Acute tubular necrosis is kidney injury caused by damage to the kidney tubule cells (kidney cells that reabsorb fluid and minerals from urine as it forms).
Common causes are low blood flow to the kidneys (such as caused by low blood pressure), medications that damage the kidneys, and severe bodywide infections.
People have no symptoms unless kidney injury is severe.
Diagnosis is based mainly on the results of laboratory tests.
Treatment is directed at the cause, for example, stopping medications that are damaging the kidneys, giving intravenous fluids to raise blood pressure, and giving antibiotics to treat infection.
Injury to the kidney tubule cells harms the ability of the kidneys to filter the blood. Thus, waste products such as urea and creatinine build up in the bloodstream.
(See also Overview of Kidney Filtering Disorders.)
Causes of Acute Tubular Necrosis
Acute tubular necrosis usually develops only in people who are seriously ill and in the hospital. The most common causes are
An episode of low blood pressure, leading to insufficient blood flowing through the kidneys
Medications that damage the kidneys
Serious bodywide infection (sepsis)
The most common causes of low blood pressure leading to acute tubular necrosis are significant blood loss (due to injury or major surgery), serious burns, serious bodywide infection (sepsis), and pancreatitis.
Sepsis also can directly damage kidney cells, which worsens the effects of the low blood pressure caused by sepsis.
Medicationscontrast nephropathy).
Acute tubular necrosis is more likely to develop in people who are older, are critically ill, or have underlying kidney disorders, diabetes, or both.
Symptoms of Acute Tubular Necrosis
People with acute tubular necrosis usually have no symptoms. However, if the condition is severe, kidney failure (loss of most kidney function) develops and people's urine output drops below normal. If kidney failure becomes severe, people may have nausea and vomiting, become weak, develop involuntary muscle spasms, and become confused.
Diagnosis of Acute Tubular Necrosis
Blood and urine tests
Doctors usually first suspect the disorder when blood tests show signs of kidney injury in people who have been exposed to a possible trigger, such as major surgery, an episode of low blood pressure, or a medication that can damage the kidneys. Similar findings can occur in people who are dehydrated, so doctors use other blood tests and urine tests to diagnose acute tubular necrosis.
Treatment of Acute Tubular Necrosis
Supportive care
Medications that are damaging to the kidneys are stopped. Doctors also give intravenous fluids as needed to maintain a normal blood flow to the kidneys. Infections and other underlying disorders are treated. Dialysis may be required for people who do not respond to supportive care.
Prognosis for Acute Tubular Necrosis
Outcome depends on correction of the disorder that caused acute tubular necrosis. If that disorder responds rapidly to treatment, kidney function usually returns to normal in 1 to 3 weeks. Prognosis is usually better if people's urine volume exceeds 400 mL (about 13.5 ounces) every 24 hours. People who are more seriously ill, especially those who require care in an intensive care unit, have a higher risk of death.
Prevention of Acute Tubular Necrosis
When a person is very ill, doctors give intravenous fluids and sometimes medications to maintain blood pressure to try to maintain normal blood flow to the kidneys. Medications that are damaging to the kidneys are avoided whenever possible. If such medications are necessary, kidney function is closely monitored. In people with diabetes, blood sugar levels are controlled.
