Hot Topics in Superficial Fungal Infections

Introduction: It has long been accepted that trauma is one of the most important and frequent predisposing factors for onychomycoses. However, the role of direct trauma in the pathogenesis of fungal nail infections has only recently been elucidated in a series of 32 cases of post-traumatic single-digit onychomycosis. The importance of repeated trauma due to foot and toe abnormalities was rarely investigated. Aimof the study: This is a multicenter single-author observational study over a period of 6 years performed at specialized nail clinics in three countries. All patient photographs taken by the author during this period were screened for toenail alterations, and all toe onychomycosis cases were checked for whether they contained enough information to evaluate potential foot and toe abnormalities. Particular attention was paid to the presence of hallux valgus, hallux valgus interphalangeus, hallux erectus, inward rotation of the big toe, and outward rotation of the little toe, as well as splay foot. Only cases with unequivocal proof of fungal nail infection by either histopathology, mycologic culture, or polymerase chain reaction (PCR) were accepted. Results: Of 1653 cases, 185 were onychomycoses, proven by mycologic culture, PCR, or histopathology. Of these, 179 involved at least one big toenail, and 6 affected one or more lesser toenails. Three patients consulted us for another toenail disease, and onychomycosis was diagnosed as a second disease. Eight patients had a pronounced tinea pedum. Relatively few patients had a normal big toe position (n = 9). Most of the cases had a mild to marked hallux valgus (HV) (105) and a hallux valgus interphalangeus (HVI) (143), while hallux erectus was observed in 43 patients, and the combination of HV and HVI was observed 83 times. Discussion: The very high percentage of foot and toe deformations was surprising. It may be hypothesized that this is not only a pathogenetically important factor but may also play an important role in the localization of the fungal infection, as no marked hallux deviation was noted in onychomycoses that affected the lesser toes only. As the management of onychomycoses is a complex procedure involving the exact diagnosis with a determination of the pathogenic fungus, the nail growth rate, the type of onychomycosis, its duration, and predisposing factors, anomalies of the toe position may be important. Among the most commonly mentioned predisposing factors are peripheral circulatory insufficiency, venous stasis, peripheral neuropathy, immune deficiency, and iatrogenic immunosuppression, whereas foot problems are not given enough attention. Unfortunately, many of these predisposing and aggravating factors are difficult to treat or correct. Generally, when explaining the treatment of onychomycoses to patients, the importance of these orthopedic alterations is not or only insufficiently discussed. In view of the problems encountered with the treatment of toenail mycoses, this attitude should be changed in order to make the patient understand why there is such a low cure rate despite excellent minimal inhibitory drug concentrations in the laboratory. Full article

Introda significant: Onychomycosis is the most common nail disorder seen in clinical practice, and it may have significant impact on patient quality of life. Understanding risk factors for onychomycosis may help to devise screening and treatment guidelines for populations that are more susceptible to this infection. Using a national database, we aimed to explore associations between onychomycosis and age, sex, and underlying medical conditions, as well as to examine current onychomycosis treatment trends. Materials and Methods: We performed a nested, matched, case–control study of patients in the All of Us database aged ≥ 18 years (6 May 2018–1 January 2022). Onychomycosis cases were identified using International Classification of Diseases (ICD) and Systematized Nomenclature of Medicine (SNOMED) diagnostic codes (ICD-9 110.1, ICD-10 B35.1, SNOMED 414941008). Demographic information (i.e., age, sex, and race), treatments, and co-diagnoses for onychomycosis patients and case–controls were recorded. Wald’s test applied to multivariate logistic regression was used to calculate odds ratios and p-values between onychomycosis and co-diagnoses. Additionally, 95% confidence intervals were calculated with a proportion test. Results: We included 15,760 onychomycosis patients and 47,280 matched controls. The mean age of onychomycosis patients was 64.9 years, with 54.2% female, 52.8% Non-Hispanic White, 23.0% Black, 17.8% Hispanic, and 6.3% other, which was similar to controls. Patients with onychomycosis vs. controls were more likely to have a co-diagnosis of obesity (46.4%, OR 2.59 [2.49–2.69]), tinea pedis (21.5%, OR 10.9 [10.1–11.6]), peripheral vascular disease (PVD) (14.4%, OR 3.04 [2.86–3.24]), venous insufficiency (13.4%, OR 3.38 [3.15–3.59]), venous varices (5.6%, OR 2.71 [2.47–2.97]), diabetes mellitus (5.6%, OR 3.28 [2.98–3.61]), and human immunodeficiency virus (HIV) (3.5%, OR 1.8 [1.61–2.00]) (p < 0.05, all). The most frequently prescribed oral and topical medications were terbinafine (20.9%) and ciclopirox (12.4%), respectively. The most common therapeutic procedure performed was debridement (19.3%). Over the study period, ciclopirox prescriptions (Spearman correlation 0.182, p = 0.0361) and fluconazole prescriptions increased (Spearman correlation 0.665, p = 2.44 × 10⁻⁴), and griseofulvin (Spearman correlation −0.557, p = 0.0131) and itraconazole prescriptions decreased (Spearman correlation −0.681, p = 3.32 × 10⁻⁶). Conclusions: Our study demonstrated that age, obesity, tinea pedis, PVD, venous insufficiency, diabetes mellitus, and HIV were significant risk factors for onychomycosis. In addition, the most frequent oral and topical onychomycosis medications prescribed were terbinafine and ciclopirox, likely reflective of efficacy and cost considerations. Identifying and managing these risk factors is essential to preventing onychomycosis’ primary infections and recurrences and improving treatment efficacy. Full article

Mass population movements have altered the epidemiology of tinea capitis (TC) in countries receiving refugees. Periodic monitoring of the local pathogen profiles may serve as a basis for both the selection of appropriate empirical antifungal therapy and the implementation of preventive actions. Therefore, we investigated the impact of an unprecedented immigration wave occurring in Greece since 2015 on the epidemiological trends of TC. All microbiologically confirmed TC cases diagnosed during the period 2012–2019 in a referral academic hospital for dermatological disorders in Athens, Greece, were retrospectively reviewed. A total of 583 patients were recorded, where 348 (60%) were male, 547 (94%) were children and 160 (27%) were immigrants from Balkan, Middle Eastern, Asian as well as African countries. The overall annual incidence of TC was 0.49, with a significant increase over the years (p = 0.007). M. canis was the predominant causative agent (74%), followed by T. violaceum (12%), T. tonsurans (7%) and other rare dermatophyte species (7%). M. canis prevalence decreased from 2014 to 2019 (84% to 67%, p = 0.021) in parallel with a three-fold increase in T. violaceum plus T. tonsurans rates (10% to 32%, p = 0.002). An increasing incidence of TC with a shift towards anthropophilic Trichophyton spp. in Greece could be linked to the immigration flows from different socioeconomic backgrounds. Full article

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. Full article

Otomycosis (OM) is a superficial fungal infection of the external auditory canal (EAC) with a worldwide prevalence ranging from 9% to 30%. Commonly, otomycoses are caused by Aspergillus (A.) niger complex and Candida spp. Other causative agents are yeasts of the genera Cryptococcus spp., Rhodotorula spp., Geotrichum candidum, dermatophytes (Trichophyton mentagrophytes), and non-dermatophytes molds (Fusarium spp., Penicillium spp., Mucorales fungi). The widest range of different species causing OM are found in the territories of Iran, India, China, Egypt, Mexico, and Brazil. Fungal infection of the EAC varies from mild to severe forms. It can be acute, subacute, or chronic, and is often unilateral, while the bilateral form is more common in immunocompromised patients. From an epidemiological point of view, tropical and subtropical climates are the most significant risk factor for the development of otomycosis. Other predisposing conditions include clothing habits, EAC hygiene practices, long-term antibiotic therapy, diabetes, and immunodeficiency. Since it is often difficult to distinguish otomycosis from an infection of a different origin, laboratory-based evidence, including standard procedures (microscopy and cultivation), is essential for diagnosis. For the treatment of this superficial fungal infection, there are no official therapeutic guidelines and protocols. However, many antifungals for local application, such as polyene, imidazoles, and allylamines, can be applied, as well as systemic antimycotics (triazoles) in severe forms of infection. Full article