Prevalence and clinical characteristics of dermatophytosis in rheumatoid arthritis according to DMARD therapy.

Our primary aim was to evaluate the relationship between dermatophytosis and disease-modifying antirheumatic drug (DMARD) therapy in patients with rheumatoid arthritis (RA). This prospective study was conducted in a rheumatology clinic between September 2024 and March 2025. All participants were examined for cutaneous fungal infections by a dermatologist. The study included 80 patients and 40 immunocompetent healthy controls. The most common clinical form of dermatophytosis was tinea unguium, followed by tinea pedis, in both the RA and control groups. There were no significant differences between the groups with respect to age, body mass index (BMI), or sex. Smoking was more frequent among RA patients compared with controls. Dermatophytosis was found in 56% of RA patients and 40% of controls. There was no statistically significant difference in the prevalence of dermatophytosis between RA patients and controls. Dermatophytosis was found in 55.4% of the csDMARD group and 58.3% of the b/tsDMARDs group. There was no statistically significant difference in the frequency of dermatophytosis between RA patients receiving csDMARDs and b/tsDMARDs. RA patients were also divided into two groups based on the presence of dermatophytosis. There was a statistically significant difference in the frequency of dermatophytosis according to sex between the groups. There was no statistically significant difference in the frequency of dermatophytosis with respect to DAS28, smoking status, age, BMI, cumulative methotrexate and corticosteroid exposure, and medical therapy between the groups. In our study, the most common clinical form of dermatophytosis was tinea unguium in both the RA and control groups. Although the prevalence of dermatophytosis was slightly higher in the RA population than in controls, there was no significant difference in the prevalence of dermatophytosis between the groups. Although an increased risk could not be demonstrated in the present study, further large-scale prospective studies are needed to clarify the potential relationship.