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Cortical Necrosis of the Kidneys


Zhiwei Zhang

, MD, Loma Linda University School of Medicine

Reviewed/Revised Mar 2023
Topic Resources

Renal (kidney) cortical necrosis is death of the tissue in the outer part of the kidney (cortex) that results from blockage of the small arteries that supply blood to the cortex and that causes acute kidney injury.

  • Usually the cause is a major, catastrophic disorder that decreases blood pressure.

  • Symptoms may include dark urine, decreased urine volume, fever, and pain in the side of the body.

  • Sometimes an imaging test or tissue analysis (biopsy) is done to confirm the diagnosis.

The Kidneys

Renal cortical necrosis can occur at any age. About 10% of the cases occur in infants and children.

Causes of Cortical Necrosis of the Kidneys

In newborns, more than half of the cases occur after delivery complicated by premature detachment of the placenta. The next most common cause is a bacterial infection of the bloodstream (sepsis Sepsis and Septic Shock Sepsis is a serious bodywide response to bacteremia or another infection plus malfunction or failure of an essential system in the body. Septic shock is life-threatening low blood pressure ... read more ).

Symptoms of Cortical Necrosis of the Kidneys

The urine often becomes red or dark brown because of the presence of blood. Pain along both sides of the lower back may occur. A fever is often present. Changes in blood pressure, including mildly high pressure or even low pressure, are common. Urine flow may slow or stop.

Diagnosis of Cortical Necrosis of the Kidneys

  • Routine blood and urine tests

  • Imaging test

  • Sometimes kidney biopsy

Doctors may have difficulty making a diagnosis of renal cortical necrosis because it may resemble other types of acute kidney injury Acute Kidney Injury Acute kidney injury is a rapid (days to weeks) decline in the kidneys’ ability to filter metabolic waste products from the blood. Causes include conditions that decrease blood flow to the kidneys... read more . Doctors may suspect renal cortical necrosis based on symptoms and the results of routine blood and urine tests in people who have predisposing conditions. The diagnosis is often confirmed with an imaging test such as ultrasonography or computed tomography angiography CT angiography Computed tomography (CT) is a type of medical imaging that combines a series of x-rays to create cross-sectional, detailed images of internal structures. In computed tomography (CT), which used... read more CT angiography (CT angiography). Kidney biopsy Kidney biopsy Site-specific biopsies and cell sampling are also used in the evaluation of people with suspected kidney and urinary tract disorders. (See also Overview of the Urinary Tract.) A kidney biopsy... read more can give doctors the most accurate diagnostic information, but a biopsy involves removing tissue and can cause complications and may be unnecessary if the diagnosis is evident. Thus, a biopsy is not done in most people.

Treatment of Cortical Necrosis of the Kidneys

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.

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