Dermatophyte infections in children compared to adults in Germany: a retrospective multicenter study in Germany

Epidemiological overview of mucocutaneous fungal infections in Munich

BACKGROUND AND OBJECTIVES

Knowledge about the current spectrum of dermatomycoses is important for diagnosis and therapy.

PATIENTS AND METHODS

A retrospective, monocentric analysis of mucocutaneous fungal infections diagnosed at a large European academic dermatology department in Munich was conducted; 87,229 samples from 48,916 patients from January 1, 2011, to August 30, 2020, were included.

RESULTS

Fungi were detected in 11,513 samples from 48,916 (23.54%), and 36 different species were identified. Candida (C.) albicans was the most common pathogen (5,055 detections; 43.91% of all positive samples), followed by Trichophyton (T.) rubrum (3,076 detections; 26.72% of all positive samples) and Candida parapsilosis (923 detections; 8.02% of all positive samples). Rare pathogens such as Trichophyton raubitschekii were also detected. Coinfections with multiple species were detected in 44 cases.

CONCLUSIONS

Even though C. albicans, T. rubrum, and C. parapsilosis were confirmed as the most common pathogens, rare pathogens should also be considered in clinical practice. The predominant spectrum of fungi differed from that reported in other countries. Furthermore, a difference in the pathogen spectrum could be observed depending on the age group and body site.

Global Demographic Characteristics and Pathogen Spectrum of Tinea Capitis

Tinea capitis is an important superficial fungal infection with a global distribution. It mainly affects prepubertal children and is more common in males. Anthropophilic and zoophilic dermatophytes are responsible for most infections. The pathogen spectrum of tinea capitis varies across different regions and changes over time, and is influenced by multiple factors, such as economic development, changes in lifestyle, immigration and animal distribution. This review aimed to clarify the demographic and etiological characteristics of tinea capitis worldwide and determine the common trends of causative pathogens. By mainly analyzing the literature published from 2015 to 2022, we found that the incidence and demographic characteristics of tinea capitis remained generally stable. Zoophilic Microsporum canis, anthropophilic Trichophyton violaceum and Trichophyton tonsurans were the predominant pathogens. The pathogen spectra in different countries changed in different directions. In some countries, the main pathogen shifted to an anthropophilic dermatophyte, such as T. tonsurans, Microsporum audouinii or T. violaceum; in contrast, it shifted to a zoophilic agent, such as M. canis, in some other countries. Dermatologists are advised to continue monitoring the pathogen spectrum and implement preventive measures according to the reported changes.

Tinea pedis: an updated review

Background

Tinea pedis is one of the most common superficial fungal infections of the skin, with various clinical manifestations. This review aims to familiarize physicians with the clinical features, diagnosis and management of tinea pedis.

Methods

A search was conducted in April 2023 in PubMed Clinical Queries using the key terms 'tinea pedis' OR 'athlete's foot'. The search strategy included all clinical trials, observational studies and reviews published in English within the past 10 years.

Results

Tinea pedis is most often caused by Trichophyton rubrum and Trichophyton interdigitale. It is estimated that approximately 3% of the world population have tinea pedis. The prevalence is higher in adolescents and adults than in children. The peak age incidence is between 16 and 45 years of age. Tinea pedis is more common amongst males than females. Transmission amongst family members is the most common route, and transmission can also occur through indirect contact with contaminated belongings of the affected patient. Three main clinical forms of tinea pedis are recognized: interdigital, hyperkeratotic (moccasin-type) and vesiculobullous (inflammatory). The accuracy of clinical diagnosis of tinea pedis is low. A KOH wet-mount examination of skin scrapings of the active border of the lesion is recommended as a point-of-care testing. The diagnosis can be confirmed, if necessary, by fungal culture or culture-independent molecular tools of skin scrapings. Superficial or localized tinea pedis usually responds to topical antifungal therapy. Oral antifungal therapy should be reserved for severe disease, failed topical antifungal therapy, concomitant presence of onychomycosis or in immunocompromised patients.

Conclusion

Topical antifungal therapy (once to twice daily for 1-6 weeks) is the mainstay of treatment for superficial or localized tinea pedis. Examples of topical antifungal agents include allylamines (e.g. terbinafine), azoles (e.g. ketoconazole), benzylamine, ciclopirox, tolnaftate and amorolfine. Oral antifungal agents used for the treatment of tinea pedis include terbinafine, itraconazole and fluconazole. Combined therapy with topical and oral antifungals may increase the cure rate. The prognosis is good with appropriate antifungal treatment. Untreated, the lesions may persist and progress.

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.

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.

Tinea capitis bei Kindern – ein buntes Krankheitsbild

Bei der Tinea capitis (TC) handelt es sich um eine Infektion der behaarten Kopfhaut durch Dermatophyten, ganz überwiegend durch anthropophile und zoophile Arten. Hauptsächlich sind Kinder betroffen. Die Inzidenz der TC nimmt in Deutschland aktuell aufgrund verschiedener Ursachen zu, wie z. B. der Migrationsbewegung aus Afrika und Reisen. Auch das Erregerspektrum verändert sich. Da das klinische Bild einer TC sehr unterschiedlich sein kann, sind initiale Fehldiagnosen häufig. Um diagnostische Irrtümer und unwirksame Therapieversuche zu vermeiden, sollten Pädiater:innen mit allen Aspekten der TC vertraut sein. Dazu werden die Klinik sowie die Erreger der TC erläutert; des Weiteren werden die Diagnostik sowie leitliniengerechte Therapie der TC dargestellt. Darüber hinaus werden Maßnahmen zur Verhinderung von Reinfektionen oder Infektionen anderer Kinder erklärt.

Consensus for the Treatment of Tinea Pedis: A Systematic Review of Randomised Controlled Trials

Objective: To systematically review literature enabling the comparison of the efficacy of pharmaceutical treatments for tinea pedis in adults. Design: Systematic review of randomised controlled trials (RCTs) with mycological cure as the primary outcome. Secondary outcomes did include the clinical assessment of resolving infection or symptoms, duration of treatment, adverse events, adherence, and recurrence. Eligibility Criteria: Study participants suffering from only tinea pedis that were treated with a pharmaceutical treatment. The study must have been conducted using an RCT study design and recording age of the participant > 16 years of age. Results: A total of seven studies met the inclusion criteria, involving 1042 participants. The likelihood of resolution in study participants treated with terbinafine was RR 3.9 (95% CI: 2.0−7.8) times those with a placebo. Similarly, the allylamine butenafine was effective by RR 5.3 (95% CI: 1.4−19.6) compared to a placebo. Butenafine was similarly efficacious to terbinafine RR 1.3 (95% CI: 0.4−4.4). Terbinafine was marginally more efficacious than itraconazole, RR 1.3 (95% CI: 1.1−1.5). Summary/Conclusion: Topical terbinafine and butenafine treatments of tinea pedis were more efficacious than placebo. Tableted terbinafine and itraconazole administered orally were efficacious in the drug treatment of tinea pedis fungal infection. We are concerned about how few studies were available that reported the baseline characteristics for each treatment arm and that did not suffer greater than 20% loss to follow-up. We would like to see improved reporting of clinical trials in academic literature. Registration name: Treatment’s for athlete’s foot—systematic review with meta-analysis [CRD42020162078].