Diabetes Mellitus (DM) is a risk factor for fungal infections, including onychomycosis. The study aims to determine the prevalence of toenail onychomycosis in diabetic patients and its correlation with associated factors, identify the causative agents and compare the fungal culture findings with the real-time polymerase chain reaction (RT-PCR) findings of diagnosing 6 fungal isolates. A total of 126 diabetic patients were included between November 2020 to June 2021. Nail samples were subjected to potassium hydroxide 20%. Culture was done on Sabouraud dextrose agar medium (SDA), both with and without cycloheximide. Identification of non-dermatophytic molds was based on colony characteristics, colony reverse, cello-tape flag method and slide culture technique. Molecular analysis was done to make sure of the identification of 6 fungal isolates. Out of 126 cases, 106 (84.1%) had toenails onychomycosis. Non-dermatophytic molds (NDM) were the most common isolates 75 (70.8%), followed by yeasts 8 (7.5%) and mixed infections 23 (21.7%). Distal lateral subungual onychomycosis (DLSO) was the most frequent clinical type 90 (85%). Onychomycosis was found to correlate significantly with advancing age, type 2 diabetes, its duration and clinically abnormal nails. However, there was no significant correlation with gender and glycosylated hemoglobin (HbA1C). When the results obtained by RT-PCR were compared with the results obtained by fungal culture, a 100% match of the isolates was found.
