Onychomycosis in patients with nail psoriasis: a point to point discussion

Abstract

Onychomycosis is the most common nail disease and affects large parts of the population. Psoriasis is a frequently encountered skin disorder with nail involvement being found in up to 80% of the patients at some time of the course of the disease. It has been postulated that onychomycosis occurs more frequently in patients with nail psoriasis, but the results of studies in the literature are controversial. Moreover, onychomycosis could exacerbate psoriasis through Koebner phenomenon and the treatment of psoriasis could predispose to onychomycosis. Finally, the differential diagnosis could be a real challenge due to many same clinical signs, the high prevalence and the possible coexistence of the two diseases. This article attempts to enlighten all these different aspects of a very close relationship.

Prevalence of onychomycosis among patients with nail psoriasis who are not receiving immunosuppressive agents: Results of a pilot study

“…Few studies, also examining only nail psoriasis patients found a substantially higher prevalence of onychomycosis among them; it is possible that the inclusion of patients currently being or having recently been treated with immunosuppressive agents can justify the noted difference . The majority of studies examining psoriasis patients with as well as without psoriatic nail lesions have reported a smaller prevalence of onychomycosis than the one found in our study . This discrepancy is possibly attributed to the fact that psoriasis patients with clinically healthy nails seem to be less susceptible to dermatophyte infections of the nail than the general population.…”

“…Although no significant difference was observed between the 2 groups regarding the growth of T. mentagrophytes , C. albicans grew significantly more in psoriatic keratin. The faster growth of psoriatic nails, the presence of anti‐dermatophyte‐acting peptides and the altered structure of nails with psoriatic lesions might be responsible for this phenomenon …”

“…The percentage of psoriasis patients and nail psoriasis patients with onychomycosis varies widely in literature (4.60%‐62% and 8%‐60.58% respectively). Consequently, the prevalence of onychomycosis among psoriasis and nail psoriasis patients has been found equal to, less and greater than that among healthy controls or the general population . The exact nature of the relationship between the two diseases remains, therefore, elusive .…”

“…Consequently, the prevalence of onychomycosis among psoriasis and nail psoriasis patients has been found equal to, less and greater than that among healthy controls or the general population. 13 The exact nature of the relationship between the two diseases remains, therefore, elusive. 13 The purpose of this study is to determine the prevalence of fungal nail infections among patients with psoriatic nail lesions, who are have not undergone treatment with immunosuppressive agents.…”

Variability in Systemic Treatment Efficacy for Onychomycosis: Information That Clinical Studies Do Not Impart to the Office Dermatologist

“…Successful treatment may sometimes eliminate the fungal elements and achieve a mycological cure, but not a clinical cure [4]. In psoriatic patients, several nails could be involved or one nail might have psoriasis alone or psoriasis combined with onychomycosis, while the adjacent nail might be healthy but infected with fungus [15]. …”