Over 20 years, this study unveils the prevalence of anthropophilic dermatophytes, led by Trichophyton rubrum, offering crucial insights as Ireland's first detailed fungal analysis in a long time.

To conduct a thorough retrospective epidemiological examination of all dermatological mycology tests carried out at University Hospital Limerick spanning a two-decade period.

In this single‐institution review, the mycology lab test outcomes from the Laboratory Information Management System (DXC Technologies) from 2001-2020 were extracted. Specimen types were classified as per the sampling site, and data analysis was assessed using Microsoft Excel.

Overall, 12,951 samples of skin, hair and nails were analyzed. The median age of the patients was 42 years and 57.2% were females. Among the samples, 67% (n = 8633) were nails, 32% were skin scrapings (n = 4118), and 1.5% (200 samples) were hair. Zoophilic dermatophytes were more prevalent in females and individuals under 10 years or between 45 and 70 years (36% and 34% zoophiles, respectively).

However, anthropophiles were predominant across all age and gender categories, with the highest prevalence in the 10 to 20 age group (80% anthropophiles, proportion of dermatophytes). Yeast infections were more common in geriatric patients (29% in those more than 60 years old versus 17% in less than 60 years old, percentage of all fungal positives). Trichophyton rubrum emerged as the most prevalent pathogen, constituting 53% of all detected dermatophytes. It was present in 61% of nail and 34% of skin/hair specimens.

In tinea capitis, Trichophyton tonsurans was the predominant dermatophyte, accounting for 37% of detections. Both organisms, T rubrum and T tonsurans, being anthropophilic, consistently demonstrated augmented prevalence in proportion to all isolates of fungi. As observed from the nail and skin/hair specimens, the proportion of anthropophilic dermatophytes grew from 55% in the first 5 years to 88% in the final 5 years of the total study period. Conversely, yeast detection reduced over the study period.

This study offers a thorough 20-year analysis of fungal cultures from skin, nail, and hair samples in Ireland's Mid-West. Understanding these trends is crucial for pinpointing infection sources, detecting outbreaks, and guiding treatment decisions. Notably, it marks the first detailed fungal analysis in Ireland in over seven years, providing valuable epidemiological insights.