A 53-year-old man with a history of obesity, obstructive sleep apnea, hypertension, and hypercholesterolemia presents to the clinic complaining of a nonhealing ulcer on his left ankle present for the past month. His blood pressure is 160/78 mmHg.
His physical examination is remarkable for mild bilateral lower leg edema as well as lipodermatosclerosis and hyperpigmentation around the ankles. A mildly tender, superficial ulceration is observed with an irregular pink base above his medial malleolus. His feet and toes are warm, pink, and have 2-second capillary refill and intact sensation. Laboratory tests on this patient include a random blood sugar of 160 mg/dL, creatinine of 1.1 mg/dL, calcium of 10.4 mg/dL, phosphorus of 4.4 mg/dL, and serum intact parathyroid hormone level of 50 pg/mL.
What is the most likely etiology of the ulceration?a. Diabetes mellitus
Chronic venous insufficiency. This patient has no history of neuropathy and has intact sensation, making a neurotrophic ulcer often associated with diabetes unlikely. While his glucose is elevated, inadequate information is provided to make the diagnosis of diabetes mellitus. Bilateral leg edema, hyperpigmentation of the ankles, and the location of the ulcer over the medial malleolus (“gaiter distribution”) are findings consistent with a venous stasis wound. Ulcers secondary to arterial disease are usually painful, involve the toes, and are well circumscribed. The information provided suggests adequate arterial supply. Wounds associated with calciphylaxis may be anywhere. They are usually very painful, involve large areas of skin, and are associated with black eschar formation. These wounds are most often seen in patients with renal impairment and hyperparathyroidism, neither of which is true in this case. Nothing in the clinical vignette is suggestive of a brown recluse spider bite.
Hirsch AT, Haskal ZJ, Hertzer NR, et al. ACC/AHA 2005 practice guidelines for the management of patients with peripheral arterial disease (lower extremity, renal, mesenteric, and abdominal aortic): a collaborative report from the American Association for Vascular Surgery/Society for Vascular Surgery, Society for Cardiovascular Angiography and Interventions, Society for Vascular Medicine and Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of Patients with Peripheral Arterial Disease). Circulation. 2006;21(113):e471–e486.