Toenail Changes in Patients with Diabetes Mellitus with and Without Onychomycosis

Diabetes mellitus is a predisposing factor for onychomycosis (OM). A high frequency of nonfungal onychodystrophy (OD) is also alleged, although information on the prevalence of specific nail changes is scant. We evaluated the prevalence and types of nail changes in a cohort of diabetic patients with fungal and nonfungal OD.

During a 6-month period, inpatients with diabetes mellitus were screened for foot and toenail changes. Demographic, social, and clinical data were recorded, as was information concerning foot and toenail care. Fungal infection was confirmed by mycologic examination and by histologic analysis of nail clippings.

Of the 82 patients included, 65 (79.3%) had nail changes, and 34 of these 65 patients (52.3%) were diagnosed as having OM. The most frequently observed nail signs were subungual hyperkeratosis, onycholysis, yellow discoloration, and splinter hemorrhages, each seen in more than 25% of the patients. Tinea pedis and superficial pseudoleukonychia were observed more frequently in the OM group (P < .05). Conversely, prominent metatarsal heads and history of nail trauma were more frequent in patients with nonfungal OD (P < .05).

Physicians who care for diabetic patients should not ignore nail changes. Fungal and nonfungal OD are common and should be addressed in the global evaluation of the feet to help prevent breaks in the skin barrier and subsequent bacterial infections and ulcers.