Once Weekly Application of Urea 40% and Bifonazole 1% Leads to Earlier Nail Removal in Onychomycosis

Introduction

Onychomycosis is a chronic nail fungal infection resulting in nail damage and a decreased quality of life. Chemical avulsion of the nail with urea and bifonazole -removes fungally infected debris, increasing antifungal treatment efficacy and penetration. Previous clinical ob-servations describe patients who applied their urea and -bifonazole ointment less frequently, achieving earlier nail removal. In this study, we analyzed the relationship between duration of urea and bifonazole application and time to nail avulsion.

Methods

χ² tests, multiple regression analysis, and ANOVA were performed to analyze the similarities between treatment regimens (daily, every 3 days, or once a week), association of regimens or patient characteristics to nail removal, and compare time to nail removal between each regimen, respectively.

Results

Daily application of ointment and sealing resulted in an average length of time (±SD) to nail removal of 18.7 days (±6.8 days); once every 3 days resulted in nail removal at 12.7 days (±6.2 days) and once per week at 11 days (±4.46 days) (p < 0.001). Age was the only patient factor that affected duration to nail removal.

Conclusion

Once weekly application of ointment with sealing for a 1-week duration is associated with a decrease in time to complete chemical avulsion of the nail by approximately 1 week.

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.

In vivo antifungal activity of dipyrithione against Trichophyton rubrum on guinea pig dermatophytosis models

The treatment of dermatophytosis has improved considerably over the past several decades following the introduction of the oral antifungals such as azoles and amphotericin B. However, these drugs have had limited success because the treated fungi often develop drug resistance, resulting in recurrence when applied in various topical formulations. Thus, there are constant needs for new topical agents that are effective against dermatophytosis. Dipyrithione is an attractive candidate to become an antifungal agent due to its broad spectrum of antimicrobial activities. In this study, we determined that dipyrithione could potently inhibit the growth of Trichophyton rubrum, which is the most common cause of dermatophytosis. The MIC₅₀ value of dipyrithione against T. rubrum was measured as 6.03 μM, as compared with miconazole (MIC₅₀: 1.38 μM). Additionally, the compound caused morphological changes in the fungi, which was examined using the morphological interference assay. The in vivo experiment further revealed that dipyrithione had a healing effect on the skin of guinea pigs infected with T. rubrum. Our studies have demonstrated that dipyrithione had a potent antifungal activity in vitro and in vivo, suggesting that it could be formulated as a potential antifungal lead compound in search for novel therapeutic agents against dermatophytosis.

Chemical and physical strategies in onychomycosis topical treatment: A review

Onychomycosis is a fungal infection of the fingernails or toenails caused by dermatophytes, nondermatophytes, moulds, and yeasts. This condition affects around 10-30% people worldwide, negatively influencing patients' quality of life, with severe outcomes in some cases. Since the nail unit acts as a barrier to exogenous substances, its physiological features hampers drug penetration, turning the onychomycosis treatment a challenge. Currently, there are several oral and topical therapies available; nevertheless, cure rates are still low and relapse rates achieves 10-53%. Also, serious side effects may be developed due to long-term treatment. In light of these facts, researchers have focused on improving topical treatments, either by modifying the vehicle or by using some physical technique to improve drug delivery trough the nail plate, hence increasing therapy effectiveness. Therefore, the aim of this paper is to explain these novel alternative approaches. First, the challenges for drug ungual penetration are presented. Then, the chemical and physical strategies developed for overcoming the barriers for drug penetration are discussed. We hope that the information gathered may be useful for the development of safer and more effective treatments for onychomycosis.

Antifungal activity of isothiocyanates extracted from horseradish (Armoracia rusticana) root against pathogenic dermal fungi

To develop natural antifungal agents against pathogenic dermal fungi, the antifungal activity of isothiocyanates (ITCs) extracted from horseradish (Armoracia rusticana) root was investigated. A paper disk diffusion assay showed that ITCs inhibited growth of the four pathogenic dermal fungi (Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis, and Epidermophyton floccosum) at 5000 μg/mL, as well as perfectly inhibited the growth of the fungi at 10,000 μg/mL in a concentration-dependent manner. The minimum inhibitory concentrations of ITCs against T. rubrum, T. mentagrophytes, M. canis, and E. floccosum were 200, 200, 100, and 100 μg/mL, respectively. The minimum fungicidal concentrations of ITCs against the four pathogenic dermal fungi were 200 μg/mL. These results strongly suggested that ITCs extracted from horseradish root can be a candidate of natural antifungal agents against pathogenic dermal fungi, even though further study is needed to investigate how to use ITCs in clinical therapy.

Onychomycosis: Evaluation, Treatment Options, Managing Recurrence, and Patient Outcomes

Onychomycosis is the most common nail disease seen in podiatric practice. Effective long-term management remains problematic. We need to treat onychomycosis effectively to prevent its progression into a severe, debilitating, and painful condition, and to manage recurrence. With new agents now available and greater discussion on management strategies, this article reviews the appropriate evaluation of the disease, treatment options, and optimal patient outcomes.

Randomized, double-blind, comparative study on efficacy and safety of itraconazole pulse therapy and terbinafine pulse therapy on nondermatophyte mold onychomycosis: A study with 90 patients

BACKGROUND

Nondermatophyte mold (NDM) onychomycosis shows poor response to current topical, oral or device-related antifungal therapies. This study was aimed to determine the efficacy and safety of itraconazole and terbinafine pulse therapy on NDM onychomycosis.

METHODS

Mycologically proven subjects were treated with itraconazole 400 mg daily or terbinafine 500 mg daily for 7 days/month; two pulses for fingernails and three pulses for toenails(SLCTR/2013/013).

RESULTS

One-hundred seventy-eight patients underwent mycological studies and 148 had positive fungal isolates. NDM were the prevailing fungi, 68.2%, followed by candida species 21.6%, and dermatophytes made up only 10.1%. Out of NDM Aspergillus spp (75.1%) predominated followed by 8.9% Fusarium spp and 4.95% Penicillium spp. The clinical cure at completion of pulse therapy was statistically significant 9.2% versus 2.0% (p < 0.05) in itraconazole group. But no statistically significant difference was detected between the two regimens at the end of 12 months; 65.1% versus 54.64%. Recurrences observed in both groups (6.5% vs. 4.1%) were not statistically significant. With itraconazole pulse 68.22% Aspergillus spp, 50.0% Fusarium spp and 84.6% Penicillium spp showed clinical cure, while terbinafine pulse cured 55.0% Aspergillus spp and 50.0% Fusarium spp.

CONCLUSIONS

NDM was the prevailing fungi in onychomycosis in Sri Lanka. Both itraconazole and terbinafine were partially effective on NDM onychomycosis showing a clinical cure of 54-65%. Future research should focus on searching more effective antifungal for NDM onychomycosis.

Comparative Sensitivity of Trichophyton and Aspergillus Conidia to Inactivation by Violet-Blue Light Exposure

OBJECTIVE

To investigate the use of 405 nm light for inhibiting the growth of selected species of dermatophytic and saprophytic fungi.

BACKGROUND DATA

The increasing incidence and resilience of dermatophytic fungal infections is a major issue, and alternative treatment methods are being sought.

METHODS

The sensitivity of the dermatophytic fungi Trichophyton rubrum and Trichophyton mentagrophytes to 405 nm violet-blue light exposure was investigated, and the results compared with those obtained with the saprophytic fungus Aspergillus niger. Microconidia of T. rubrum and T. mentagrophytes and conidia of A. niger were seeded onto Sabauroud dextrose agar plates and irradiated with 405 nm light from an indium-gallium-nitride 99-DIE light-emitting diode (LED) array and the extent of inhibition was measured.

RESULTS

Germination of the microconidia of the Trichophyton species was completely inhibited using an irradiance of 35 mW/cm(2) for 4 h (dose of 504 J/cm(2)). A. niger conidia showed greater resistance, and colonial growth developed after light exposure. In liquid suspension tests, 405 nm light dose levels of 360, 720, and 1440 J/cm(2) resulted in complete inactivation of T. rubrum microconidia, whereas A. niger showed greater resistance, and at the highest dose level applied (1440 J/cm(2)) although A niger hyphae were completely inactivated, only a 3-log10 reduction of a 5-log10 conidial suspension was achieved.

CONCLUSIONS

The study results demonstrate the relatively high sensitivity of Trichophyton microconidia to 405 nm violet-blue light, and this is may be of potential interest regarding the control and treatment of dermatophyte infections.

Infected nail plate model made of human hair keratin for evaluating the efficacy of different topical antifungal formulations against Trichophyton rubrum in vitro

A novel model of infected nail plate for testing the efficacy of topical antifungal formulations has been developed. This model utilized keratin film made of human hair keratin as a nail plate model. Subsequent to infection by Trichophyton rubrum, the common causative agent of onychomycosis, keratin films as infected nail plate models were treated with selected topical formulations, that is cream, gel, and nail lacquer. Bovine hoof was compared to keratin film. In contrast to the common antifungal susceptibility test, the antifungal drugs tested were applied as ready-to-use formulations because the vehicle may modify and control the drug action both in vitro and in vivo. Extrapolating the potency of an antifungal drug from an in vitro susceptibility test only would not be representative of the in vivo situation since these drugs are applied as ready-to-use formulations, for example as a nail lacquer. Although terbinafine has been acknowledged to be the most effective antifungal agent against T. rubrum, its antifungal efficacy was improved by its incorporation into an optimal formulation. Different gels proved superior to cream. Therefore, this study is able to discriminate between efficacies of different topical antifungal formulations based on their activities against T. rubrum.

Efficacy, safety and tolerability of topical terbinafine nail solution in patients with mild-to-moderate toenail onychomycosis: results from three randomized studies using double-blind vehicle-controlled and open-label active-controlled designs

BACKGROUND

Terbinafine nail solution (TNS) was developed for the treatment of onychomycosis.

OBJECTIVE

To assess the efficacy of TNS vs. vehicle and amorolfine 5% nail lacquer.

METHODS

Subjects with mild-to-moderate toe onychomycosis (25% to ≤75% nail-involvement, matrix uninvolved) were randomized to receive either TNS or vehicle in two double-blind studies, and to TNS or amorolfine in an active-controlled, open-label study. Primary endpoint was complete cure (no residual clinical involvement and negative mycology) at week 52. Secondary endpoints were mycological cure (negative mycology defined as negative KOH microscopy and negative culture) and clinical effectiveness (≤10% residual-involvement and negative mycology) at week 52.

RESULTS

Complete cure was not different between TNS vs. vehicle and amorolfine. Mycological cure was higher with TNS vs. vehicle, as was clinical effectiveness with TNS vs. vehicle, and TNS and amorolfine were not different for secondary efficacy endpoints. Patients achieving mycological cure had a better clinical outcome, and efficacy was improved in subjects with milder disease. Post hoc analysis suggests that nail thickness is an important prognostic factor. Moreover, mycological cure may require 6 months of treatment regimen while complete cure and clinical effectiveness may be achievable only after 10 months. A simulation study suggests that longer treatment duration would have resulted in higher complete cure with TNS vs. vehicle. Study treatments were well-tolerated.

CONCLUSION

Primary efficacy objectives were not met in the studies reported herein. Possible reasons for failure to achieve significant outcomes include insufficient length of treatment; stringency of primary endpoint and severity of nail involvement of study population.

What is a combination treatment and how it may be used in onychomycosis

Combination treatment of onychomycosis is based on supplementation of systemic antifungal therapy with different topical techniques, which now include antifungal nail lacquers. Controversies in establishing potential and efficacy of combination treatment in onychomycosis may be overcome by rational administration of any treatment modality after careful evaluation of both the disease and the patient. Application of antifungal nail varnishes such as 8% ciclopirox offers several benefits in treating onychomycosis. With improved efficacy and safety, onychomycosis combination therapy appears to be less expensive and more reliable in terms of reduced rates of relapse and re-infection. Russian and international clinical trials and studies with ciclopirox nail lacquer have revealed the indications and proved the high effectiveness of certain algorithms of combination treatment.

Topical Treatment of Dermatophytic Lesion on Mice (Mus musculus) Model

Antidermatophytic potential of three weed plants viz. Tridax procumbens L., Capparis decidua (forsk) Edgew and Lantana camara L. were explored and experimentally induced dermatophytic lesion was topically treated in mice. Microbroth dilution method was carried out for determination of MIC and MFC of different extracts of selected plants. In animal studies, mice were experimentally inoculated with Trichophyton mentagrophytes and infected animals were topically treated with 5 mg/g terbinafine and two concentrations, i.e., 5 and 10 mg/g of test extract ointment. Complete recovery from the infection was observed on 12th day of treatment for reference drug terbinafine (5 mg/g) and 10 mg/g concentration of test extract ointment whereas 5 mg/g concentration of test extract ointment showed complete cure on 16th day of treatment. Fungal burden was also calculated by culturing skin scrapings from infected animals of different groups. Test extract ointment successfully treated induced dermatophytosis in mice without any disease recurrence incidences, thereby indicating efficacy of test extract as an excellent topical antifungal agent for the cure of dermatophytosis.

[Antifungal agents for onychomycoses]

Nail fungal infections are considered one of the major dermatological problems due to their high rate of therapeutic failure, management and treatment difficulties. Long-term treatments, inadequate therapies, mycological misdiagnosis and follow-up, secondary alterations of the nail, and resistant microorganisms, are some of the causes of these complications. Although the discovery of new antifungal agents has provided some effective molecules, none of the current available drugs are totally effective. It is important to continue researching in this field to provide new antifungal agents and combined therapies.

Hydrosoluble medicated nail lacquers: in vitro drug permeation and corresponding antimycotic activity

BACKGROUND

Two nail lacquers, containing ciclopirox (CPX) or amorolfine (MRF), based on water-insoluble polymers are currently considered mainstays of topical treatment of onychomycosis. The present study aimed at evaluating the antimycotic activity of a new water-soluble nail lacquer containing CPX (CPX/sol), easily removable by washing with water and applicable to periungual skin.

OBJECTIVES

To compare transungual permeation of CPX with that of MRF in the same hydroxypropyl chitosan-based nail lacquer (MRF/sol) and with a nonwater-soluble reference (Loceryl); Galderma International, La Défense, France), and to evaluate the antimycotic activity of CPX/sol and Loceryl against the most common fungal strains that cause onychomycosis. Methods In vitro drug permeation experiments with CPX/sol, MRF/sol and Loceryl were carried out through bovine hoof slices. Experimental permeates from CPX/sol and Loceryl underwent in vitro susceptibility testing against clinical isolates of dermatophytes, moulds and yeast. Results MRF transungual flux from MRF/sol lacquer was significantly higher when compared with Loceryl. CPX was able to permeate hoof membranes more easily compared with MRF. CPX and MRF concentrations in the subungual fluids collected after application of CPX/sol or Loceryl were sufficient to inhibit fungal growth, with the exception of Candida parapsilosis. Smaller amounts of fluid containing CPX were required for complete inhibition of fungal growth. Efficacy index values were significantly higher for CPX/sol. Conclusions Application of the CPX/sol nail lacquer allows rapid nail penetration of CPX, providing CPX levels sufficient to inhibit fungal growth for a prolonged period of time (30 h) after application of lacquer dose. CPX/sol nail lacquer appeared superior to the market reference Loceryl in terms of both vehicle (hydroxypropyl chitosan) and active ingredient (CPX) as witnessed by its higher efficacy on all nail pathogens.

Antifungal Activity of Eugenia umbelliflora against Dermatophytes

Antifungal activities of Eugenia umbelliflora Berg. (Myrtaceae) were tested in vitro against a panel of standard and clinical isolates of human fungal pathogens (dermatophytes and opportunistic saprobes). Methanol extracts of leaves and fruits of E. umbelliflora were separately prepared and partitioned, to yield dichloromethane (DCM), ethyl acetate (EtOAc) and aqueous fractions (Aq). Three compounds (1-3) were obtained from the DCM extract using chromatographic procedures. Antifungal assays were performed using agar dilution techniques. Both extracts (fruits and leaves), their DCM and EtOAc fractions, and compound 2 (betulin and betulinic acid) presented selective antifungal activity against dermatophytes (Epidermophyton floccosum, Microsporum canis, Microsporum gypseum, Trichophyton rubrum, Trichophyton mentagrophytes), with MIC values between 200 and 1000 μg/mL, and interestingly, inhibited 4/5 species with MIC values of ≤500 ≤g/mL. The aqueous fractions of fruits and leaves, and compounds 1 (α, β amyrin) and 3 (taraxerol) were inactive up to the maximum concentrations tested (1000 μg/mL).

Onychomycosis: diagnosis and definition of cure

Until now, there has been no agreement on criteria defining resolution of onychomycosis. Most published reports use clinical and mycological cure, which comprises a completely normal-appearing nail plate, and negative nail culture and microscopy results, as the end point for defining success of therapeutic intervention. Reported here is the definition of onychomycosis, which delineates both primary and secondary criteria for diagnosis of onychomycosis and identifies clinical and laboratory parameters to define a resolved fungal nail infection. Onychomycosis cure is defined by the absence of clinical signs or the presence of negative nail culture and/or microscopy results with one or more of the following minor clinical signs: (1) minimal distal subungual hyperkeratosis; and (2) nail-plate thickening. Clinical signs indicative of persistent onychomycosis at the end of the observation period include (1) white/yellow or orange/brown streaks or patches in or beneath the nail plate; and (2) lateral onycholysis with subungual debris. Although nail appearance will usually continue to improve after cessation of therapy, the nails may have a persistent abnormal appearance even in cases where treatment has been effective.

Analysis of the dermatophyte Trichophyton rubrum expressed sequence tags

Background

Dermatophytes are the primary causative agent of dermatophytoses, a disease that affects billions of individuals worldwide. Trichophyton rubrum is the most common of the superficial fungi. Although T. rubrum is a recognized pathogen for humans, little is known about how its transcriptional pattern is related to development of the fungus and establishment of disease. It is therefore necessary to identify genes whose expression is relevant to growth, metabolism and virulence of T. rubrum.

Results

We generated 10 cDNA libraries covering nearly the entire growth phase and used them to isolate 11,085 unique expressed sequence tags (ESTs), including 3,816 contigs and 7,269 singletons. Comparisons with the GenBank non-redundant (NR) protein database revealed putative functions or matched homologs from other organisms for 7,764 (70%) of the ESTs. The remaining 3,321 (30%) of ESTs were only weakly similar or not similar to known sequences, suggesting that these ESTs represent novel genes.

Conclusion

The present data provide a comprehensive view of fungal physiological processes including metabolism, sexual and asexual growth cycles, signal transduction and pathogenic mechanisms.

In vitro antifungal oral drug and drug-combination activity against onychomycosis causative dermatophytes

We present the results of studies of the in vitro susceptibility of 52 isolates of Trichophyton rubrum and 40 of Trichophyton mentagrophytes to griseofulvin, terbinafine, itraconazole, ketoconazole, fluconazole and cyclopiroxolamine. All test strains were recovered from patients with toe nail onychomycosis and the minimum inhibitory concentration (MIC) of each antifungal against both species was individually assessed. In addition, we investigated the MIC of the combination of cyclopiroxolamine and itraconazole and cyclopiroxolamine and ketoconazole. The NCCLS approved procedure M38-A as modified by Santos and Hamdan was employed. The studies of the two drug combinations were conducted with a checkerboard design. Analysis of the data revealed that terbinafine was the most effective in vitro against all isolates, followed in order by itraconazole, cyclopiroxolamine, ketoconazole and fluconazole. We observed no significant difference in the in vitro susceptibility profiles between either species to any of the antifungals (P<0.05). Our in vitro results confirm that terbinafine is the most effective of the antifungals included in this study. Furthermore, synergistic interactions were found in the two drug combinations with all of the dermatophyte test isolates. The latter results are in agreement with clinical data that show synergism between oral and topical antifungals in the treatment of onychomycosis.

Onychomycosis Therapies: Strategies to Improve Efficacy

The combination of relatively high treatment failure rates and infection relapse rates warrants consideration of ways in which antifungal therapy can be delivered so that efficacy rates can be improved. These involve the combination of available therapies and/or a modification of treatment regimens.

Literature review. Onychomycosis

Onychomycoses have been divided into several categories depending on the site of nail penetration by the fungus. However, not all cases entirely fit with this classification, such as potentially the deep spread of superficial fungi, suggesting alternative penetration routes. A recent European study showed that the prevalence of onychomycosis may be as high as 26.9%. The main causative agent varies according to climate; dermatophyte infections are common worldwide (70% in Europe). Mycological examination is currently the preferred diagnostic method, despite a false-negative rate of 30%. A clinical diagnostic aid that can be used alongside mycological tests is currently being developed. Newer diagnostic approaches include calcofluor, which stains fungi in nails, and molecular genetic techniques for species recognition (e.g. RFLP). Restriction fragment length polymorphism (RFLP) can also distinguish between failed treatment and reinfection. Onychomycosis can be treated with numerous oral and topical agents alone or in combination. In some studies, combination therapy appears more effective than monotherapy.

In vitro transungual permeation of ciclopirox from a hydroxypropyl chitosan-based, water-soluble nail lacquer

Commercial antimycotic nail lacquers are commonly based on water-insoluble resins. The present study was aimed at evaluating a novel, experimental nail lacquer (P-3051, Polichem SA, Lugano, Switzerland) based on the water-soluble film-forming agent hydroxypropyl chitosan (HPCH). The in vitro permeation of ciclopirox (CPX) from P-3051 and from a commercial, water-insoluble lacquer based on a vinyl resin (Penlac, Aventis Pharma), was investigated using thin membranes obtained from bovine hooves, an accepted model for human nails. Similar CPX permeation fluxes at steady state through the membranes, but significantly different lag times were observed for P-3051 and Penlac, when these were tested as dry films. The formulations thus appeared to influence only the time required by CPX to saturate the membrane, and not the final drug concentration gradient in the membrane. Permeation experiments performed on the same membranes and on hairless mouse skin with P-3051 and with a similar, HPCH-free vehicle (ERV), both tested in liquid form, disproved the possibility that HPCH might act as a permeation enhancer for CPX in either substrate. The possible reasons for the greater efficiency of the HPCH vehicle in terms of CPX transfer from the vehicle itself to the keratin membrane are discussed. This effect might be tentatively attributed to a particular affinity of HPCH for the membrane, resulting in intimate contact and strong adhesion of the HPCH lacquer to the keratin substrate.

Skin infections and ageing

Elderly individuals have an increased susceptibility to skin infections due to age-related anatomical, physiological and environmental factors. The types of organisms that cause primary skin and soft tissue infections are diverse, and include bacterial, viral and fungal pathogens as well as parasites. In the elderly, these infections and infestations may present with atypical signs and symptoms or may complicate underlying chronic skin disorders. Clinical features, investigations and management of the following important and common skin infections are described in more detail: cellulitis, erysipelas, necrotizing fasciitis, impetigo, folliculitis, furunculosis and carbunculosis, erythrasma, herpes zoster and postherpetic neuralgia, herpes simplex, warts, molluscum contagiosum, dermatophytosis of the skin, hair and nails, candidiasis, and scabies. Treatment should be based on the results of the appropriate diagnostic tests. Correct diagnosis and therapy of skin infections lead to satisfactory outcome in the majority of elderly patients.

Assessing treatment outcomes in toenail onychomycosis clinical trials

Several oral and topical medications are available for the treatment of onychomycosis, a widespread fungal infection of the nail. Since efficacy criteria vary greatly among clinical trials for onychomycosis treatment, it is difficult for physicians to compare outcomes and determine the appropriate therapy for a given patient. The present analysis evaluates the efficacy criteria used in intention-to-treat clinical trials of itraconazole, terbinafine, and 8% ciclopirox nail lacquer, drugs approved by the US FDA for the treatment of onychomycosis. Efficacy parameters often appear to use subjective assessment tools and may not include the actual size measurement of the affected target nail as an efficacy variable. Parameters, which assess both mycologic and clinical cure, are frequently omitted from clinical trials. Not surprisingly, clinical trials with stringent efficacy criteria, which assess both mycologic and clinical response/cure without use of subjective methods, appear to have the lowest rates for both therapeutic response and complete cure. Thus, an evaluation of treatment options for onychomycosis cannot solely compare success/failure rates in clinical trials, but requires a critical appraisal of the efficacy criteria utilized in those trials.

Drug synergies and the potential for combination therapy in onychomycosis

Synergy between antifungal drugs is well recognized. However, combinations of antifungals are yet to be widely adopted to treat onychomycosis. The rationale for the combination of topical and oral therapy in the treatment of onychomycosis is that the systemic antifungal reaches the infection area via the nail bed and the topical agent is absorbed through the nail surface. The combination of antifungals used should ideally be synergistic in their mode of action. Synergy between amorolfine and other antifungals has been demonstrated in vitro. This is presumably due to differences in the precise point of action of the drugs on the fungal cell membrane, where they inhibit the synthesis of ergosterol. Thus, combinations can result in increased antifungal activity at lower concentrations of both drugs. The potential exists therefore for combinations of antifungals to achieve higher cure rates in onychomycosis, in a shorter time than is currently possible. This approach warrants further investigation.

Superficial fungal infections: an update on pityriasis versicolor, seborrheic dermatitis, tinea capitis, and onychomycosis

The recent advances in pityriasis versicolor, seborrheic dermatitis, tinea capitis and onychomycosis are reviewed. Some highlighted points include the new classification of Malassezia species, and the association of Malassezia species with seborrheic dermatitis. The use of terbinafine, fluconazole, and itraconazole for the treatment of tinea capitis is discussed. The management of onychomycosis, highlighting the high efficacy rates obtained with terbinafine when used to treat dermatophyte toenail onychomycosis, is discussed. The use of combination therapies in some circumstances to maximize cure rates is reviewed.

How to improve cure rates for the management of onychomycosis

To improve the treatment of onychomycosis clinicians need to identify correctly the causative organism, choose a therapy that is effective against the pathogen, and take into consideration the pharmacokinetics (eg, bioavailability, drug interactions) of the oral agent. In addition, variations of the standard regimens may need to be considered (ie, booster or supplemental therapy). To reduce the recurrence of onychomycosis, once mycologic cure has been achieved, clinicians should educate their patients about proper foot care. Familiarity with the symptoms and signs of tinea pedis and onychomycosis may enable patients to seek appropriate care when the disease is at an early stage.