Journal of

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Background and Aim: Tinea unguium is a common disease with worldwide distribution most commonly seen in adult patients. Trichophyton rubrum and T. interdigital are the most common causes. The aim of this study was to investigate the frequency of tinea unguium causative agents in a referral dermatology hospital in Tehran, Iran. Methods: This cross sectional study was conducted in 2010 and 2011 on clinically suspicious patients for tinea unguium referred to the Mycology Laboratory, Razi Hospital, Tehran, Iran. Samples from 700 patients were examined using direct smear microscopy and culture. Direct microscopic examination of the specimens was carried out using 20% potassium hydroxide solution. The specimens were cultured on Sabourad dextrose agar culture media containing chloramphenicol and cyclohexamid (Scc). For identifying the species of dermatophytes, complementary tests were used. Frequencies and relative frequencies were demonstrated in tables and chi-square and Fisher's exact tests were used to investigate any association between the categorical variables. Results: Of 700 dystrophic nail samples, 53 samples (7.6%) were positive according to both direct examination and culture. Thirty-eight patients were males. The most common clinical type was distal subungual onychomycosis which was observed in 79.2% of cases. The most frequent detected dermatophyte species. was T. interdigital (39.6%) followed by T. rubrum (37.7%). Forty-seven patients had tinea unguium on their toe nails, 4 patients on their finger nails, and 2 patients had it on both finger and toe nails. Nineteen patients had underlying diseases, and the most common underlying disease was cardiovascular disease (26.3%). Conclusion: Tinea unguium is a disease with worldwide distribution and identifying the causative agents and predisposing factors are necessary for better management of the patients.

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Onychomycosis is a nail infection caused by dermatophyte and non-dermatophyte molds and yeasts. The nail involvement is a feature of psoriasis, although skin manifestations are the most principal findings in psoriasis. Onychomycosis and psoriasis are both common disorders in communities. It is possible that in some patients these two diseases are present at the same time. A review was performed using the keywords including nail psoriasis, onychomycoses, dermatophytes, non-dermatophyte molds and yeasts in valid medical databases, such as PubMed, Google scholar, Scopus and Science direct. Articles that were most relevant to the purpose of the study were selected and studied. We investigated the incidence and pathogenic function of fungal agents in causing fungal infections in psoriasis nails.

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Onychomycosis is one of the most common human fungal infections, affecting both fingernails and toenails and accounting for approximately 50% of all chronic nail disorders. It may be caused by various dermatophytes, yeasts (especially Candida spp.), and non-dermatophyte molds. Risk factors include advanced age, underlying conditions such as diabetes, immunosuppression, chronic moisture, and prolonged use of closed footwear. Accurate diagnosis requires clinical examination along with direct microscopy, culture, and, in advanced cases, molecular techniques. Treatment options include topical, systemic, or combined antifungal therapies, chosen based on the infection’s severity, causative agent, and patient status. Due to high recurrence rates, preventive measures and complete treatment follow-up are essential. This review provides a comprehensive overview of the epidemiology, clinical manifestations, etiologic agents, diagnostic methods, and therapeutic approaches to onychomycosis, highlighting current challenges in its management.