Epidemiology, clinical presentation and diagnosis of onychomycosis

Abstract

Onychomycosis is a common nail disease, responsible for up to 50% of diseases of the nail. The distribution of different pathogens is not uniform; it depends on various factors such as climate, geography and migration. However, studies have revealed that two dermatophytes, Trichophyton rubrum and Trichophyton mentagrophytes, account for more than 90% of onychomycoses. Onychomycosis can be divided into four major clinical presentations: distal subungal (the most common form of the disease), proximal subungal (the most common form found in patients with human immunodeficiency virus infection), and superficial and total dystrophic onychomycosis. Onychomycosis is a multifactorial disease. Age has a very important effect on the occurrence of onychomycosis, with a correlation between increasing age and infection. Genetics has also been identified as a factor governing the epidemiology of onychomycosis; T. rubrum infection shows a familial pattern of autosomal dominant inheritance. Disease and lifestyle may also play a role in the epidemiology of fungal nail infections. Studies have shown that diabetes, acquired immunodeficiency syndrome and peripheral arterial disease may be independent predictors of onychomycosis. Because of the multifactorial nature of the epidemiology, accurate diagnosis, pertinent treatment and patient education must be paramount when treating the disease.

Prevalence of Candida tropicalis and Candida krusei in onychomycosis in João Pessoa, Paraiba, Brazil from 1999 to 2010

“…Their prevalence is growing, and can be explained by factors such as increased incidence of immunodeficiency, population age, improved medical surveillance, nail care, and genetic susceptibility, along with smoking, environmental (geography, climate), and behavioral factors. For example, the prevalence of onychomycosis in swimmers is at least three times more than for nonswimmers (Faergemann and Baran 2003, Tosti et al 2005, Dahdah and Scher 2006, Zanardi et al 2008. Among the etiologic agents of onychomycosis yeasts, dermatophytes and non-dermatophyte filamentous fungi stand out, with dermatophytes being considered the main causal agents, followed by yeasts (Faergemann and Baran 2003, Ballesté et al 2003, Tosti et al 2005.…”

“…For example, the prevalence of onychomycosis in swimmers is at least three times more than for nonswimmers (Faergemann and Baran 2003, Tosti et al 2005, Dahdah and Scher 2006, Zanardi et al 2008. Among the etiologic agents of onychomycosis yeasts, dermatophytes and non-dermatophyte filamentous fungi stand out, with dermatophytes being considered the main causal agents, followed by yeasts (Faergemann and Baran 2003, Ballesté et al 2003, Tosti et al 2005. Onychomycosis caused by yeast have become increasingly common in medical practice, and have come to represent 75% of all cases in Líbya (Ellabib et al 2002), 59.1% in Rome (Mercantini et al 1996, 49.1% in Rio de Janeiro (Araujo et al 2003), and46.3% in Maringá-PR, Brazil (Souza et al 2007).…”

Dermatophytosis: a 16-year retrospective study in a metropolitan area in southern Brazil

“…The prevalence of superficial fungal infections is highly variable, since it depends on climatic parameters such as humidity and temperature, and on each patients' characteristics such as age, gender, predisposition to diseases, anatomical site of lesion, socioeconomic status, and occupation [5]. Dermatophytoses affect approximately 40% of the world's population, and nail infections represent 18%-40% of the onychopathies [6], representing a public health problem.…”

Onychomycosis - a kórokozók fajspektruma és terápia

“…Egyes felmérések szerint a körömeltérések több mint feléért gombafertôzések felelôsek (1). Az onychomycosis nem csupán kozmetikai probléma, diszkomfort érzés mellett súlyos esetben bakteriális felülfertôzôdés (erysipelas, cellulitis, phlegmone) rizikóját is fokozza (2).…”