Prevalence, Risk Factors, and Spectrum of Fungi in Patients with Onychomycosis in Addis Ababa, Ethiopia: A Prospective Study

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.

Therapeutic treatment strategies for the management of onychomycosis: a patent perspective

INTRODUCTION

Onychomycosis, a multifactorial fungal infection of the nails, shows a global prevalence of about 5.5% and is responsible for 50% of all nail infections. To develop effective management strategies, it is necessary to understand the etiology, pathophysiology, and risk factors of onychomycosis. Oral route of drug delivery is one of the routes utilized to deliver anti-fungal agents, but, has its own limitations like longer duration of treatment, increased adverse effects, and potential for drug interaction. The ungual route has received greater attention due to its localized, non- invasive action and improved patient compliance.

AREAS COVERED

This review comprehensively discusses conventional onychomycosis therapies and patented novel drug delivery systems for the management of onychomycosis including chemical permeation enhancers, non-particulate drug delivery systems, penetration enhancing devices etc., Databases such as PubMed, ResearchGate, and Google Patents were searched by using the keywords onychomycosis and trans-ungual drug delivery.

EXPERT OPINION

Enormous research has been conducted and is still ongoing to find the best possible novel drug delivery system for onychomycosis management. Approaches like incorporation of herbal constituents in nano-formulations, inkjet printing, laser devices, iontophoretic techniques, etc. can be employed to make safe and effective drug delivery systems which are regulatory compliant.

Non-Dermatophyte Mold Dominated Onychomycosis in Patients Attending a Rank Higher Specialized Dermatology Clinic in Addis Ababa, Ethiopia

Background

Onychomycosis is a common refractory fungal infection associated with significant morbidity. The objective of this study was to determine the prevalence of onychomycosis, and the diversity and species composition of fungal etiological agents.

Materials and Methods

A clinic-based, prospective, non-randomized cross-sectional study was carried out between October 2018 and June 2019 at Rank Higher Specialized Dermatology Clinic, Addis Ababa, Ethiopia. Nail scrapings were collected aseptically from 200 patients clinically identified with nail disorders of fungal origin by dermatologists. Fungal etiological agents were identified microscopically and by culture method following standard procedures.

Results

Among 200 nail scrapings, 161 (80.5%) samples were found out to be culture positive. Of these, 135 (83.9%) samples yielded single colonies while 26 (16.1%) mixed colonies gave a total of 190 isolates. Among the isolates, 25.8% were dermatophytes while 61.1% were non- dermatophytes molds, and 13.1% were yeasts. Females were more likely to present dystrophic nails than men. Patients in the middle age group were more affected. Trichophyton interdigitale, Aspergillus spp, and Candida albicans were the dominant species.

Conclusion

The prevalence rate of onychomycosis in the present study was high. The isolation rate of non-dermatophyte molds was higher than dermatophytes and yeasts. Trichophyton interdigitale, Aspergillus spp, and Candida albicans were the dominant etiological agents. Females and patients in the middle age group were more affected. An increase in the prevalence of non-dermatophyte molds in nail infections dictates further investigation demonstrating how this group of fungi causes onychomycosis.

The epidemiology and etiology of onychomycosis in 2 laboratory centers affiliated to Tehran university of medical sciences during 2019-2020

Background and Objectives

Onychomycosis is caused by dermatophyte species, non-dermatophyte moulds (NDMs), and accounts for roughly 50% of all nail diseases. As the prevalence of onychomycosis is increasing, new epidemiologic documents may help with treatment and prevention. The present investigation aims to determine the epidemiological profile of onychomycosis in 2 mycology laboratories.

Materials and Methods

A cross-sectional study conducted during eight months (2019-2020) on 169 patients with positive nail mycology tests referred to two mycological laboratory centers affiliated with Tehran University of Medical Science. The nail clippings were examined by direct smear and culture. Also, molecular assays were performed if needed.

Results

10% of nail lesions referred to Razi Hospital (RH), and 30% of nail lesions referred to TUMS mycology laboratory were positive. Middle age (40-60) suffer more from onychomycosis. Aspergillus flavus, Trichophyton mentagrophytes, and Candida albicans were the most common etiologic agents in each of the three main classes of fungi causing onychomycosis. Females were more infected. NDMs were the predominant etiologic agents, and toenails were the most common site of onychomycosis.

Conclusion

The pattern of etiologic agents and clinical signs of onychomycosis differs according to geographical region and age, so repeated epidemiological surveys of onychomycosis seem to be fundamental.

MOLECULAR DETECTION OF THE TWO VIRULENCE GENES HWP1 AND ALS1 IN CANDIDA SPECIES ISOLATED FROM ONYCHOMYCOSIS

OBJECTIVE

The aim: This article was aimed to assess the prevalence of Candida species causing nail infections and to investigate the most important virulence genes that cause adhesion.

PATIENTS AND METHODS

Materials and methods: Samples were collected from General Hospital and the outpatient's clinics in Thi-Qar Province, southern Iraq, during the period from January 2021 to May 2021. Samples were inoculated on Sabouraud Dextrose Agar plates containing 0.5 mg chloramphenicol, then Petri dishes were incubated at 30°C under aerobic conditions and observed for Candida species growth for 24-72 hrs. All isolates were identified by morphologic and chromatic properties on CHROMagar and by Api Candida.

RESULTS

Results: Twenty five isolates were obtained from hundred samples, which belong to five species of the genus Candida, distributed in percentage 9(36%), 4(16%), 4(16%), 4(16%) and 3(12%) of C. glabrata, C. krusei, C. albicans, C. famata and C. tropicalis consecutively and one isolate was not identified. Monoplex PCR technique was used to detect virulence genes (hwp1 and als1) of Candida species. Four Candida albicans isolates (16%) were carried of both hwp1 and als1 genes.

CONCLUSION

Conclusions: The virulence gene (hwp1) can be relied upon in molecular detection as a special diagnostic tool of Candida albicans species except other types causing Candidal onychomycosis.

Molecular characterization and antifungal activity against non-dermatophyte molds causing onychomycosis

Onychomycosis is a fungal disease that caused by different types of fungi. Non-dermatophyte molds are a large saprophytic fungi group that live in nature and could affect traumatic nails. The aim of this study was to identify non-dermatophyte molds causing onychomycosis and evaluation of several antifungal activities against the isolates. The samples consisted of 50 non-dermatophyte molds isolated from patients with onychomycosis confirmed by direct and culture examination fungal. DNA was extracted, amplified, and sequenced. Disk diffusion method was used to evaluate itraconazole, fluconazole, ketoconazole, terbinafine, posaconazole, and econazole activity against the isolates. The species identified as: Aspergillus flavus 22 (44%), A. niger 12 (24%), A. fumigates, 3 (6%), A. sydowii 3 (6%), A. terreus 1 (2%), Penicillium commune 2 (4%), P. glabrum 2 (4%), P. chrysogenum, 1 (2%), Fusarium solani 3 (6%) and F. thapsinum 1 (2%). Most of the samples were sensitive to terbinafine, itraconazole, and econazole and 94% of the isolates were resistant to fluconazole. This study showed that Aspergillus species were the most common cause of non-dermatophyte mold onychomycosis and fluconazole was the most resistant antifungals. Care must be taken to choose the appropriate antifungal drug for a better cure.

Epidemiological Characterization of Dermatomycosis in Ethiopia

Background

Superficial mycosis is common worldwide and their epidemiological characteristics are different in different geographical areas and have shown variations in the last decades. The aim of this study was to analyze and characterize the epidemiology of dermatomycosis and their causative fungi species in Ethiopia between 2015 and 2019.

Methods

A laboratory-based cross-sectional study was conducted using the data of mycological examination and culture findings from all patients who visited the Dermatology Department of Arsho Advanced Medical Laboratory, Addis Ababa, Ethiopia. The direct wet mount microscopy and culture data of the isolates were collected from the database of the dermatology unit from 2015 to 2019 after permission was obtained from the laboratory head. The data were double-entered into Microsoft Excel, exported and analyzed using SPSS version 20.

Results

The total prevalence of fungi causing dermatomycosis was 67.7% (760/1122 cases) using direct wet mount microscopy and from these 489/1122 (43.5%) were culture positive. Dermatomycosis was found to be higher among females 694/1122 (61.9%) than male participants. Age group 25–44 years was the most affected 442/1122 (39.4%) followed by 1–14 years old 291/1122 (25.94%). Tinea unguium (50.8%) is the most common type of dermatomycosis followed by tinea capitis (24.1%) and tinea corporis (13.9%). Trichophyton spp. (32%) was the most highly distributed causative agent, followed by Epidermophyton spp. (20.2%) and Aspergillus fumigatus (8.3%).

Conclusion

The retrospective analysis of epidemiological data collected at Arsho Advanced Medical Laboratory since 2015 showed a gradual increase in the frequency of tinea unguium and tinea pedis. However, during the past years, there was a gradual decline in the frequency of tinea corporis. In parallel with this variable pattern, the rate of isolation of non-dermatophytes especially Aspergillus fumigates and Candida species has shown a gradual increment during the past five years.

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.

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.