Patients with diabetes may also develop Ophthalmologic disease unrelated to diabetic retinopathy (eg, cataracts, glaucoma, corneal abrasions, optic neuropathy) Hepatobiliary diseases (eg, cirrhosis, gallstones) Dermatologic disease (eg, tinea infections, lower-extremity ulcers, diabetic dermopathy, necrobiosis lipoidica diabeticorum, diabetic systemic sclerosis, vitiligo, granuloma annulare, acanthosis nigricans [a sign of insulin resistance]) Depression Dementia Other Complications of Diabetes Mellitus Cellulitis (Foot Ulcer) A patient with diabetes often develops microvascular disease, which may impair skin healing, so that even minor breaks in skin integrity can develop into deeper ulcers and easily become infected, particularly in the lower extremities.