A 72-year-old man comes to the emergency department due to sudden-onset, severe abdominal pain accompanied by nausea. He has a history of coronary artery disease and recently underwent cardiac angiography. The patient is a current smoker with a 30-pack-year history. After initial evaluation, he undergoes emergency laparotomy. A segment of small intestine is resected. On microscopic examination, there are several large-caliber vessels with needle-shaped cholesterol clefts in their lumens, as shown in the image below. Given these findings, the patient is at highest risk for which of the following complications?

Question

A 72-year-old man comes to the emergency department due to sudden-onset, severe abdominal pain accompanied by nausea.  He has a history of coronary artery disease and recently underwent cardiac angiography.  The patient is a current smoker with a 30-pack-year history.  After initial evaluation, he undergoes emergency laparotomy.  A segment of small intestine is resected.  On microscopic examination, there are several large-caliber vessels with needle-shaped cholesterol clefts in their lumens, as shown in the image below.  Given these findings, the patient is at highest risk for which of the following complications?

Quizplus · Accepted Answer

11ec160b_3a7d_6394_9249_95c512da6c99_MD0001_00 This patient developed acute abdominal pain after recent coronary angiography. Small bowel histology demonstrates needle-shaped intravascular cholesterol clefts, a characteristic finding in atheroembolic disease (ie, cholesterol crystal embolism). Cholesterol is dissolved during tissue processing, leaving empty clefts on histologic evaluation. Atheroembolic disease typically occurs after an invasive vascular procedure (eg, coronary angiography, aortic surgery) in which atherosclerotic plaques on large vessels (eg, aorta) are mechanically dislodged. This leads to showering of cholesterol-rich microemboli into the circulation with resultant obstruction of distal arterioles and tissue ischemia. Clinical manifestations depend on the location of the embolic scatter. Patients frequently develop acute kidney injury due to partial or complete occlusion of the arcuate or interlobular arteries. Other commonly involved organ systems include the skin (eg, blue toe syndrome, livedo reticularis), the gastrointestinal tract (eg, bleeding; intestinal infarction, as in this patient), and the CNS (eg, stroke, amaurosis fugax). (Choice B) Heparin anticoagulants given during angiography can cause heparin-induced thrombocytopenia (HIT), which typically presents with low platelet counts and thrombotic complications. However, the destruction of platelets in HIT is due to immune-mediated platelet aggregation, rather than bone marrow suppression. (Choice C) Gout causes needle-shaped crystals seen on microscopy. However, uric acid crystals are negatively birefringent (not empty clefts) and are located within tophi or synovial fluid. In addition, gout does not cause embolic disease. (Choice D) Pulmonary infarction can also occur in atheroembolic disease; however, this is an extremely rare manifestation and occurs much less commonly than acute kidney injury. (Choice E) Infectious endocarditis also causes embolic showering and can cause both small bowel involvement and septic arthritis. However, endocarditis is more common in drug users, and patients typically develop fever, arthralgias, and night sweats. In addition, bacteria, not cholesterol clefts, would be visualized on microscopic examination. Educational objective: Atheroembolic disease typically occurs after an invasive vascular procedure due to mechanical dislodgement of atherosclerotic plaque, resulting in the showering of cholesterol-rich microemboli into the circulation. Needle-shaped cholesterol clefts in affected vessels are diagnostic. Commonly involved organs include the kidneys (eg, acute kidney injury), skin (eg, blue toe syndrome, livedo reticularis), gastrointestinal tract (eg, bleeding, infarction), and CNS (eg, stroke, amaurosis fugax).

A 72-Year-Old Man Comes to the Emergency Department Due to Sudden-Onset