In atheroembolic kidney disease, numerous small pieces of fatty material (atheroemboli) travel from arteries above the kidneys to clog the smallest branches of the renal arteries, causing the kidneys to fail.
Usually atheroemboli occur as a complication of surgery or a procedure on an atherosclerotic aorta.
Symptoms of kidney failure, blue toes, or a lacy purplish discoloration of the skin of the feet and legs may develop.
Removing and analyzing a piece of kidney tissue (biopsy) may be done to confirm the diagnosis.
(See also Overview of Blood Vessel Disorders of the Kidneys.)
Causes of Atheroembolic Kidney Disease
Tiny pieces of hard fatty material adhering to a hardened (atherosclerotic) blood vessel wall, usually the aorta, break off and travel through the bloodstream, becoming emboli (atheroemboli). Some emboli travel to the smallest renal arteries, blocking parts of the kidney’s blood supply. Usually, this process affects both kidneys about equally and at the same time. Atheroemboli also may go to other organs and block blood flow there.
The fatty material may break off spontaneously when there is severe atherosclerosis of the aorta. It more commonly occurs as a complication of surgery or angioplasty or of imaging procedures that involve the aorta, such as arteriography, when pieces of fatty material adhering to the walls of the aorta are unintentionally broken off. Atheroembolic kidney disease is much more common in older people.
Symptoms of Atheroembolic Kidney Disease
Atheroembolic kidney disease may cause acute or slowly progressive inability of the kidneys to filter waste products from the blood (kidney failure). As the duration and severity of kidney failure increase, various symptoms of acute kidney injury may appear, beginning with fatigue, nausea, loss of appetite, itching, and difficulty concentrating. The symptoms reflect disturbances in the muscles, brain, nerves, heart, digestive tract, and skin that result from kidney failure.
Atheroemboli may cause symptoms in other organs. If atheroemboli travel to the arms or legs, such symptoms as blue toes or a lacy purplish discoloration of the skin and even gangrene may result. Pieces of atheroemboli that travel to an eye may cause sudden blindness.
Diagnosis of Atheroembolic Kidney Disease
Blood and urine tests
Sometimes a kidney biopsy
Doctors suspect atheroembolic kidney disease in a person who has blood tests that show a decline in kidney function after a procedure that involved the aorta. Routine urine testing is also done. A kidney biopsy is the best way for doctors to confirm the diagnosis of atheroembolic kidney disease but is usually not necessary. A tissue sample examined with a microscope shows characteristic evidence of fatty material in the smallest arteries. Examination of skin or muscle specimens may also help to establish the diagnosis. Sometimes ultrasonography of the aorta is needed to determine the source of the emboli.
Treatment of Atheroembolic Kidney Disease
Treatment of source of emboli
Treatment of high blood pressure
Sometimes dialysis
In the past, people with atheroembolic kidney disease tended to die within weeks or months. However, more recently, treatment has improved. Most people live at least a year. About half live 4 years or more.
Sometimes the source of the emboli can be treated so new emboli do not form, but no direct treatment to remove existing kidney atheroemboli is available. The treatment is to support the person as well as possible. For example, high blood pressure is treated. Dialysis may be needed during kidney failure, but sometimes the kidneys eventually resume functioning.
More Information
The following English-language resources may be useful. Please note that THE MANUAL is not responsible for the content of these resources.
American Association of Kidney Patients (AAKP): AAKP improves the lives of patients through education, advocacy, and promotion of a sense of community among patients with kidney disease.
American Kidney Fund (AKF): AKF provides information about kidney disease and kidney transplant, needs-based financial assistance to help manage medical expenses, webinars for medical professionals, and opportunities for advocacy.
National Kidney Foundation (NKF): This clearinghouse provides everything from information on the basics of kidney function to access to treatment and support for people with kidney disease, continuing medical education courses, and research opportunities and grant support for medical professionals.
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): General information on kidney diseases, including research discoveries, statistics, and community health and outreach programs.