A new classification of onychomycosis

Abstract

This new classification of onychomycosis is a development of previous schemes and depends on the recognition of different clinical patterns of nail plate involvement associated with fungal infection as well as histopathology. The main types are distal and lateral subungual onychomycosis, superficial onychomycosis, proximal subungual onychomycosis, endonyx onychomycosis and total dystrophic onychomycosis. In addition, patients may show different combinations of these patterns. The identification of clinical patterns of disease may be useful in defining differences in clinical behaviour, treatment response and associated disease.

Dermatophytosis (Tinea) and Other Superficial Fungal Infections

“…The most common presentation of onychomycosis is distal lateral subungual onychomycosis (DLSO), which presents as a nail with discoloration and varying degrees of hyperkeratosis, onycholysis (separation of nail from nail bed), subungual debris, and thickening [25,26] (Fig. 21.7).…”

“…These presentations may not respond well to therapy. Sometimes, infection may present as superficial white onychomycosis (SWO), proximal subungual onychomycosis (PSO), or endonyx onychomycosis [25,26]. SWO involves infection of the superficial nail plate, showing patches of white discoloration on the nail surface.…”

Can we Prevent Onychomycosis?

“…Candida nail infections may also occur resulting in onycholysis and paronychia. Finally, total dystrophic onychomycosis may be the end result of any subtype [8,9]. The vast majority of infections are of the DLSO variety, and all the medications used to treat onychomycosis are specified for this indication only.…”

Spores, Sporodochia and Fomites in Onychomycosis

“…The distal subungual onychomycosis is the most common clinical type of the disease. Other clinical types include the white superficial onychomycosis, the proximal subungual onychomycosis, the endonyx onychomycosis and the total dystrophic onychomycosis [2]. The different names given to the fungal cells are defined in table 1.…”