Epidemiology of onychomycosis in Crete, Greece: a 12-year study

Global prevalence of onychomycosis in general and special populations: An updated perspective

BACKGROUND

Onychomycosis is a chronic nail disorder commonly seen by healthcare providers; toenail involvement in particular presents a treatment challenge.

OBJECTIVE

To provide an updated estimate on the prevalence of toenail onychomycosis.

METHODS

We conducted a literature search using PubMed, Embase and Web of Science. Studies reporting mycology-confirmed diagnoses were included and stratified into (a) populations-based studies, and studies that included (b) clinically un-suspected and (c) clinically suspected patients.

RESULTS

A total of 108 studies were included. Based on studies that examined clinically un-suspected patients (i.e., with or without clinical features suggestive of onychomycosis), the pooled prevalence rate of toenail onychomycosis caused by dermatophytes was 4% (95% CI: 3-5) among the general population; special populations with a heightened risk include knee osteoarthritis patients (RR: 14.6 [95% CI: 13.0-16.5]), chronic venous disease patients (RR: 5.6 [95% CI: 3.7-8.1]), renal transplant patients (RR: 4.7 [95% CI: 3.3-6.5]), geriatric patients (RR: 4.7 [95% CI: 4.4-4.9]), HIV-positive patients (RR: 3.7 [95% CI: 2.9-4.7]), lupus erythematosus patients (RR: 3.1 [95% CI: 1.2-6.3]), diabetic patients (RR: 2.8 [95% CI: 2.4-3.3]) and hemodialysis patients (RR: 2.8 [95% CI: 1.9-4.0]). The prevalence of onychomycosis in clinically suspected patients was significantly higher likely due to sampling bias. A high degree of variability was found in a limited number of population-based studies indicating that certain pockets of the population may be more predisposed to onychomycosis. The diagnosis of non-dermatophyte mould onychomycosis requires repeat sampling to rule out contaminants or commensal organisms; a significant difference was found between studies that performed single sampling versus repeat sampling. The advent of PCR diagnosis results in improved detection rates for dermatophytes compared to culture.

CONCLUSION

Onychomycosis is an underrecognized healthcare burden. Further population-based studies using standardized PCR methods are warranted.

A comprehensive review of nondermatophyte mould onychomycosis: Epidemiology, diagnosis and management

Nondermatophyte moulds (NDMs) are widely distributed and can be detected in association with mycotic nails; however, sometimes it can be challenging to establish the role of NDMs in the pathogenesis of onychomycosis (i.e. causative vs. contaminant). In studies where the ongoing invasive presence of NDMs is confirmed through repeat cultures, the global prevalence of NDMs in onychomycosis patients is estimated at 6.9% with the 3 most common genus being: Aspergillus, Scopulariopsis and Fusarium. NDM onychomycosis can, in many cases, appear clinically indistinguishable from dermatophyte onychomycosis. Clinical features suggestive of NDMs include proximal subungual onychomycosis with paronychia associated with Aspergillus spp., Fusarium spp. and Scopulariopsis brevicaulis, as well as superficial white onychomycosis in a deep and diffused pattern associated with Aspergillus and Fusarium. Longitudinal streaks seen in patients with distal and lateral onychomycosis may serve as an additional indicator. For diagnosis, light microscopic examination should demonstrate fungal filaments consistent with an NDM with at least two independent isolations in the absence of a dermatophyte; the advent of molecular testing combined with histological assessment may serve as an alternative with improved sensitivity and turnover time. In most instances, antifungal susceptibility testing has limited value. Information on effective treatments for NDM onychomycosis is relatively scarce, unlike the situation in the study of dermatophyte onychomycosis. Terbinafine and itraconazole therapy (continuous and pulsed) appear effective to varying extents for treating onychomycosis caused by Aspergillus, Fusarium or Scopulariopsis. There is scant literature on oral treatments for Neoscytalidium.

A 5-year single-center study about onychomycosis with a focus on Aspergillus spp. in Albania

BACKGROUND

Onychomycosis is a common nail infection caused by dermatophytes, nondermatophytes molds (NDM), and yeasts. The prevalence of Aspergillus spp. is increasing worldwide. This study aims to describe the epidemiological and microbiological features of onychomycosis, especially for Aspergillus spp.

METHODS

This is a 5-year retrospective study of clinically suspected onychomycosis in one microbiological clinic in Albania. The mycological examination, which included direct microscopic examination of nail scrapings with 20% KOH and culture, was performed on 411 patients. After incubation, we studied the macroscopic characteristics of the colonies, size, shape, and color, and their microscopic examination. We evaluated positive cases for Aspergillus, all cases where Aspergillus was grown in the culture, the microscopy was positive, and the culture was negative for dermatophyte.

RESULTS

Onychomycosis resulted positive in 267 patients (52.9% females vs. 47.1% males). A total of 62.2% resulted infected by dermatophytes, 29.6% by yeasts, and 8.2% by NDM. Onychomycosis resulted more frequent in the age group 15-64 years old (63%). Aspergillus spp. were found in 19 patients from 22 patients with NDM onychomycosis. Males (11 patients) and the age group 15-64 years old (14 patients) were more vulnerable to Aspergillus spp. A. niger, A. flavus, and A. terreus isolated from the nail cultures in our study. The culture resulted more superior to KOH examinations.

CONCLUSIONS

Our study indicates that NDM, including Aspergillus spp., are still rare findings from fungal examinations. However, dermatologist's clinical suspicion and microbiologist's skills are mandatory in diagnosing and properly managing patients with Aspergillus spp.

Cutaneous Fungal Infections Caused by Dermatophytes and Non-Dermatophytes: An Updated Comprehensive Review of Epidemiology, Clinical Presentations, and Diagnostic Testing

Cutaneous fungal infection of the skin and nails poses a significant global public health challenge. Dermatophyte infection, mainly caused by Trichophyton spp., is the primary pathogenic agent responsible for skin, hair, and nail infections worldwide. The epidemiology of these infections varies depending on the geographic location and specific population. However, epidemiological pattern changes have occurred over the past decade. The widespread availability of antimicrobials has led to an increased risk of promoting resistant strains through inappropriate treatment. The escalating prevalence of resistant Trichophyton spp. infections in the past decade has raised serious healthcare concerns on a global scale. Non-dermatophyte infections, on the other hand, present even greater challenges in terms of treatment due to the high failure rate of antifungal therapy. These organisms primarily target the nails, feet, and hands. The diagnosis of cutaneous fungal infections relies on clinical presentation, laboratory investigations, and other ancillary tools available in an outpatient care setting. This review aims to present an updated and comprehensive analysis of the epidemiology, clinical manifestations, and diagnostic testing methods for cutaneous fungal infections caused by dermatophytes and non-dermatophytes. An accurate diagnosis is crucial for effective management and minimizing the risk of antifungal resistance.

Comparison of diagnostic methods in onychomycosis

Aim: Onychomycosis is a chronic fungal infection of the nail bed, plate, or matrix. This study aimed to compare the sensitivity of three diagnostic methods in the diagnosis of onychomycosis. Material and Method: This study included 39 patients with a clinical diagnosis of onychomycosis of the toenails, who presented to Medipol Mega University Hospital between May 2019 and August 2022. Using the nail samples taken from the patients, the results of the direct microscopic examination with standard potassium hydroxide (KOH), histopathological examination performed with periodic acid-Schiff (PAS) staining, and fungal agents that grew in fungal culture were noted. Results: Eleven (28.2%) patients were female, and 28 (71.8%) were male, with the mean age being 43.1±13.9 years. Of the patients, 53.8% had distal subungual onychomycosis and 46.2% had total subungual onychomycosis. The mean disease duration was 38.8±24.5 (12-120) months. Fungal infection was detected on direct microscopic examination with standard KOH in 66.7% of the patients, culture growth in 38.5%, and PAS staining on histopathological examination in 71.8%, and the sensitivities of these methods were determined as 74.3%, 49.2%, and 80%, respectively, with the negative predictive values being 30.8%, 16.7%, and 36.4%, respectively. Conclusion: Among the investigated methods, histopathological examination with PAS staining was found to have the highest sensitivity and negative predictive value in the diagnosis of onychomycosis.

Nonthermal Plasma Effects on Fungi: Applications, Fungal Responses, and Future Perspectives

The kingdom of Fungi is rich in species that live in various environments and exhibit different lifestyles. Many are beneficial and indispensable for the environment and industries, but some can threaten plants, animals, and humans as pathogens. Various strategies have been applied to eliminate fungal pathogens by relying on chemical and nonchemical antifungal agents and tools. Nonthermal plasma (NTP) is a potential tool to inactivate pathogenic and food-contaminating fungi and genetically improve fungal strains used in industry as enzyme and metabolite producers. The NTP mode of action is due to many highly reactive species and their interactions with biological molecules. The interaction of the NTP with living cells is believed to be synergistic yet not well understood. This review aims to summarize the current NTP designs, applications, and challenges that involve fungi, as well as provide brief descriptions of underlying mechanisms employed by fungi in interactions with the NTP components.

Evaluation of different DNA extraction methods based on steel-bullet beating for molecular diagnosis of onychomycosis

BACKGROUND

Considering increased trends toward molecular methods for detection/identification of fungi causing onychomycosis, the aim of this study is comparison three DNA extraction methods based on steel-bullet beating to extract DNA from nail.

METHODS

Ex -vivo onychomycosis model was developed using bovine hoof with Candida albicans and Aspergillus flavus. For two models, total DNA was extracted using the three different methods. In method 1, the extraction and purification were performed by steel-bullet beating and phenol chloroform protocol, respectively. In method 2, a freezing step were applied before beating. The purification step in method 3 was carried out using a commercial kit, although DNA extraction was done similarly to method 1 in that approach. To evaluate the efficacy of each method, the extracted genomic DNA was amplified with Polymerase Chain Reaction (PCR) using Internal Transcribed Spacer (ITS) regions. Moreover, 50 nail samples were evaluated for onychomycosis using direct microscopy examination as well as PCR in order to evaluate the diagnostic efficiency of the optimal DNA extraction method.

RESULTS

Regarding the desirable quality of the extracted DNA, cost effectiveness, and simplicity, method 1 could be used to extract DNA effectively. Additionally, the obtained data showed that PCR had a higher detection rate of fungal agents in the nail samples than direct microscopic examination.

CONCLUSIONS

This study demonstrated that the mechanical disruption of the cell wall by steel-bullet beating is a useful and practical method to improve the quantity and quality of fungal DNA thorough the extraction process.

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

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

Epidemiology of dermatomycoses and onychomycoses in Ireland (2001 to 2020): A single-institution review

Background

Fungal skin infections are recognised as one of the most common health disorders globally, and dermatophyte infections of the skin, hair and nails are the most common fungal infections. Dermatophytes can be classified as anthropophilic, zoophilic or geophilic species based on their primary habitat association, and this classification makes epidemiological analysis useful for the prevention and control of these infections. The Irish contribution to the epidemiology of these infections has been scant, with just two papers (both reporting paediatric tinea capitis only) published in the last 20 years, and none in the last seven.

Objectives

To perform a comprehensive retrospective epidemiological analysis of all dermatological mycology tests performed in University Hospital Limerick over a 20‐year period.

Methods

All mycology laboratory test results were extracted from the Laboratory Information Management System (LIMS, iLab, DXC Technologies) from 2001 to 2020 inclusive for analysis. Specimen types were categorised according to the site of sampling. The data were analysed using Microsoft Excel.

Results

About 12,951 specimens of skin, hair and nails were studied. Median patient age was 42 years (IQR 26–57) with a slight female preponderance (57.2%). Two thirds of samples (67%, n = 8633) were nail, 32% were skin scrapings (n = 4118) and 200 hair samples (1.5%) were received. Zoophilic dermatophytes were more commonly present in females (38% F, 23% M, proportion of dermatophytes) and in those under 10 years of age or from 45 to 70 years (36% and 34% zoophiles, respectively, proportion of dermatophytes), although anthropophiles predominated every age and gender category. Anthropophiles had their highest prevalence in the 10–20 years age category (80% anthropophiles, proportion of dermatophytes), and yeast infections were more prevalent in older patients (29% of >60 year olds vs. 17% of <60 year olds, proportion of all fungal positives). Trichophyton rubrum was the most prevalent pathogen detected, accounting for 53% of all dermatophytes detected, 61% of those detected from nail samples and 34% from skin and hair samples. Trichophyton tonsurans was the most prevalent dermatophyte in tinea capitis, accounting for 37% of dermatophytes detected. Both of these organisms are anthropophilic, and this group showed consistently increased prevalence in proportion to all fungal isolates. The proportion of this dermatophyte class (anthropophiles) increased among both nail samples and skin/hair samples during the study period, from 55% of samples in the first 5 years of the study (2001–2005) to 88% (proportion of dermatophytes) in the final 5 years. Conversely, yeast detection decreased.

Conclusions

This study provides a detailed overview of the epidemiology of the fungal cultures of skin, nail and hair samples in the Mid‐West of Ireland over a 20‐year period. Monitoring this changing landscape is important in identifying likely sources of infections, to identifying potential outbreaks, and may help guide empiric treatment. To the best of our knowledge, this study provides the first detailed analysis from Ireland of fungal detections from skin, hair and nail samples, and is the first epidemiological fungal report of any kind in over 7 years.

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.

A comparative study between two antifungal agents, Luliconazole and Efinaconazole, of their preventive effects in a Trichophyton-infected guinea pig onychomycosis model

An efficacious period of two topical antifungal drugs was compared in a Trichophyton mentagrophytes-infected onychomycosis model in guinea pigs treated with antifungal drugs prior to infection. Luliconazole 5% (LLCZ) and efinaconazole 10% (EFCZ) test solutions were applied to the animals’ nails once daily for 2 weeks followed by a nontreatment period of 2, 4, and 8 weeks. After each nontreatment period, the nails were artificially infected by the fungus. Drug efficacy was quantitatively evaluated by qPCR and histopathological examination of the nails collected following a 4-week post-infection period. The fungal infection was confirmed in the untreated group. Both LLCZ and EFCZ prevented fungal infection in the treated groups with the nontreatment period of 2 weeks. After the nontreatment period of 4 weeks, no infection was observed in the LLCZ-treated group; however, infection into the nail surface and fungal invasion into the nail bed were observed in the EFCZ-treated group. After the nontreatment period of 8 weeks, fungi were found in the nail surface and nail bed in some nails treated with EFCZ; however, no infection was observed in the nail bed of the LLCZ-treated group. The results suggest that LLCZ possesses longer-lasting antifungal effect in nails of the guinea pigs than EFCZ, and that this animal model could be useful for translational research between preclinical and clinical studies to evaluate the pharmacological efficacy of antifungal drugs to treat onychomycosis. This experimentally shown longer-lasting preventive effects of LLCZ could also decrease the likelihoods of onychomycosis recurrence clinically.

Onychomycosis and Tinea Pedis in the Feet of Patients With Diabetes

This study aimed to determine the prevalence of onychomycosis and interdigital tinea pedis in a cohort of Spanish patients with diabetes in whom onychomycosis was clinically suspected (n = 101). Samples from a first toenail scraping and the fourth toe clefts were subjected to potassium hydroxide direct vision and incubated in Sabouraud and dermatophyte test medium. Fifty-eight samples were also analyzed by a pathologist using periodic acid-Schiff staining and Calcofluor white direct fluorescence microscopy. Onychomycosis was only confirmed in 41 patients (40.6%). The most frequent aetiological agent was Trichophyton rubrum, isolated in 10 patients (36%), followed by Candida parapsilosis in 7 patients (25%). Tests on the fourth toe cleft samples were only positive in 11 patients (10.9%), and in all cases, onychomycosis was also diagnosed. Neuroischemic foot was the only significant variable associated with onychomycosis in the univariate analysis (P < .01). A positive result for mycosis in the fourth toe cleft was found in 11 cases (10.9%) and was associated with a history of myocardial infarction (P< .01; odds ratio [OR]: 84.2, confidence interval [CI]: 6.8-1036.4) and neuroischemic foot (P< .01; OR: 13.7, CI: 12.6-71.6) in the multivariate model. In conclusion, the prevalence of onychomycosis and tinea pedis in patients with diabetes in whom onychomycosis was clinically suspected was 40.6% and 10.9%, respectively. In addition, onychomycosis was not always associated with tinea pedis. These results show that clinical diagnosis has low accuracy in people with diabetes mellitus, and that diagnosis should not be based on clinical toenail characteristics alone.

Nondermatophyte mould onychomycosis

Nondermatophyte moulds (NDMs) onychomycosis is often difficult to diagnose as NDMs have been considered contaminants of nails. There are several diagnostic methods used to identify NDMs, however, repeated laboratory isolation is recommended to validate pathogenicity. With NDM and mixed infection (dermatophytes plus NDM) onychomycosis on the rise, accurate clinical diagnosis along with mycological tests is recommended. Systemic antifungal agents such as itraconazole and terbinafine (e.g. pulse regimen: 1 pulse = every day for one week, followed by no treatment for three weeks) have shown efficacy in treating onychomycosis caused by various NDMs such as Aspergillus spp., Fusarium spp., Scopulariopsis brevicaulis, and Onychocola canadensis. Studies investigating topical therapy and devices for NDM onychomycosis are limited. The emergence of antifungal resistance necessitates the incorporation of antifungal susceptibility testing into diagnosis when possible, for the management of recalcitrant infections. Case studies documented in the literature show newer azoles such as posaconazole and voriconazole as sometimes effective in treating resistant NDM onychomycosis. Treatment with broad-spectrum antifungal agents (e.g. itraconazole and efinaconazole) and other combination therapy (oral + oral and/or oral + topical) may be considerations in the management of NDM onychomycosis.

Onychomycosis in Northwestern Greece Over a 7-Year Period

Onychomycosis is considered as one of the major public health problems with a global distribution associated with geographic, demographic and environmental factors, underlying comorbidities and immunodeficiency disorders. This study was conducted to investigate the etiological agents of onychomycosis, in Northwestern Greece during a 7-year period. The study population included 1095 outpatients with clinically suspected onychomycosis that presented to the University Hospital of Ioannina, NW Greece (2011–2017). Samples were examined for causative fungi, and mycological identification was established using standard mycological methods. Demographic data of each patient, comorbidities, localization of infection and history of previous fungal infection were collected. Onychomycosis was diagnosed in 317 of the 1095 suspected cases (28.9%) and the most frequently isolated pathogens were yeasts (50.8%) followed by dermatophytes (36.9%) and non-dermatophyte molds (NDMs) (12.3%). Dermatophytes were mostly involved in toenail onychomycosis (90.6%) and more commonly affected males than females (57.3% vs. 42.7%), while the predominantly isolated pathogen was Τrichophyton rubrum (74.4%) followed by Τrichophyton interdigitale (21.4%). Candida albicans was the most prevalent isolated yeast (82%), whereas among the cases with onychomycosis due to NDMs, Aspergillus spp. were isolated as the principal species (59%). Continuous monitoring should be performed in order to identify possible trends and shifts in species isolation rates and to evaluate the impact of onychomycosis among the general population and high-risk groups.

In vitro antifungal susceptibility testing of fungi in patients with onychomycosis

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

Comparative Study of Traditional Ablative CO2 Laser-Assisted Topical Antifungal with only Topical Antifungal for Treating Onychomycosis: A Multicenter Study

BACKGROUND

The predominance of onychomycosis has been increasing recently. New medications and treatment modalities are being researched for better saturation of the antifungal agents through the nail plate topically because of the low resilience of some patients for the oral antifungal agents. Treatment of onychomycosis, mainly moderate to severe, can be very challenging, expensive, and time consuming.

OBJECTIVE

The objective of this clinical trial is to compare the efficacy and safety of a manually operated ablative CO₂ laser combined with a topical antifungal agent in patients with onychomycosis.

STUDY DESIGN

We conducted an open-label controlled prospective study of 160 eligible patients randomized into control and treatment groups with a 1:1 allocation in the department of dermatology in five different hospitals in Shanghai. It was a 6-month study where both groups were treated with a topical antifungal agent, with the treatment group also receiving ablation by the traditional CO₂ laser once a month for the first 3 months.

RESULTS

The clinical efficacy and mycological cure rate were significantly higher (p < 0.001) for the treatment group. Three (3.75%) patients from the control group and 18 (25%) patients from the treatment group achieved complete nail clearance along with negative potassium hydroxide and negative culture (primary endpoint) results at 24 weeks. Mycological clearance with at least moderate nail clearance (secondary endpoint) for the treatment group was also significantly higher (p < 0.001) for the laser treatment group. The laser treatment was mildly painful but tolerable by the patients. No drug interactions for both groups were encountered.

CONCLUSIONS

The ablative CO₂ laser is a primitive yet effective modality to be considered for the delivery of topical antifungal agents for the management of mild-to-severe onychomycosis. The laser has good tolerance in patients and is a common equipment found in most dermatology units even those without the latest medical technology.

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.

Relationship between antifungal susceptibility profile and virulence factors in Candida albicans isolated from nail specimens

INTRODUCTION

The aim of this study was to evaluate some virulence factors in Candida albicans isolates from patients with onychomycosis and determine the correlation between these factors and the antifungal resistance profile.

METHODS

Seventy species of C. albicans were confirmed using polymerase chain reaction amplification of the HWP1 gene. According to the Clinical & Laboratory Standards Institute guidelines, the susceptibility profile of four antifungal agents was investigated, and the production of aspartyl protease, phospholipase, haemolysin, and biofilm was determined. The correlation between these profiles was also investigated.

RESULTS

The isolates indicated different levels of resistance and production of virulence factors. Significant correlations were observed between the minimum inhibitory concentration (MIC) of fluconazole/itraconazole and biofilm production, between phospholipase production and fluconazole/itraconazole MIC, and between fluconazole MIC and hemolytic activity in C. albicans isolates. The results also showed significant correlations between phospholipase activity and biofilm production.

CONCLUSIONS

Our findings will contribute to a better understanding of the pathogenesis of C. albicans and characterize the relationship between virulence factors and antifungal resistance, which may suggest new therapeutic strategies considering the possible involvement of the virulence mechanism in the effectiveness of treatment.

Epidemiology of Onychomycosis in an Academic Nail Unit in South Greece during a Three-Year Period

Background

Onychomycosis is the most common disease of the nails.

Objective

This retrospective study aimed at evaluating the epidemiology of onychomycosis in adult patients in South Greece during the 2015-2017 period.

Material and Methods

A total of 3,226 patients with clinical signs of possible onychomycosis were included. Diagnosis was confirmed by microscopy with KOH 20% and by culture in Sabouraud agar with and without actidione.

Results

Diagnosis of onychomycosis was confirmed in 27.99% of the patients. Men were infected more often (40.04%) than women (23.30%). Toenails (68.77%) were infected more than fingernails (31.23%) in both sexes. Onychomycosis in fingernails was more common among women (39.74%) than men (18.51%). Men were more often diagnosed with onychomycosis in toenails (81.49%) than women (60.26%). Dermatophytes were the most frequently isolated fungi (34.11%), followed by Candida(29.79%) and non-dermatophyte molds (NDM) (7.20%). In fingernails, the most frequently isolated fungus was Candida spp. (84.04%), followed by dermatophytes (3.55%) and NDM (0.71%). In toenails, dermatophytes (47.99%) were more commonly identified, followed by NDM (10.14%) and Candida spp. (5.15%).

Conclusion

Onychomycosis in Greece follows a pattern of higher incidence in males, with toenails more frequently infected with T. rubrum and fingernails more frequently infected with C. albicans in the present era.

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.

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.

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.

Propolis Extract for Onychomycosis Topical Treatment: From Bench to Clinic

Onychomycosis is a chronic fungal infection of nails, commonly caused by dermatophyte fungi, primarily species of Trichophyton. Because of the limited drug arsenal available to treat general fungal infections and the frequent failure of onychomycosis treatment, the search for new therapeutic sources is essential, and topical treatment with natural products for onychomycosis has been encouraged. Propolis, an adhesive resinous compound produced by honeybees (Apis mellifera), has shown multiple biological properties including significant antifungal and anti-biofilm activities in vitro. In spite of promising in vitro results, in vivo results have not been reported so far. This study assessed an ethanol propolis extract (PE) as a topical therapeutic option for onychomycosis, including its characterization in vitro and its applicability as a treatment for onychomycosis (from bench to clinic). The in vitro evaluation included analysis of the cytotoxicity and the antifungal activity against the planktonic cells and biofilm formed by Trichophyton spp. We also evaluated the capacity of PE to penetrate human nails. Patients with onychomycosis received topical PE treatments, with a 6-month follow-up period. The results of the in vitro assays showed that PE was non-toxic to the cell lines tested, and efficient against both the planktonic cells and the biofilm formed by Trichophyton spp. The results also showed that PE is able to penetrate the human nail. The results for PE applied topically to treat onychomycosis were promising, with complete mycological and clinical cure of onychomycosis in 56.25% of the patients. PE is an inexpensive commercially available option, easy to obtain and monitor. Our results indicated that PE is a promising natural compound for onychomycosis treatment, due to its ability to penetrate the nail without cytotoxicity, and its good antifungal performance against species such as Trichophyton spp. that are resistant to conventional antifungals, both in vitro and in patients.

Evidence for biofilms in onychomycosis

Onychomycosis is a difficult to treat fungal infection of the nails. The chronic nature of onychomycosis contributes to high recurrence rates and the difficulty in treating both dermatophyte and non-dermatophyte infections. It has been hypothesized that the formation of biofilms, sessile, multicellular communities of fungi surrounded by a protective extracellular matrix, allow for fungi to evade current antifungal therapies and contribute to observed antifungal resistance. This review presents the experimental evidence that has accumulated in recent years implicating biofilms in the pathogenesis of onychomycosis. Dermatophytes, non-dermatophyte molds, and yeasts form biofilms in vitro and a model using ex vivo healthy nail fragments has demonstrated biofilm formation on nails for dermatophyte, Candida, and Fusarium species. Implications for disease management are discussed with further research required to incorporate biofilm formation into future drug/device evaluation and treatment protocols.

The frequency, antifungal susceptibility and enzymatic profiles of Candida species in cases of onychomycosis infection

Although the frequency of candidal onychomycosis is increasing daily, there is little information in literature about the epidemiology, pathogenesis, and antifungal susceptibility of this dermatological disease. This study aimed to provide information about the epidemiology, pathogenesis, and azole susceptibility of Candida species isolated from patients living in a region with continental climate. After identification of the isolated strains using conventional methods, proteinase and phospholipase activities were determined by a plate method and biofilm-forming ability was determined using the microplate method. Susceptibility of the same species to fluconazole (FLU), voriconazole (VRC), miconazole (MNZ), itraconazole (ITZ), and ketoconazole (KTZ) were determined by microdilution method. The 50 Candida isolates included 23 C. parapsilosis (46%), 13 C. albicans (26%), 4 C. guilliermondii(8%), 4 C.tropicalis (8%), 2 C.krusei(2%), 1 C.lusitaniae (2%), 1 C. sake (2%), and 1 C. kefyr (2%) isolates. The geometric mean (GM) of the minimum inhibitory concentration (MIC) for FLU, KTZ, VRC, MNZ, and ITZ was 0.4 μg/mL, 0.08 μg/mL, 0.08 μg/mL, 0.2 μg/mL, and 0.6 μg/mL, respectively. Proteinase, phospholipase, and biofilm-forming ability were detected in 18%(9/50), 20%(10/50), and 6%(3/50) of the Candida isolates, respectively. We found that the most frequently isolated species is C.parapsilosis. On the basis of the GM values, the most effective azoles are ketoconazole and voriconazole. The isolated Candida species exhibited low phospholipase, proteinase, and biofilm formation activities.

[Clinical and mycological characteristics of onychomycosis due to Candida at Institut Pasteur of Côte d'Ivoire]

OBJECTIVE

This study aims to study the clinical and mycological characteristics of onychomycosis due to Candida in mycology unit of Institut Pasteur of Côte d'Ivoire.

PATIENTS AND METHODS

This is a retrospective study which was carried out on patients from 1990 to 2016 for mycological diagnosis of onychomycosis and which socio-demographic characteristics, direct examination and culture results were recorded.

RESULTS

In this study, 1898 patient files were selected. The average age of the patients was 31.69 years (standard deviation=15.11) with a sex ratio of 0.87. The frequency of Candida onychomycosis from patients received was 61.7%. Finger nails (67.7%) were more affected by this condition, followed by those of the toes (25.3%). Ninety cases of double localization of the nails of the hands and toes have been found. Candida albicans was the most frequent species accounting for 79.1% of isolated yeasts. Among the non-albicans, C. parapsilosis and C. tropicalis were isolated at the level of the toenails with frequencies rate of 11.2 and 9.6%.

CONCLUSION

Onychomycosis due to Candida are relatively common in Abidjan and are dominated by C. albicans. The mycological confirmation of the fungal etiology in onychopathy and a good hygiene of the nails will allow a better management.

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.

Onychomycosis in the 21st Century: An Update on Diagnosis, Epidemiology, and Treatment

Onychomycosis accounts for 50% of all nail disease cases and is commonly caused by dermatophytes. Diabetes, human immunodeficiency virus, immunosuppression, obesity, smoking, and advancing age are predisposing factors of this fungal infection. Potassium hydroxide and culture are considered the current standard for diagnosing onychomycosis, revealing both fungal viability and species identification. Other diagnostic tests currently available include periodic acid-Schiff staining, polymerase chain reaction techniques, and fluorescent staining. Across 6 recently published epidemiology studies, the global prevalence of onychomycosis was estimated to be 5.5%, falling within the range of previously reported estimates (2%-8%). Newly approved onychomycosis treatments include efinaconazole, tavaborole, and laser therapy with lasers only approved to temporarily increase the amount of clear nail. Additional onychomycosis treatments being investigated include iontophoresis and photodynamic therapy with small open-label studies reported thus far. Preventative strategies, to help decrease recurrence and reinfection rates, include sanitisation of footwear and prophylactic topical antifungal agents.