The prevalence of onychomycosis in Finland

Pediatric dermatophyte onychomycosis: a review

Recent studies have reported an increase in pediatric onychomycosis prevalence worldwide, suggesting that this population may be increasingly affected by the infection. A summary of the epidemiological impact, antifungal treatment options, special considerations for at-risk subpopulations, and methods to prevent infection and recurrence are discussed. A systematic review of available epidemiological studies found the worldwide prevalence of culture-confirmed pediatric toenail onychomycosis to be 0.33%, with no significant increases in prevalence over time. A systematic review of studies investigating the efficacy of various antifungals in treating pediatric onychomycosis found high cure rates and low frequency of adverse events with systemic itraconazole and terbinafine; however, the studies are few, dated, and lack impact because of small sample sizes. Comparatively, clinical trials implementing FDA-approved topical antifungal treatments report slightly reduced cure rates with larger sample sizes. Patients with immunity-altering conditions, such as Down's syndrome, or those immunosuppressed because of chemotherapy or HIV/AIDS are at a greater risk of onychomycosis infection and require special consideration with treatment. Proper sanitization and hygiene practices are necessary to reduce the risk of acquiring infection. Early diagnosis and treatment of onychomycosis in children, as well as any affected close contacts, are crucial in reducing the impact of the disease.

Antidermatophyte activity and PK/PD of ME1111 in a guinea pig model of tinea corporis

Onychomycosis, a superficial fungal infection of the nails, is prevalent in many areas of the world. Topical agents for onychomycosis need to reach the subungual layer and nail bed to exert antifungal activity in the presence of keratin, the major component of the nail. It is difficult to evaluate the efficacy and pharmacodynamics of topical agents for onychomycosis in a non-clinical evaluation system. No consistent animal model has yet been established to predict the efficacy of topical agents for onychomycosis. In this study, we evaluated the pharmacokinetics and pharmacodynamics of ME1111 in a guinea pig model of tinea corporis designed to predict the efficacy of topical medication for onychomycosis in the vicinity of the nail bed. Trichophyton mentagrophytes TIMM1189 was infected on the back skin of guinea pigs, and ME1111 solution (5%, 10%, or 15%) was administered topically, once daily for 14 consecutive days. Following the completion of dosing, segments of skin from the site of infection were excised and cultured. The concentration of ME1111 in the back skin of guinea pigs increased with formulation concentration and correlated with mycological efficacy. We revealed the concentration required for ME1111 to be effective at the site of infection. Further analysis is needed to predict the efficacy of topical agents for onychomycosis by analyzing the relationship between PK/PD around the nail bed and factors such as subungual penetration and permeability.

Development of microemulgel formulations with varied permeation enhancers for transungual delivery of luliconazole in onychomycosis management

Luliconazole-loaded microemulgels containing different permeation enhancers were formulated for transungual drug delivery for the management of onychomycosis, onychomycosis, which affects nails. The physicochemical properties like droplet size, zeta potential, pH, viscosity, spreadability, extrudability, oil binding capacity, drug content, and microscopic study were evaluated. The Pseudo-ternary phase diagram was constructed for the formulation of microemulsions (MEs) by keeping the Km ratio constant at 3:1 and characterized for clarity, mean droplet size, zeta potential, viscosity, pH, transmittance, refractive index, and stability. The ME mean droplet size and zeta potential were found in the range of 38.78 to 171.4 nm, and 0.00 to - 6.6 mV, respectively. Prepared MEs were converted into microemulgel by adding a 2.5% gelling agent (Carbapol 934) in the external phase, and a drug release study was conducted. Formulation E3 showed better drug release and was chosen as the control. Four different penetration enhancers were added separately within E3 and further evaluated for pH, viscosity, spreadability, extrudability, oil binding capacity, drug content, microscopic study, Compatibility study, XRD, and DSC. A favorable docking score was observed between luliconazole and Lanosterol 14-alpha-demethylase. In-vitro cumulative drug release at the end of 24 h from E3-SS, containing sodium sulfide as a penetration enhancer, was found to be 94.70% and was 2 times more than the control formulation. Ex-vivo transungual permeation studies through cutting nail clippings were found to be in the range of 28.18 - 36.52 µg/mm2. The microemulgels tagged as E3, E3-SS, and E3-SL showed a significant zone of inhibition against Candida albicans and Aspergillus fumigatus as compared to the marketed formulation.

DNA-Chip-basierte Diagnose der Onychomykose und Tinea pedis

HINTERGRUND UND ZIELE

Onychomykose (OM) und Tinea pedis (TP) sind häufige Pilzinfektionen der Haut. Aktuell basiert die Diagnose vornehmlich auf mikroskopischem Direktnachweis und/oder Kultur. Beide Methoden haben jedoch eine geringe bis mäßige Sensitivität und benötigen teilweise mehrere Wochen, bis endgültige Laborergebnisse vorliegen. Um die Diagnose kutaner Pilzinfektionen zu verbessern, wurden PCR-basierte Methoden entwickelt. Hier haben wir hier die Sensitivität und Spezifität einer Chip-basierten Multiplex-PCR mit mikroskopischen Direktnachweis und verglichen.

PATIENTEN UND METHODIK

In einer monozentrischen, prospektiven Studie wurden bei Patienten mit Verdacht auf OM (n  =  67) oder TP (n  =  73) Schuppenpräparate entnommen und mittels mikroskopischem Direktnachweis, Kultur und DNA-Chip-Technologie der Erregernachweis durchgeführt. In einem weiteren Ansatz wurde überprüft, ob Abstriche als Alternative zur Entnahme eines Schuppenpräparates verwendet werden können. Hierfür wurden 24 weitere OM/TP-Patienten rekrutiert und die Ergebnisse der DNA-Chip-Technologie aus Abstrichen mit denen aus den Schuppenpräparaten verglichen.

ERGEBNISSE

Im Vergleich aller Methoden hatte die DNA-Chip-Technologie die höchste Sensitivität, eine Kombination von DNA-Chip-Technologie mit mikroskopischem Direktnachweis erhöhte dies weiter. Ergebnisse dieser kombinierten Labordiagnostik sind innerhalb von 24 Stunden verfügbar. Der Vergleich der Probenentnahmetechniken (Abstrich beziehungsweise Schuppenpräparat) zeigte vergleichbare Ergebnisse.

SCHLUSSFOLGERUNGEN

Die molekulare Diagnostik (mittels DNA-Chip-Technologie) hat eine hohe Sensitivität für die OM- und TP-Diagnostik, insbesondere in Kombination mit dem mikroskopischen Direktnachweis.

Biodiversity of mycobial communities in health and onychomycosis

Onychomycosis (OM) is a common fungal nail infection. Based on the rich mycobial diversity in healthy toenails, we speculated that this is lost in OM due to the predominance of a single pathogen. We used next generation sequencing to obtain insights into the biodiversity of fungal communities in both healthy individuals and OM patients. By sequencing, a total of 338 operational-taxonomic units were found in OM patients and healthy controls. Interestingly, a classifier distinguished three distinct subsets: healthy controls and two groups within OM patients with either a low or high abundance of Trichophyton. Diversity per sample was decreased in controls compared to cases with low Trichophyton abundance (LTA), while cases with a high Trichophyton abundance (HTA) showed a lower diversity. Variation of mycobial communities between the samples showed shifts in the community structure between cases and controls—mainly driven by HTA cases. Indeed, LTA cases had a fungal β-diversity undistinguishable from that of healthy controls. Collectively, our data provides an in-depth characterization of fungal diversity in health and OM. Our findings also suggest that onychomycosis develops either through pathogen-driven mechanisms, i.e., in HTA cases, or through host and/or environmental factors, i.e., in cases with a low Trichophyton abundance.

What can GP data tell us about the treatment of onychomycosis in the UK?

Background

Treatment of onychomycosis is challenging, and there is much literature on optimal treatment strategies. In contrast, information on how onychomycosis is actually treated in primary care is scarce. Information on practice is important as it can reveal much, such as, to what extent national guidelines are followed and which population groups seek/receive treatment or do not do so.

Objectives

To describe the pattern of onychomycosis treatment in primary care in the UK, by patient's gender and age.

Methods

A population‐based retrospective cross‐sectional study was conducted. The Health Improvement Network (THIN) database was used to calculate incidence rates of onychomycosis in the years 2001–2017. The prescription of oral and topical anti‐fungal drugs to patients with onychomycosis was reviewed.

Results

THIN data showed an onychomycosis incidence rate of about 50 per 100,000. More males than females (52% vs. 48%), and more people aged 50–59 years had received treatment for onychomycosis. Oral terbinafine was the most commonly prescribed drug, followed by topical amorolfine, although terbinafine was used more commonly by men and amorolfine by women. Patients with onychomycosis were also prescribed other antifungals, including itraconazole, griseofulvin, tioconazole, ketoconazole shampoo, fluconazole and clotrimazole. A greater proportion of women, compared to men, were prescribed fluconazole.

Conclusions

Onychomycosis treatment in primary care in the UK is broadly in concordance with national guidelines.

Treatment and management strategies of onychomycosis

Onychomycosis is one of the most prevalent and severe nail fungal infections, which is affecting a wide population across the globe. It leads to variations like nail thickening, disintegration and hardening. Oral and topical drug delivery systems are the most desirable in treating onychomycosis, but the efficacy of the results is low, resulting in a relapse rate of 25-30%. Due to systemic toxicity and various other disadvantages associated with oral therapy like gastrointestinal, hepatotoxicity, topical therapy is commonly used. Topical therapy improves patient compliance and reduces the cost of treatment. However, due to poor penetration of topical therapy across the nail plate, research is focused on different chemical, mechanical and physical methods to improve drug delivery. Penetration enhancers like Thioglycolic acid, Hydroxypropyl-β-cyclodextrin (HP-β-CD), Sodium lauryl sulfate (SLS), carbocysteine, N-acetylcysteine etc. have shown results enhancing the drug penetration across the nail plate. Results with physical techniques such as iontophoresis, laser and Photodynamic therapy are quite promising, but the long-term suitability of these devices is in need to be determined. In this article, a brief analysis of the treatment procedures, factors affecting drug permeation across nail plate, chemical, mechanical and physical devices used to increase the drug delivery through nails for the onychomycosis management has been achieved.

The first case of fingernail onychomycosis due to Neoscytalidium novaehollandiae, molecular identification and antifungal susceptibility

Onychomycosis is considered a fungal nail infection caused mainly by dermatophytes, yeasts and non-dermatophyte molds including dematiaceous fungi. Onychomycosis caused by non-dermatophyte molds is a health problem in the medical environment as the patients frequently return to outpatient clinics seeking new therapeutic modalities. Here, we report the first case of onychomycosis caused by a black fungus, Neoscytalidium novaehollandiae, in the right hand finger nail of a 52-year-old Iranian female with no history of immunodeficiency and underlying disease. The pattern of nail involvement was recognized as total dystrophic onychomycosis. Examination of nail scrapings with potassium hydroxide revealed brown, septate and branching sub-hyaline to dark-colored hyphae. The black fungus isolated in culture was identified as Neoscytalidium novaehollandiae by molecular analysis. The patient received oral terbinafine plus ciclopirox nail lacquer twice a week and began responding to the treatment three months after initial antifungal therapy. Additional four weeks' use of terbinafine plus ciclopirox nail lacquer completely resolved the clinical manifestations of onychomycosis. After four months, both microscopy and culture were negative.

A systematic review and meta-analysis on the epidemiology, casual agents and demographic characteristics of onychomycosis in Iran

Onychomycosis or fungal nail infection is one of the most common fungal infections. Nearly 50% of all nail disorders are caused by fungi. This systematic review and meta-analysis was conducted to determine the prevalence of onychomycosis across Iran. We searched English and Persian databases for studies reporting the epidemiologic features of onychomycosis in Iranian people from January 2000 to December 2018. Literature search revealed 307 studies, of which 24 studies met the eligibility criteria. In order to identifying the existence of publication bias among studies, funnel plots were used. The results of the meta-analysis were visualized as a forest plot representing the prevalence estimates of each study. Heterogeneity was also analyzed using the I², Chi², and Tau² statistics. A high level of I² and Chi² was obtained among studies, which provides evidence of notable heterogeneity between studies. The results of current study revealed that the highest prevalence of onychomycosis was related to Mazandaran and Tehran provinces, respectively. As in the literature hypothesized shift in etiologic agents from yeasts to dermatophytes or molds could not be confirmed. Females were affected more frequently than males and in both sexes the highest incidence of infection occurrence was at the ages of >50 years. It seems the highest prevalence of onychomycosis in Mazandaran and Tehran provinces is due to the concentration of specialist doctors and research centers in these two provinces compared with others which leads to more detection and more care of the disease. Therefore, further educational strategies in order to accurate diagnosis in other provinces is necessary to reduce the risk of onychomycosis in Iran.

Epidemiological and Mycological Aspects of Onychomycosis in Dakar (Senegal)

Onychomycosis is a fungal nails infection often caused by yeasts, dermatophytes and molds. It is an important public health concern due to its high prevalence, the problem of diagnostics, and the poor response to treatments. The objective of this study was to evaluate the epidemiological and microbiological profile of onychomycosis diagnosed at the Laboratory of Parasitology-Mycology of the National University Hospital of Fann in Dakar, Senegal, from 2012 to 2016. A retrospective and descriptive study was performed from January 2012 to December 2016 in a patient attending the laboratory of Parasitology-Mycology at the Fann teaching hospital. Socio-demographic, clinical and biological data were collected from the bench registers. Samples from the lesions were tested using direct microscopy and cultured on a Sabouraud-Chloramphenicol and Sabouraud-Chloramphenicol-Actidione medium. A descriptive analysis was done using Stata IC 12 software. The significance level of different tests was set at 5% two-side. A total of 469 patients were included in this study. The mean age of the study population was 33.2 ± 15.2 years, and the sex ratio was 0.52. The prevalence of onychomycosis was 48.4% (227/469). The main clinical presentations were disto-lateral subungual onychomycosis (37.9%) and onyxis (46.5%). Identified fungal species were Candida albicans (42.7%), Candida spp (39.5%), Trichophyton soudanense (10.1%), Fusarium spp (5.3%), and Candida tropicalis (2.6%). Candida albicans was more frequent in subjects over 15 years of age (43.6%) and women (45%). However, Trichophyton soudanense was higher in patients under 15 years old (17.4%) as well as in male subjects (18.8%). In conclusion, onychomycosis is a common cause of consultation in health facilities. Candida albicans and Trichophyton Soudanense are the main fungal species causing onychomycosis. A better understanding of the epidemiology of onychomycosis as well as the spectrum of the pathogen could contribute to improve the management of the infection.

Toenail alterations in chronic venous disease patients are not always of mycotic origin

Objective

The prevalence of toenail alterations in chronic venous disease has only rarely been studied. We aimed to establish the frequency and clinical characteristics of toenail onychomycosis in chronic venous disease.

Methods

We included 80 adult patients, in all stages of chronic venous disease. Onychomycosis was confirmed by mycological examination. The clinical type of onychomycosis and the onychomycosis severity index were determined. Clinical characteristics of non-fungal nail changes were also analyzed.

Results

We included 58 women and 22 men, with a mean age of 67.0 years. Pathological toenail changes were observed in 83.8% of patients. Onychomycosis was confirmed in 33.8% of all patients and was more frequent in higher clinical stages of chronic venous disease (p = 0.009). Trichophyton rubrum was the leading causative pathogen. Disto-lateral onychomycosis was most commonly present. Average onychomycosis severity index was 23.1.

Conclusion

Onychomycosis accounted for 40% of all toenail alterations. Patients with chronic venous disease often have severe and difficult to treat toenail onychomycosis.

The prevalence and etiological factors of onychomycosis in psoriatic patients

Introduction

The role of a number of inherited, acquired and environmental factors has been identified to increase the risk of onychomycosis. The literature data on psoriasis as a risk factor are contradictory. The potential relationship between these pathologies is very important as it influences the patient management.

Aim

To evaluate the frequency of onychomycosis and etiological factors in patients with psoriasis compared to controls.

Material and methods

The studied group (n = 2427) included 2325 patients with nail abnormalities raising a clinical suspicion of nail onychomycosis (with no history of psoriasis) and 102 psoriatic inpatients. The control group included 100 patients with clinically normal nails. The assessment of psoriasis severity using Nail Psoriasis Severity Index (NAPSI) and Psoriasis Area and Severity Index (PASI) was performed in all psoriatic patients. The presence of fungi was confirmed in direct microscopy and culture.

Results

A significantly higher incidence of onychomycosis was observed in psoriatic patients as well as in non-psoriatic patients with clinically abnormal nails compared to controls. The prevalence of onychomycosis did not differ significantly between psoriatic patients and non-psoriatic patients with nail alterations. The characteristics of isolated fungi differed significantly between psoriatic and non-psoriatic patients. NAPSI ≥ 40 and receiving systemic treatment increased the risk of onychomycosis in psoriatic patients.

Conclusions

The presented study showed a relatively high prevalence of onychomycosis in patients with psoriasis, what confirms the accuracy of performing screening mycological examination in this group. Further studies are warranted to evaluate the role of specific risk factors, explain the differences observed in previous studies and to determine optimal patient management.

In Vitro Human Onychopharmacokinetic and Pharmacodynamic Analyses of ME1111, a New Topical Agent for Onychomycosis

ME1111 is a novel antifungal agent currently under clinical development as a topical onychomycosis treatment. A major challenge in the application of topical onychomycotics is penetration and dissemination of antifungal agent into the infected nail plate and bed. In this study, pharmacokinetic/pharmacodynamic parameters of ME1111 that potentially correlate with clinical efficacy were compared with those of marketed topical onychomycosis antifungal agents: efinaconazole, tavaborole, ciclopirox, and amorolfine. An ME1111 solution and other launched topical formulations were applied to an in vitro dose model for 14 days based on their clinical dose and administration. Drug concentrations in the deep layer of the nail and within the cotton pads beneath the nails were measured using liquid chromatography-tandem mass spectrometry. Concentrations of ME1111 in the nail and cotton pads were much higher than those of efinaconazole, ciclopirox, and amorolfine. Free drug concentrations of ME1111 in deep nail layers and cotton pads were orders of magnitude higher than the MIC₉₀ value against Trichophyton rubrum (n = 30). Unlike other drugs, the in vitro antifungal activity of ME1111 was not affected by 5% human keratin and under a mild acidic condition (pH 5.0). The in vitro antidermatophytic efficacy coefficients (ratio of free drug concentration to MIC₉₀s against T. rubrum) of ME1111, as measured in deep nail layers, were significantly higher than those of efinaconazole, tavaborole, ciclopirox, and amorolfine (P < 0.05). This suggests that ME1111 has excellent permeation of human nails and, consequently, the potential to be an effective topical onychomycosis treatment.

Häufigkeit und Einteilung kutaner Manifestationen bei rheumatoider Arthritis

HINTERGRUND UND FRAGESTELLUNG

Hautveränderungen bei rheumatoider Arthritis (RA) sind nur in wenigen Studien an größeren Patientenkollektiven untersucht. Deshalb sollen hier die aktuelle Prävalenz und das Spektrum an Hautveränderungen bei RA unter Berücksichtigung von Krankheitsaktivitäts-Scores, Anti-CCP-Antikörpern sowie neueren medikamentösen Therapien erfasst werden.

PATIENTEN UND METHODIK

Zwischen November 2006 und Juli 2007 wurden prospektiv 214 Patienten, die im Funktionsbereich Rheumatologie mit RA behandelt wurden, erfasst.

ERGEBNISSE

Bei 27,5 % der Untersuchten wurden RA-assoziierte Hautveränderungen beobachtet, wobei es sich fast ausschließlich um Rheumaknoten handelte. Signifikant gehäuft traten Rheumaknoten bei längerer Erkrankungsdauer, Nachweis von Rheumafaktoren und Anti-CCP-Antikörpern, aber auch unter Gabe von Leflunomid und TNFα-Blockern auf. Vergleichsweise niedrige Prävalenzen wurden hingegen für die "palisadenförmige neutrophile und granulomatöse Dermatitis" und die "rheumatoide Vaskulitis" ermittelt.

SCHLUSSFOLGERUNGEN

Trotz zunehmend frühzeitiger Therapie der RA und dem Einsatz neuerer Medikamente ist die Prävalenz von Rheumaknoten als wichtigste Manifestation der RA am Hautorgan hoch. Deren verstärkte Ausbildung unter Leflunomid und TNFα-Blockern könnte ein Hinweis dafür sein, dass bei der Entstehung von Rheumaknoten eine pathogenetische Wegstrecke eine Rolle spielt, die von den Therapeutika nur unzureichend beeinflusst wird. Hingegen scheinen die palisadenförmige neutrophile und granulomatöse Dermatitis und die "rheumatoide Vaskulitis" durch neuere Medikamente besser beeinflussbar zu sein.

Incidence and classification of cutaneous manifestations in rheumatoid arthritis

BACKGROUND AND OBJECTIVE

There have only been few studies examining rheumatoid arthritis (RA)-related skin manifestations in larger patient populations. Herein, we present current data on the prevalence and spectrum of cutaneous lesions in RA, addressing disease activity scores, anti-CCP antibodies as well as novel pharmacological approaches.

PATIENTS AND METHODS

Between November 2006 and July 2007, 214 patients with RA treated at the Division of Rheumatology, University Hospital Jena, Germany, were prospectively examined.

RESULTS

27.5 % of patients exhibited RA-related skin manifestations, almost all of which were rheumatoid nodules. These lesions occurred significantly more frequently in patients with longstanding disease, those testing positive for rheumatoid factor and anti-CCP-antibodies, as well as individuals on leflunomide and TNF-alpha antagonists. Comparatively lower prevalence rates were observed for palisading neutrophilic and granulomatous dermatitis and rheumatoid vasculitis.

CONCLUSIONS

Despite increasingly early treatment of RA and use of novel pharmacological agents, there is a high prevalence of rheumatoid nodules, which represent the most common cutaneous manifestation in RA. The higher prevalence of rheumatoid nodules in patients on leflunomide and TNF-alpha antagonists might be an indication that pharmacological treatment has only limited effects on their formation, possibly due to pathogenetic pathways that are only inadequately affected by drug therapies. By contrast, palisading neutrophilic and granulomatous dermatitis and rheumatoid vasculitis appear to respond better to novel pharmacological agents.

New Antifungal Agents and New Formulations Against Dermatophytes

A variety of oral and topical antifungal agents are available for the treatment of superficial fungal infections caused by dermatophytes. This review builds on the antifungal therapy update published in this journal for the first special issue on Dermatophytosis (Gupta and Cooper 2008;166:353-67). Since 2008, there have not been additions to the oral antifungal armamentarium, with terbinafine, itraconazole, and fluconazole still in widespread use, albeit for generally more severe or recalcitrant infections. Griseofulvin is used in the treatment of tinea capitis. Oral ketoconazole has fallen out of favor in many jurisdictions due to risks of hepatotoxicity. Topical antifungals, applied once or twice daily, are the primary treatment for tinea pedis, tinea corporis/tinea cruris, and mild cases of tinea unguium. Newer topical antifungal agents introduced include the azoles, efinaconazole, luliconazole, and sertaconazole, and the oxaborole, tavaborole. Research is focused on developing formulations of existing topical antifungals that utilize novel delivery systems in order to enhance treatment efficacy and compliance.

Prevalence and Epidemiology of Onychomycosis

The prevalence of onychomycosis has been estimated at approximately 6.48% (95% confidence interval 6.09–6.88%) within the Canadian population. Dermatophytes are the most commonly cultured organisms, appearing in approximately 75 to 91% of nails with fungal involvement, with Trichophyton rubrum and Tricophyton mentagrophytes most commonly isolated. However, Candida spp and nondermatophyte molds are also sometimes cultured. The most common presentation is distal and lateral subungual onychomycosis (DLSO), which can involve 75% of patients with pedal onychomycosis. The distribution of DLSO, superficial white onychomycosis, and proximal subungual onychomycosis (PSO) has been reported to be 360:59:1 in patients with mycologic confirmation of onychomycosis; however, some reported that the incidence of PSO is slightly higher in immunocompromised individuals. Age, gender, family history, and the presence of tinea pedis are all elements associated with a nail fungal infection. In addition, many conditions, including diabetes mellitus, immune disorders, and vascular disease, have been associated with the presence of onychomycosis. When choosing the best treatment regimen for individuals with onychomycosis, it is very important to consider all of the factors involved, including the infecting species, the presentation of the disease, the level of disease progression, and its predisposing factors.

The prevalence of unsuspected onychomycosis and its causative organisms in a multicentre Canadian sample of 30 000 patients visiting physicians' offices

BACKGROUND

Onychomycosis is difficult to treat and a concern for many patients. Prevalence estimates of onychomycosis in North American clinic samples have been higher than what has been reported for general populations.

OBJECTIVE

A large, multicentre study was conducted to estimate the prevalence of toenail onychomycosis in the Canadian population.

METHODS

Patients were recruited from the offices of three dermatologists and one family physician in Ontario, Canada. Nail samples for mycological testing were obtained from normal and abnormal-looking nails. This sample of 32 193 patients includes our previous published study of 15 000 patients.

RESULTS

Abnormal nails were observed in 4350 patients. Of these, the prevalence of culture-confirmed toenail onychomycosis was estimated to be 6.7% (95% CI, 6.41-6.96%). Following sex and age adjustments for the general population, the estimated prevalence of toenail onychomycosis in Canada was 6.4% (95% CI, 6.12%-6.65%). The distribution of fungal organisms in culture-confirmed onychomycosis was 71.9% dermatophytes, 20.4% non-dermatophyte moulds and 7.6% yeasts. Toenail onychomycosis was four times more prevalent in those over the age of 60 years than below the age of 60 years.

CONCLUSION

The present data highlights that onychomycosis may be a growing medical concern among ageing patients.

Causative Agents of Onychomycosis: A 7-Year Study

BACKGROUND

Onychomycosis is principally caused by dermatophyte species, but nondermatophyte molds and yeasts have also been involved, causing different clinical manifestations. The aim of this investigation is to determine the clinicomycological and epidemiological profile of the etiologic agents of onychomycosis.

METHODS

The study population included 9,785 suspected cases of onychomycosis referred to the Medical Mycology Reference Laboratory in Isfahan, Iran, during 2007-2014. Nail clipping was collected in sterile Petri dishes for direct microscopic examination and culture. Clinical isolates were identified by using phenotypic tests and molecular techniques.

RESULTS

Of total 9,785 cases with clinical suspicion of onychomycosis comprised in the present study, 1,284 patients (13.1%) were positive by direct microscopy. Age range of patients was between 1 and 82 years. Housewives were the commonest infected population. Candida albicans was the most prevalent species isolated from patients in this study (34.9%) followed by Trichophyton interdigitale (11.7%) and Aspergillus flavus (9.1%).

CONCLUSION

The pattern of causative agents and clinical signs of onychomycosis is altering region to region, so repeated epidemiological surveys of onychomycosis seems to be fundamental. The present study provides novel and appropriate epidemiologic data of onychomycosis for the better prevention and treatment of this fungal infection.

An investigation of how fungal infection influences drug penetration through onychomycosis patient's nail plates

The treatment of onychomycosis remains problematic even though there are several potent antifungal agents available for patient use. The aim of this investigation was to understand whether the structural modifications that arise when a patient’s nail become infected plates influences the permeation of drugs into the nail following topical application. It was hoped that through improving understanding of the nail barrier in the diseased state, the development of more effective topical treatments for onychomycosis could be facilitated. The permeation of three compounds with differing hydrophobicities, caffeine, terbinafine and amorolfine (clog D at pH 7.4 of −0.55, 3.72 and 4.49 respectively), was assessed across both healthy and onychomycosis infected, full thickness, human nail plate sections. Transonychial water loss (TOWL) measurements performed on the healthy and diseased nails supported previous observations that the nail behaves like a porous barrier given the lack of correlation between TOWL values with the thicker, diseased nails. The flux of the more hydrophilic caffeine was twofold greater across diseased in comparison with the healthy nails, whilst the hydrophobic molecules terbinafine and amorolfine showed no statistically significant change in their nail penetration rates. Caffeine flux across the nail was found to correlate with the TOWL measurements, though no correlation existed for the more hydrophobic drugs. These data supported the notion that the nail pores, opened up by the infection, facilitated the passage of hydrophilic molecules, whilst the keratin binding of hydrophobic molecules meant that their transport through the nail plate was unchanged. Therefore, in order to exploit the structural changes induced by nail fungal infection it would be beneficial to develop a small molecular weight, hydrophilic antifungal agent, which exhibits low levels of keratin binding.

Characterization of Antifungal Activity and Nail Penetration of ME1111, a New Antifungal Agent for Topical Treatment of Onychomycosis

Fungal nail infection (onychomycosis) is a prevalent disease in many areas of the world, with a high incidence approaching 23%. Available antifungals to treat the disease suffer from a number of disadvantages, necessitating the discovery of new efficacious and safe antifungals. Here, we evaluate the in vitro antifungal activity and nail penetration ability of ME1111, a novel antifungal agent, along with comparator drugs, including ciclopirox, amorolfine, terbinafine, and itraconazole. ME1111 showed potent antifungal activity against Trichophyton rubrum and Trichophyton mentagrophytes (the major etiologic agents of onychomycosis) strains isolated in Japan and reference fungal strains with an MIC range of 0.12 to 0.5 mg/liter and an MIC50 and MIC90 of 0.5 mg/liter for both. Importantly, none of the tested isolates showed an elevated ME1111 MIC. Moreover, the antifungal activity of ME1111 was minimally affected by 5% wool keratin powder in comparison to the other antifungals tested. The ME1111 solution was able to penetrate human nails and inhibit fungal growth in a dose-dependent manner according to the TurChub assay. In contrast, 8% ciclopirox and 5% amorolfine nail lacquers showed no activity under the same conditions. ME1111 demonstrated approximately 60-fold-greater selectivity in inhibition of Trichophyton spp. than of human cell lines. Our findings demonstrate that ME1111 possesses potent antidermatophyte activity, maintains this activity in the presence of keratin, and possesses excellent human nail permeability. These results suggest that ME1111 is a promising topical medication for the treatment of onychomycosis and therefore warrants further clinical evaluation.

Mechanism of Action of ME1111, a Novel Antifungal Agent for Topical Treatment of Onychomycosis

Despite the existing treatment options for onychomycosis, there remains a strong demand for potent topical medications. ME1111 is a novel antifungal agent that is active against dermatophytes, has an excellent ability to penetrate human nails, and is being developed as a topical agent for onychomycosis. In the present study, we investigated its mechanism of action. Trichophyton mentagrophytes mutants with reduced susceptibility to ME1111 were selected in our laboratory, and genome sequences were determined for 3 resistant mutants. The inhibitory effect on a candidate target was evaluated by a spectrophotometric enzyme assay using mitochondrial fractions. Point mutations were introduced into candidate genes by a reverse genetics approach. Whole-genome analysis of the 3 selected mutants revealed point mutations in the structural regions of genes encoding subunits of succinate dehydrogenase (complex II). All of the laboratory-generated resistant mutants tested harbored a mutation in one of the subunits of succinate dehydrogenase (SdhB, SdhC, or SdhD). Most of the mutants showed cross-resistance to carboxin and boscalid, which are succinate dehydrogenase inhibitors. ME1111 strongly inhibited the succinate-2,6-dichlorophenolindophenol reductase reaction in Trichophyton rubrum and T. mentagrophytes (50% inhibitory concentrations [IC50s] of 0.029 and 0.025 μg/ml, respectively) but demonstrated only moderate inhibition of the same reaction in human cell lines. Furthermore, the target protein of ME1111 was confirmed by the introduction of point mutations causing the amino acid substitutions in SdhB, SdhC, and SdhD found in the laboratory-generated resistant mutants, which resulted in reduced susceptibility to ME1111. Thus, ME1111 is a novel inhibitor of the succinate dehydrogenase of Trichophyton species, and its mechanism of action indicates its selective profile.

The Dermatologist's Approach to Onychomycosis

Onychomycosis is a fungal infection of the toenails or fingernails that can involve any component of the nail unit, including the matrix, bed, and plate. It is a common disorder that may be a reservoir for infection resulting in significant medical problems. Moreover, onychomycosis can have a substantial influence on one's quality of life. An understanding of the disorder and updated management is important for all health care professionals. Aside from reducing quality of life, sequelae of the disease may include pain and disfigurement, possibly leading to more serious physical and occupational limitations. Dermatologists, Podiatrists, and other clinicians who treat onychomycosis are now entering a new era when considering treatment options-topical modalities are proving more effective than those of the past. The once sought after concept of viable, effective, well-tolerated, and still easy-to-use monotherapy alternatives to oral therapy treatments for onychomycosis is now within reach given recent study data. In addition, these therapies may also find a role in combination and maintenance therapy; in order to treat the entire disease the practitioner needs to optimize these topical agents as sustained therapy after initial clearance to reduce recurrence or re-infection given the nature of the disease.

Onychomycosis: A Review

Onychomycosis is the most common nail infective disorder. It is caused mainly by anthropophilic dermatophytes, in particular by Trichophyton rubrum and T. mentagrophytes var. interdigitale. Yeasts, like Candida albicans and C. parapsilosis, and molds, like Aspergillus spp., represent the second cause of onychomycosis. The clinical suspect of onychomycosis should be confirmed my mycology. Onychoscopy is a new method that can help the physician, as in onychomycosis, it shows a typical fringed proximal margin. Treatment is chosen depending on the modality of nail invasion, fungus species and the number of affected nails. Oral treatments are often limited by drug interactions, while topical antifungal lacquers have less efficacy. A combination of both oral and systemic treatment is often the best choice.

Amorolfine vs. ciclopirox - lacquers for the treatment of onychomycosis

Amorolfine 5% and ciclopirox 8% nail lacquers are commonly used in topical treatment of onychomycosis. These formulations may be used alone or in combination with oral antifungal agents. Amorolfine and ciclopirox are valuable therapeutic options, however, their usage in monotherapy should be limited. Proper amorolfine and ciclopirox penetration through the nail plate is provided by transungual drug delivery systems. Although amorolfine and ciclopirox have a different mode of action, they both exhibit a broad antifungal activity. The use of antifungal nail lacquers in combination with oral agents, such as terbinafine and itraconazole, improves efficacy of antifungal therapy.

Topical therapy for toenail onychomycosis: an evidence-based review

BACKGROUND

Managing toenail onychomycosis with topical treatments is challenging. It is difficult for topical medication to penetrate the nail plate, and this is reflected in lower cure rates with topical treatment than with oral treatment. However, oral medications may not be suitable for some patients, because of drug interactions; therefore, topical treatments are critical in managing the disease in certain patient populations.

OBJECTIVE

This paper reviews the quality and content of the scientific literature on topical treatments for toenail onychomycosis.

METHODS

PubMed, Ovid (Medline and Embase), Scopus, Cochrane library, and clinicaltrials.gov databases were searched for original clinical reports of topical monotherapy for microscopy and/or culture-confirmed toenail onychomycosis in adults. Studies were evaluated using an onychomycosis study quality scale, which was based on the CONSORT guidelines.

RESULTS

Twenty-five publications (28 studies) were identified and met the inclusion criteria. Thirteen studies scored high ratings on the quality scale. These were randomized controlled trials or randomized comparative trials. Low-quality studies were nonrandomized, open studies that prevented statistical analysis. Most studies reported clinical and mycological cure. The most variation was observed with reporting outcomes of clinical improvement. Amorolfine, ciclopirox, tavaborole, and efinaconazole produced clinical and mycological cure in patients with mild to moderate toenail onychomycosis (<50-65 % nail involvement), with efinaconazole showing the highest rates. Treatments were generally applied daily for 24-48 weeks, with longer treatment and follow-up showing better outcomes.

CONCLUSION

Topical treatment with amorolfine, ciclopirox, tavaborole, or efinaconazole is appropriate for cases of mild to moderate toenail onychomycosis due to dermatophyte or mixed dermatophyte/Candida infection.

The prevalence of culture-confirmed toenail onychomycosis in at-risk patient populations

Onychomycosis is a fungal infection of the nail and is the most common nail affliction in the general population. Certain patient populations are at greater risk of infection and the prevalence of onychomycosis reported in the literature has yet to be summarized across these at-risk groups. We performed a systematic review of the literature and calculated pooled prevalence estimates of onychomycosis in at-risk patient populations. The prevalence of dermatophyte toenail onychomycosis was as follows: general population 3.22% (3.07, 3.38), children 0.14% (0.11, 0.18), the elderly 10.28% (8.63, 12.18), diabetic patients 8.75% (7.48, 10.21), psoriatic patients 10.22% (8.61, 12.09), HIV positive patients 10.40% (8.02, 13.38), dialysis patients 11.93% (7.11, 19.35) and renal transplant patients 5.17% (1.77, 14.14). Dialysis patients had the highest prevalence of onychomycosis caused by dermatophytes, elderly individuals had the highest prevalence of onychomycosis caused by yeasts (6.07%; 95% CI = 3.58, 10.11) and psoriatic patients had the highest prevalence of onychomycosis caused by non-dermatophyte moulds (2.49%; 95% CI = 1.74, 3.55). An increased prevalence of onychomycosis in certain patient populations may be attributed to impaired immunity, reduced peripheral circulation and alterations to the nail plate which render these patients more susceptible to infection.

Oral therapy for onychomycosis: an evidence-based review

INTRODUCTION

Onychomycosis is a very common fungal infection of the nail apparatus; however, it is very hard to treat, even when the causative agent is identified, and usually requires prolonged systemic antifungal therapy. Until the 1990s, oral treatment options included only griseofulvin and ketoconazole, and the cure rate was very low. New generations of antimycotics, such as fluconazole, itraconazole and terbinafine have improved treatment success.

METHODS

Literature was identified by performing a PubMed Ovid MEDLINE, Ovid EMBASE, EBSCO CINAHL, and Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) search. Prospective and randomized clinical trials were chosen to be included in this review. Forty-six trials were included.

RESULTS

Fluconazole, itraconazole and terbinafine are effective in the treatment of onychomycosis and have a good safety profile. When a dermatophyte is the pathogen, terbinafine produces the best results. For Candida and nondermatophyte infections, the azoles, mainly itraconazole, are the recommended therapy.

CONCLUSION

In the majority of the studies, terbinafine treatment showed a higher cure ratio than the other drugs for dermatophyte onychomycosis.

The prevalence of onychomycosis in the global population: a literature study

BACKGROUND

Onychomycosis is a common disorder, and high prevalence figures are commonly cited in the literature.

OBJECTIVES

Evaluate the prevalence of onychomycosis based on published studies.

METHODS

Relevant studies were identified in Medline by using specific search criteria.

RESULTS

Eleven population-based and 21 hospital-based studies were identified. The mean prevalence in Europe and North America was 4.3% [95% Confidence Interval (CI): 1.9-6.8] in the population-based studies, but it was 8.9% (95% CI: 4.3-13.6) for the hospital-based studies. Both population-based and hospital-based studies showed that onychomycosis is more common in toenails and is seen more frequently in males. The main causative agent was a dermatophyte in 65.0% (95% CI: 51.9-78.1) of the cases. Trichophyton rubrum was the single most common fungus and was cultured on average in 44.9% of the cases (95% CI: 33.8-56.0). Moulds were found on average in 13.3% (95% CI: 4.6-22.1) and yeasts in 21.1% (95% CI: 11.0-31.3).

LIMITATIONS

We may not have been able to locate all studies.

CONCLUSIONS

Onychomycosis is a common disorder, but it may not be as common as cited in the literature, because hospital-based studies might overestimate the prevalence of onychomycosis. It is more frequent in males, and toenails are more commonly affected. Dermatophytes, particularly T. rubrum, are the main causative agents.

The prevalence of onychomycosis in psoriatic patients: a systematic review

We systematically reviewed all available literature concerning the prevalence of onychomycosis in patients with nail psoriasis and the distribution of pathogens causing onychomycosis in this specific group of patients. Databases searched were Pubmed, EMBASE and the Cochrane Controlled Clinical Trial Register. All studies reporting on the prevalence of onychomycosis in nail psoriasis were obtained, and quality assessment was determined by the STrengthening the Reporting of OBservational studies in Epidemiology checklist. Literature search revealed 720 studies, of which 10 studies met the inclusion criteria. The major limitation of the review was the heterogeneity of the included studies, which prevented the possibility to conduct a meta analysis. However, the average prevalence of 18.0% of onychomycosis in psoriatic patients seems to be increased when compared with control groups and literature on healthy population, even though the ultimate evidence remains lacking. As in the literature hypothesized shift in causative agents from dermatophytes to yeasts and/or moulds could not be confirmed. The clinical consequence of the relatively high prevalence of onychomycosis in psoriasis may be a general advice to rule out onychomycosis or concomitant onychomycosis in these patients with (suspected) nail psoriasis. This advice is stressed by the relative simplicity of treating the contribution of onychomycosis in the nail dystrophy but also the fact that nail psoriasis mostly is treated by immunosuppressive drugs, like steroids, methotrexate or biologics which may aggravate mycotic nail infections.

[Onychomycosis in Casablanca (Morocco)]

Onychomycosis is the most common nail disease and its prevalence in the literature is estimated between 18 and 50%. The main objective of this study is to describe the epidemiology of onychomycosis and specify the most frequently fungal agents isolated at the University Hospital of Casablanca.

MATERIAL AND METHODS

[corrected] In a retrospective study, performed at the laboratory of Parasitology and Mycology, University Hospital Center of Casablanca (Morocco), over a period of 5 years (2006-2010), mycological results (microscopic study and culture) of 2070 nail samples made during this period were analysed. All onychomycosis cases included in this study had positive microscopy and culture.

RESULTS

Totally, during this period, mycological aetiology was confirmed in 64.5% of cases. Dermatophytes were isolated in 65% of cases (n = 858), yeasts in 30% (n = 405) and molds from 72 nails. Candida albicans is the predominant yeast species in this study (49%), essentially in the fingernails. Onyxis in toenails is essentially dermatophytic, and Trichophyton rubrum is isolated in 75% of onychomycosis of foot.

CONCLUSION

Onychomycosis is a frequent disease in our context, due to diversified fungal agents: dermatophytis in toenail and Candida at the fingernails.

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.

Health-related quality of life in patients with nail disorders

Fingernails and toenails are important organs of our body, serving as protection for the tips of fingers and toes. Fingernails also enhance fine touching and tactile sensitivity, as well as aid in the picking up of small objects. Healthy-looking nails are an important part of an individual's body image, and any nail abnormalities may be considered by patients as a significant cosmetic problem, markedly influencing their self-esteem. However, recent data have indicated that nail lesions are not only important because of cosmetic disfigurement, but may be a symptom of significant morbidity. Severe nail involvement was also shown to negatively impair social functioning and to interfere with work ability, thus markedly influencing a patient's well-being. Based on literature data and our own experience we conclude that nail diseases cause a marked decrease in health-related quality of life in a substantial percentage of patients. Nail changes are an important medical concern for patients and, therefore, nail diseases should raise attention and receive proper care from both physicians and other healthcare providers.