Prerenal azotemia is an abnormally high level of nitrogen waste products in the blood.
Azotemia - prerenal; Uremia; Renal underperfusion; Acute renal failure - prerenal azotemia
Prerenal azotemia is common, especially in older adults and in people who are in the hospital.
The kidneys filter the blood. They also make urine to remove waste products. When the amount, or pressure, of blood flow through the kidney drops, filtering of the blood also drops. Or it may not occur at all. Waste products stay in the blood. Little or no urine is made, even though the kidney itself is working.
When nitrogen waste products, such as creatinine and urea, build up in the body, the condition is called azotemia. These waste products act as poisons when they build up. They damage tissues and reduce the ability of the organs to function.
Prerenal azotemia is the most common form of kidney failure in hospitalized people. Any condition that reduces blood flow to the kidney may cause it, including:
Conditions in which the heart cannot pump enough blood or pumps blood at a low volume also increase the risk for prerenal azotemia. These conditions include:
It can also be caused by conditions that interrupt blood flow to the kidney, such as:
Prerenal azotemia may have no symptoms. Or, symptoms of the causes of prerenal azotemia may be present.
Symptoms of dehydration may be present and include any of the following:
An examination may show:
The following tests may be done:
The main goal of treatment is to quickly correct the cause before the kidney becomes damaged. People often need to stay in the hospital.
Intravenous (IV) fluids, including blood or blood products, may be used to increase blood volume. After blood volume has been restored, medicines may be used to:
If the person has symptoms of acute kidney failure, treatment will likely include:
Prerenal azotemia can be reversed if the cause can be found and corrected within 24 hours. If the cause is not fixed quickly, damage may occur to the kidney (acute tubular necrosis).
Complications may include:
Go to the emergency room or call the local emergency number (such as 911) if you have symptoms of prerenal azotemia.
Quickly treating any condition that reduces the volume or force of blood flow through the kidneys may help prevent prerenal azotemia.
Haseley L, Jefferson JA. Pathophysiology and etiology of acute kidney injury. In: Feehally J, Floege J, Tonelli M, Johnson RJ, eds. Comprehensive Clinical Nephrology. 6th ed. Philadelphia, PA: Elsevier; 2019:chap 66.
Okusa MD, Portilla D. Pathophysiology of acute kidney injury. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 28.
Wolfson AB. Renal failure. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 87.
Reviewed By: Walead Latif, MD, Nephrologist and Clinical Associate Professor, Rutgers Medical School, Newark, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.