Background: We sought to determine the frequency of toenail onychomycosis in diabetic patients, to identify the causative agents, and to evaluate the epidemiologic risk factors.
Methods: Data regarding patients’ diabetic characteristics were recorded by the attending internal medicine clinician. Clinical examinations of patients’ toenails were performed by a dermatologist, and specimens were collected from the nails to establish the onycomycotic abnormality. All of the specimens were analyzed by direct microscopy and culture.
Results: Of 321 patients with type 2 diabetes mellitus, clinical onychomycosis was diagnosed in 162; 41 of those diagnoses were confirmed mycologically. Of the isolated fungi, 23 were yeasts and 18 were dermatophytes. Significant correlations were found between the frequency of onychomycosis and retinopathy, neuropathy, obesity, family history, and duration of diabetes. However, no correlation was found with sex, age, educational level, occupation, area of residence, levels of hemoglobin A1c and fasting blood glucose, and nephropathy. The most frequently isolated agents from clinical specimens were yeasts.
Conclusions: Long-term control of glycemia to prevent chronic complications and obesity and to promote education about the importance of foot and nail care should be essential components in preventing onychomycosis and its potential complications, such as secondary foot lesions, in patients with diabetes mellitus. (J Am Podiatr Med Assoc 101(1): 49–54, 2011)