronic fungal infection of the nail that causes discoloration and/or thickening of the nail plate. Oral agents are generally preferred, except in the case of mild toenail infection limited to the distal nail plate. Terbinafine and itraconazole are the only approved oral therapies, and fluconazole is commonly utilized off-label. Cure rates with these therapies are limited, and resistance to terbinafine is starting to develop worldwide. In this review, we aim to review current oral treatment options for onychomycosis, as well as novel oral drugs that may have promising results in the treatment of onychomycosis.

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.

Real-world Effectiveness of a Fractional CO2 Laser with Topical Antifungal Agents for the Treatment of Onychomycosis

BACKGROUND

Current therapeutic agents for onychomycosis have limited efficacy or cause side effects. Recently, successful treatment using fractional CO₂ lasers has been reported; however, the results are inconsistent.

OBJECTIVE

We analyzed the real-world effectiveness of a Fractional CO₂ laser for the treatment of Onychomycosis METHODS: A single-center retrospective chart review was conducted during January 2015-December 2018. Patients, diagnosed with onychomycosis through fungal culture and/or potassium hydroxide staining, underwent three or more fractional CO₂ laser treatments and used topical antifungal agents. Treatment effects were assessed by using clinical images at 6 months, 12 months, and the last visit.

RESULTS

Ninety-six patients were included; they underwent an average of 7.7 laser treatment sessions. Finally, 15 patents (15.6%) showed complete response (CR, 100% clearing of all nails), 24 patients (25%) showed partial response, and 57 patients (59.4%) showed no response (no 100% clearing of nails among all treated toenails per patient including mild improvement or temporary cosmetic improvement). Multivariable logistic regression analysis revealed longer disease duration (P=0.006, OR=1.16(95% CI: 1.05-1.31)), patients with diabetes (P=0.021, OR=9.82(95% CI:1.75-94.01)) and fewer number of laser treatment sessions (P=0.001, OR=0.76(95% CI:0.64-0.89)) were significantly associated with non-response group.

CONCLUSIONS

In conclusion, fractional CO2 laser with topical antifungal could be a safe alternative treatment in patients with onychomycosis, who are difficult to take oral antifungals. This article is protected by copyright. All rights reserved.

Efficacy of Lasers for the Management of Dermatophyte Toenail Onychomycosis

BACKGROUND

Onychomycosis is a chronic fungal nail infection caused predominantly by dermatophytes, and less commonly by nondermatophyte molds and Candida species. Onychomycosis treatment includes oral and topical antifungals, the efficacy of which is evaluated through randomized, double-blind, controlled trials for US Food and Drug Administration approval. The primary efficacy measure is complete cure (complete mycologic and clinical cure). The secondary measures are clinical cure (usually ≤10% involvement of target nail) and mycologic cure (negative microscopy and culture). Some lasers are US Food and Drug Administration approved for the mild temporary increase in clear nail; however, some practitioners attempt to use lasers to treat and cure onychomycosis.

METHODS

A systematic review of the literature was performed in July of 2020 to evaluate the efficacy rates demonstrated by randomized controlled trials of laser monotherapy for dermatophyte onychomycosis of the great toenail.

RESULTS

Randomized controlled trials assessing the efficacy of laser monotherapy for dermatophyte toenail onychomycosis are limited. Many studies measured cure rates by means of nails instead of patients, and performed only microscopy or culture, not both. Only one included study reported mycologic cure rate in patients as negative light microscopy and culture (0%). The combined clinical cure rates in short- and long-pulsed laser studies were 13.0%-16.7% and 25.9%, respectively. There was no study that reported the complete cure rate; however, one did report treatment success (mycologic cure [negative microscopy and culture] and ≤10% clinical involvement) in nails as 16.7%.

CONCLUSIONS

The effectiveness of lasers as a therapeutic intervention for dermatophyte toenail onychomycosis is limited based on complete, mycologic, and clinical cure rates. However, it may be possible to use different treatment parameters or lasers with a different wavelength to increase the efficacy. Lasers could be a potential management option for older patients and onychomycosis patients with coexisting conditions such as diabetes, liver, and/or kidney diseases for whom systemic antifungal agents are contraindicated or have failed.

Printing Drugs onto Nails for Effective Treatment of Onychomycosis

Inkjet printing (IJP) is an emerging technology for the precision dosing of medicines. We report, for the first time, the printing of the antifungal drug terbinafine hydrochloride directly onto nails for the treatment of onychomycosis. A commercial cosmetic nail printer was modified by removing the ink from the cartridge and replacing it with an in-house prepared drug-loaded ink. The drug-loaded ink was designed so that it was comparable to the commercial ink for key printability properties. Linear drug dosing was shown by changing the lightness of the colour selected for printing (R² = 0.977) and by printing multiple times (R² = 0.989). The drug loads were measured for heart (271 µg), world (205 µg) and football (133 µg) shapes. A disc diffusion assay against Trpytophan rubrum showed inhibition of fungal growth with printed-on discs. In vitro testing with human nails showed substantial inhibition with printed-on nails. Hence, this is the first study to demonstrate the ability of a nail printer for drug delivery, thereby confirming its potential for onychomycosis treatment.

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.

Effect of onychomycosis and treatment on patient-reported quality-of-life outcomes: A systematic review

BACKGROUND

Onychomycosis is the most common nail disorder, often causing physical, emotional, and aesthetic consequences. The effect of both the condition itself and treatment on quality of life has not been well studied.

OBJECTIVE

The objectives of this study were to systematically review the available literature describing the effect of onychomycosis and treatment on quality of life.

METHODS

We performed a search of the onychomycosis literature published before April 13, 2020. Articles were included in the review if primary data were presented, patient-reported outcome measures were used, and onychomycosis was specifically examined.

RESULTS

Thirty studies were included in the final analysis. Poorest quality-of-life scores were associated with women and fingernail involvement. Quality-of-life scores improved from baseline with all treatment types; there were greater improvements reported with oral treatments compared with topical ones.

CONCLUSIONS

This review affirms that onychomycosis significantly influences quality of life, warranting effective treatment. All treatments resulted in quality-of-life improvements; however, studies on oral and topical therapies were of higher quality than those evaluating devices. Increased efforts are needed to understand the effect of the disease and therapy as assessed by validated, nail-specific outcome measures that accurately assess patients' cosmetic, physical, and social difficulties.

Topical and device-based treatments for fungal infections of the toenails

BACKGROUND

Onychomycosis refers to fungal infections of the nail apparatus that may cause pain, discomfort, and disfigurement. This is an update of a Cochrane Review published in 2007; a substantial amount of new research warrants a review exclusively on toenails.

OBJECTIVES

To assess the clinical and mycological effects of topical drugs and device-based therapies for toenail onychomycosis.

SEARCH METHODS

We searched the following databases up to May 2019: the Cochrane Skin Group Specialised Register, CENTRAL, MEDLINE, Embase and LILACS. We also searched five trials registers, and checked the reference lists of included and excluded studies for further references to relevant randomised controlled trials.

SELECTION CRITERIA

Randomised controlled trials of topical and device-based therapies for onychomycosis in participants with toenail onychomycosis, confirmed by positive cultures, direct microscopy, or histological nail examination. Eligible comparators were placebo, vehicle, no treatment, or an active topical or device-based treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Primary outcomes were complete cure rate (normal-looking nail plus fungus elimination, determined with laboratory methods) and number of participants reporting treatment-related adverse events.

MAIN RESULTS

We included 56 studies (12,501 participants, average age: 27 to 68 years), with mainly mild-to-moderate onychomycosis without matrix involvement (where reported). Participants had more than one toenail affected. Most studies lasted 48 to 52 weeks; 23% reported disease duration (variable). Thirty-five studies specifically examined dermatophyte-caused onychomycosis. Forty-three studies were carried out in outpatient settings. Most studies assessed topical treatments, 9% devices, and 11% both. We rated three studies at low risk of bias across all domains. The most common high-risk domain was performance bias. We present results for key comparisons, where treatment duration was 36 or 48 weeks, and clinical outcomes were measured at 40 to 52 weeks. Based on two studies (460 participants), compared with vehicle, ciclopirox 8% lacquer may be more effective in achieving complete cure (risk ratio (RR) 9.29, 95% confidence interval (CI) 1.72 to 50.14; low-quality evidence) and is probably more effective in achieving mycological cure (RR 3.15, 95% CI 1.93 to 5.12; moderate-quality evidence). Ciclopirox lacquer may lead to increased adverse events, commonly application reactions, rashes, and nail alteration (e.g. colour, shape). However, the 95% CI indicates that ciclopirox lacquer may actually make little or no difference (RR 1.61, 95% CI 0.89 to 2.92; low-quality evidence). Efinaconazole 10% solution is more effective than vehicle in achieving complete cure (RR 3.54, 95% CI 2.24 to 5.60; 3 studies, 1716 participants) and clinical cure (RR 3.07, 95% CI 2.08 to 4.53; 2 studies, 1655 participants) (both high-quality evidence) and is probably more effective in achieving mycological cure (RR 2.31, 95% CI 1.08 to 4.94; 3 studies, 1716 participants; moderate-quality evidence). Risk of adverse events (such as dermatitis and vesicles) was slightly higher with efinaconazole (RR 1.10, 95% CI 1.01 to 1.20; 3 studies, 1701 participants; high-quality evidence). No other key comparison measured clinical cure. Based on two studies, compared with vehicle, tavaborole 5% solution is probably more effective in achieving complete cure (RR 7.40, 95% CI 2.71 to 20.24; 1198 participants), but probably has a higher risk of adverse events (application site reactions were most commonly reported) (RR 3.82, 95% CI 1.65 to 8.85; 1186 participants (both moderate-quality evidence)). Tavaborole improves mycological cure (RR 3.40, 95% CI 2.34 to 4.93; 1198 participants; high-quality evidence). Moderate-quality evidence from two studies (490 participants) indicates that P-3051 (ciclopirox 8% hydrolacquer) is probably more effective than the comparators ciclopirox 8% lacquer or amorolfine 5% in achieving complete cure (RR 2.43, 95% CI 1.32 to 4.48), but there is probably little or no difference between the treatments in achieving mycological cure (RR 1.08, 95% CI 0.85 to 1.37). We found no difference in the risk of adverse events (RR 0.60, 95% CI 0.19 to 1.92; 2 studies, 487 participants; low-quality evidence). The most common events were erythema, rash, and burning. Three studies (112 participants) compared 1064-nm Nd:YAG laser to no treatment or sham treatment. We are uncertain if there is a difference in adverse events (very low-quality evidence) (two studies; 85 participants). There may be little or no difference in mycological cure at 52 weeks (RR 1.04, 95% CI 0.59 to 1.85; 2 studies, 85 participants; low-quality evidence). Complete cure was not measured. One study (293 participants) compared luliconazole 5% solution to vehicle. We are uncertain whether luliconazole leads to higher rates of complete cure (very low-quality evidence). Low-quality evidence indicates there may be little or no difference in adverse events (RR 1.02, 95% CI 0.90 to 1.16) and there may be increased mycological cure with luliconazole; however, the 95% CI indicates that luliconazole may make little or no difference to mycological cure (RR 1.39, 95% CI 0.98 to 1.97). Commonly-reported adverse events were dry skin, paronychia, eczema, and hyperkeratosis, which improved or resolved post-treatment.

AUTHORS' CONCLUSIONS

Assessing complete cure, high-quality evidence supports the effectiveness of efinaconazole, moderate-quality evidence supports P-3051 (ciclopirox 8% hydrolacquer) and tavaborole, and low-quality evidence supports ciclopirox 8% lacquer. We are uncertain whether luliconazole 5% solution leads to complete cure (very low-quality evidence); this outcome was not measured by the 1064-nm Nd:YAG laser comparison. Although evidence supports topical treatments, complete cure rates with topical treatments are relatively low. We are uncertain if 1064-nm Nd:YAG laser increases adverse events compared with no treatment or sham treatment (very low-quality evidence). Low-quality evidence indicates that there is no difference in adverse events between P-3051 (ciclopirox hydrolacquer), luliconazole 5% solution, and their comparators. Ciclopirox 8% lacquer may increase adverse events (low-quality evidence). High- to moderate-quality evidence suggests increased adverse events with efinaconazole 10% solution or tavaborole 5% solution. We downgraded evidence for heterogeneity, lack of blinding, and small sample sizes. There is uncertainty about the effectiveness of device-based treatments, which were under-represented; 80% of studies assessed topical treatments, but we were unable to evaluate all of the currently relevant topical treatments. Future studies of topical and device-based therapies should be blinded, with patient-centred outcomes and an adequate sample size. They should specify the causative organism and directly compare treatments.

A Practical Guide to Curing Onychomycosis: How to Maximize Cure at the Patient, Organism, Treatment, and Environmental Level

Onychomycosis is a fungal nail infection caused by dermatophytes, non-dermatophyte molds, and yeasts. Treatment of this infection can be difficult, with relapse likely to occur within 2.5 years of cure. The objective of this article is to review factors that can impact cure and to suggest practical techniques that physicians can use to maximize cure rates. Co-morbidities, as well as disease severity and duration, are among the many patient factors that could influence the efficacy of antifungal therapies. Furthermore, organism, treatment, and environmental factors that may hinder cure include point mutations, biofilms, affinity for non-target enzymes, and exposure to fungal reservoirs. To address patient-related factors, physicians are encouraged to conduct confirmatory testing and treat co-morbidities such as tinea pedis early and completely. To combat organism-focused factors, it is recommended that disruption of biofilms is considered, and drugs with multiple routes of delivery and unique mechanisms of action are prescribed when traditional agents are not effective. Extending follow-up periods, using combination treatments, and considering pulse regimens may also be of benefit. Through these practical techniques, physicians can maximize cure and limit the risk of relapse and re-infection.

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.

2018 update on dermatologic laser therapy: Part 1 - epilation, vascular lesions and pigments

Technical advances in recent years have led to new dermatologic laser systems, light sources, and treatment concepts. Commonly used wavelengths - generated today with LED-based devices - allow for the combination of various tissue effects and are associated with improved outcomes. Laser hair removal has become more efficient with the use of diode lasers that emit multiple wavelengths simultaneously. In the near future, novel LED-based lasers will also be introduced for the treatment of vascular lesions. Here, too, the combination of different wavelengths promises to be beneficial. Picosecond lasers have led to advances in the field of pigment removal (tattoos).

Treatment of onychomycosis using a 1064-nm diode laser with or without topical antifungal therapy: a single-center, retrospective analysis in 56 patients

Background

Currently available treatment options for onychomycosis such as topical and systemic antifungals are often of limited efficacy, difficult to administer or associated with relevant side effects. Non-ablative laser therapy is proposed to represent a safe alternative without the disadvantages of drugs. Yet, to date, the efficacy of laser therapy for onychomycosis is discussed controversially. Against this background, we performed a systematic retrospective analysis of our clinical experience of 4 years of onychomycosis treatment applying a long-pulsed 1.064-nm diode laser.

Methods

We retrospectively evaluated the records of 56 patients with microscopic and culturally proven onychomycosis affecting a toenail of the hallux and other toes, who had been treated with a long-pulsed 1.064-nm diode laser (FOX, A.C.R. Laser GmbH, Nuremberg) during the time period of July 2013–December 2016 with or without concomitant topical antifungals. Thereof, 27 patients received laser treatment and 29 patients received laser treatment in combination with local antifungals. We conducted a mean of 3.9 laser treatments at 2–6-week intervals. The primary endpoint of our analysis was clinical improvement; secondary endpoints were complete remission of fungal pathogens in fungal culture and in microscopy.

Results

Clinical improvement was achieved in 56% of patients treated with laser only after a mean of 4.5 treatments and in 69% of patients treated with laser in combination with topical antifungals after a mean of 3.6 treatments. Cultural healing was detected in 63% of patients treated with laser only after a mean of 5.4 treatments, vs. 86% of patients treated with laser and concomitant topical antifungals after a mean of 4.8 treatments. Microscopic healing (complete healing) with the absence of fungal pathogens was achieved in 11% of patients after a mean of 4.7 treatments with laser only, vs. 21% of patients treated with laser and concomitant topical antifungals after a mean of 4 treatments. No relevant adverse effects were observed.

Conclusions

The 1.064-nm diode laser is an effective and safe option for the treatment of onychomycosis. Of note, the combination with topical antifungals will increase overall treatment efficacy and reduce the time to healing. Particularly, patients with contraindications against systemic antifungals may benefit from this multimodal therapeutic approach. Our data, moreover, suggest that treatment efficacy is positively correlated with the total number of laser treatments.

A practical application of onychomycosis cure - combining patient, physician and regulatory body perspectives

Due to the high relapse rates and the rise of predisposing factors, the need for curing onychomycosis is paramount. To effectively address onychomycosis, the definition of cure used in a clinical setting should be agreed upon and applied homogeneously across therapies (e.g. oral, topical and laser treatments). In order to determine what is or what should be used to define cure in a clinical setting, a literature search was conducted to identify methods used to evaluate treatment success. The limitations, strengths, prevalence and utility of each outcome measure were investigated. Seven ways to measure treatment success were identified; mycological cure, patient/investigator assessments, complete cure, quality of life instruments, severity indexes, clinical cure and temporary clearance. Despite its shortcomings, mycological cure is the most objective and consistent outcome measure used across onychomycosis studies. It is suggested that diagnostic goals of onychomycosis should be used to define cure in a clinical setting. Modifications to outcome measures such as incorporating molecular-based techniques could be a future avenue to explore.

Challenges and Opportunities in the Management of Onychomycosis

Onychomycosis is an increasingly common fungal nail infection, chiefly caused by dermatophyte fungi. The disease is notoriously difficult to treat due to the deep-seated nature of fungi within the nail plate, prolonged treatment requirements, poor patient adherence and frequent recurrences. Given the poor efficacy of currently available topical and systemic therapies, there is a renewed interest in exploring alternative treatment modalities for onychomycosis. Natural therapies, physical treatments and various combination therapies have all shown potential for the management of onychomycosis, though research on many of these methods is still in preliminary stages. Further large, well-designed, randomised controlled trials are necessary to confirm the efficacy of these novel treatments in order to make formal recommendations regarding their use in the management of onychomycosis.

Onychomycosis: Treatment and prevention of recurrence

Onychomycosis is a fungal nail infection caused by dermatophytes, nondermatophytes, and yeast, and is the most common nail disorder seen in clinical practice. It is an important problem because it may cause local pain, paresthesias, difficulties performing activities of daily living, and impair social interactions. The epidemiology, risk factors, and clinical presentation and diagnosis of onychomycosis were discussed in the first article in this continuing medical education series. In this article, we review the prognosis and response to onychomycosis treatment, medications for onychomycosis that have been approved by the US Food and Drug Administration, and off-label therapies and devices. Methods to prevent onychomycosis recurrences and emerging therapies are also described.

Light as a Broad-Spectrum Antimicrobial

Antimicrobial resistance is a significant and growing concern. To continue to treat even simple infections, there is a pressing need for new alternative and complementary approaches to antimicrobial therapy. One possible addition to the current range of treatments is the use of narrow-wavelength light as an antimicrobial, which has been shown to eliminate a range of common pathogens. Much progress has already been made with blue light but the potential of other regions of the electromagnetic spectrum is largely unexplored. In order that the approach can be fully and most effectively realized, further research is also required into the effects of energy dose, the harmful and beneficial impacts of light on eukaryotic tissues, and the role of oxygen in eliciting microbial toxicity. These and other topics are discussed within this perspective.

Case Report of Onychomycosis and Tinea Corporis Due to Microsporum gypseum

Background:

Microsporum gypseum is a geophilic dermatophyte that colonises keratinous substances in the soil. Fur-bearing animals carry this dermatophyte but are rarely infected. Human infection can be acquired from the soil, carrier or infected animals, and rarely other humans. M gypseum is an uncommon cause of cutaneous infection in humans and typically manifests as tinea corporis, tinea barbae, and tinea capitis. Onychomycosis is rarely caused by M gypseum.

Case Summary:

We present a case of a 32-year-old white man who presented with a red scaly rash and nail dystrophy after adopting a pet rat 10 years prior to presentation. A fungal culture of a nail clipping grew out M gypseum, and the patient was treated with terbinafine daily for 6 weeks for dystrophic onychomycosis and tinea corporis. After the 6 weeks of treatment, the erythema at the proximal nail fold and distal finger had improved but still persisted. An additional 6 weeks of terbinafine daily completely resolved the clinical manifestations of onychomycosis.

Conclusion:

The increase in incidence of M gypseum onychomycosis over the past 2 decades is thought to be due to phylogenetic evolution of the dermatophyte from soil saprophyte to a human parasite. Increasing domestication of mammals is also thought to contribute to increasing incidence. Treatment consists of an extended course of terbinafine or itraconazole.

Treatment of Dermatophytosis in Elderly, Children, and Pregnant Women

Dermatophytic infection of the skin and its appendages is a common occurrence. Though usually straightforward, treatment of dermatophytosis becomes notably challenging in certain population groups - pregnant women, children, and elderly. Treatment with topical azoles/allylamines alone is effective in limited cutaneous disease in all three groups. Terbinafine is the preferred oral agent in elderly population for treatment of extensive cutaneous disease and onychomycosis due to its lack of cardiac complications and lower propensity for drug interactions. If required, additional physical/mechanical modalities can be employed for symptomatic onychomycosis. Data for systemic therapy in children mainly pertains to the treatment of tinea capitis. At present, very little data exists regarding the safety of systemic antifungals in pregnancy and there is an effort to restrict treatment to topical therapies because of their negligible systemic absorption.