Diabetes is characterized by an increased rate of serum glucose due to defects in insulin secretion, insulin action or both conditions. Glucose excesses can lead to extended cellular damage, with the consequence of several infectious and non-infectious skin disorders. The aim of the present study was to evaluate the toenail onychomycosis incidence in diabetic patients and healthy ones. The non-interventional, retrospective study was performed at the mycology laboratory of the University hospital "Policlinico-San Marco" in Catania, Italy, for over one year. Nail clippings were collected to perform microscopic and cultural exams, which allowed for the identification of fungal aetiological agents. A total of 715 patients (47 diabetic and 668 non-diabetic patients) were enrolled. In diabetic patients, dermatophytes were the most common cultural isolates (50%), followed by yeasts and moulds in 30.8% and 19.2%, respectively. In non-diabetic patients, the distribution of dermatophytes, yeasts and non-dermatophytic moulds was 67.4%, 5.3% and 27.3%, respectively. According to our results, diabetic patients are more predisposed to nail fungal infection. Our data suggest that dermatological follow-ups should always be performed for diabetic patients. All skin and nail disorders should be carefully monitored to perform a diagnostic confirmation and correct management of diabetic patients.
Keywords: dermatophytes; diabetes; fungal nail infections; onychomycosis.