Dermatological care of the diabetic foot

Approximately 30% of patients with diabetes mellitus will have disease-related dermatological problems. Dry skin can be associated with autonomic neuropathy and may be fragile, promoting bacterial invasion. Any potentially infected 'diabetic foot' must be taken seriously, and non-painful deep sepsis suspected if there is evidence of sensory loss. Consideration should be given to eliminating nasal carriage of staphylococci if recurrent superficial sepsis occurs in the presence of poor diabetic control. Fungal infections, both of skin and nails, are common but usually not serious in the absence of immunosuppression. Treatment with topical antifungals may need to be combined with systemic therapy for successful eradication. Systemic antifungal therapy should be carefully considered as treatment needs to be prolonged and is potentially toxic, particularly in individuals with diabetes mellitus who often have co-morbidities. Varicose eczema should be treated by physical therapies intended to improve venous return and prevent peripheral edema and tissue injury. Allergic dermatitis is commonly associated with topical treatments and other sensitizers. Many reactions are not apparent from history, and patch testing for sensitivity is recommended. There are several diabetes mellitus-specific conditions that dermatologists must be aware of, including, necrobiosis lipoidica diabeticorum, granuloma annulare, diabetic dermopathy (spotted leg syndrome or shin spots), diabetic bullae (bullosis diabeticorum), and limited joint mobility and waxy skin syndrome. Ulceration, due to varying combinations of peripheral vascular disease and sensory neuropathy, is the province of the specialist team dealing with the diabetic foot and should ideally be referred to an appropriate multidisciplinary team.