An 80-year-old man comes to the physician because of a skin rash on his legs. He also complains of mild fatigue and a poor energy level. He denies chest pain/pressure, orthopnea, or dyspnea with exertion. Two weeks ago, he underwent coronary arteriography for unstable angina and had a stent placed in his right coronary artery. His subsequent hospital course was uncomplicated. His other medical problems include hyperlipidemia, type 2 diabetes mellitus, hypertension, and mild cognitive impairment. His current medications include low-dose aspirin, benazepril, atenolol, clopidogrel, hydrochlorothiazide, rosuvastatin, and glipizide. Clopidogrel was added after the stent placement.
His blood pressure is 144/82 mm Hg and pulse is 72/min. His lungs are clear on auscultation. There is a mottled, lace-like, purplish discoloration of both lower extremities from the mid-thigh downward. His pulses are 1+ bilaterally over the distal lower extremities.
Laboratory results are as follows:

Which of the following is the most likely diagnosis?

Question

An 80-year-old man comes to the physician because of a skin rash on his legs.  He also complains of mild fatigue and a poor energy level.  He denies chest pain/pressure, orthopnea, or dyspnea with exertion.  Two weeks ago, he underwent coronary arteriography for unstable angina and had a stent placed in his right coronary artery.  His subsequent hospital course was uncomplicated.  His other medical problems include hyperlipidemia, type 2 diabetes mellitus, hypertension, and mild cognitive impairment.  His current medications include low-dose aspirin, benazepril, atenolol, clopidogrel, hydrochlorothiazide, rosuvastatin, and glipizide.  Clopidogrel was added after the stent placement.
His blood pressure is 144/82 mm Hg and pulse is 72/min.  His lungs are clear on auscultation.  There is a mottled, lace-like, purplish discoloration of both lower extremities from the mid-thigh downward.  His pulses are 1+ bilaterally over the distal lower extremities.
Laboratory results are as follows:

Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec193a_98fe_9027_853d_0362e303e81b_MD0002_00 This patient's presentation is consistent with renal atheroembolic disease (cholesterol crystal emboli), which usually occurs after manipulation of the aorta or other large arteries in patients with atherosclerotic disease. The existing atherosclerotic plaque usually breaks off and embolizes to multiple small arteries leading to tissue and/or organ ischemia. Diagnosis is suggested by subacute onset of acute kidney injury (AKI), particularly with extrarenal embolic disease such as livedo reticularis and cyanotic toes. A skin or kidney biopsy may be necessary in some patients with an unclear diagnosis. Treatment is largely supportive and directed against secondary prevention of cardiovascular disease with aspirin, statins, blood pressure control, and smoking cessation. (Choice A) Acute interstitial nephritis usually causes fever, rash, and eosinophilia. However, it is usually not associated with extra-renal disease such as livedo reticularis or cyanotic toes. (Choice B) Acute kidney injury due to angiotensin converting enzyme inhibitors usually occurs soon after starting the drug and is not associated with an abnormal urinary sediment, as seen in this patient. (Choice D) Pre-renal azotemia usually presents with a spot urinary sodium concentration < 20 mEq/L and normal urinary sediment. This patient's urinary sodium of 38 mEq/L and abnormal urine sediment makes this less likely. (Choice E) Although this patient is at risk, radiocontrast AKI usually resolves within two weeks and is not associated with eosinophilia and livedo reticularis. Educational objective: Atheroembolic disease usually presents with acute kidney injury after arteriography involving the aorta, and is associated with livedo reticularis and a cyanotic or gangrenous toe. __________ References: The challenge of diagnosing atheroembolic renal disease. Clinical features and prognostic factors. (http://www.ncbi.nlm.nih.gov/pubmed/17606842) Cholesterol embolization: A review of 22 cases in the English literature. (http://www.ncbi.nlm.nih.gov/pubmed/3310742)

An 80-Year-Old Man Comes to the Physician Because of a Skin