What is azotemia (elevated blood urea nitrogen and creatinine levels, indicating impaired renal function)?

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From the Guidelines

Azotemia is a condition characterized by the inability of the kidneys to secrete nitrogenous wastes, leading to an accumulation of these substances in the blood, as defined by the American College of Radiology in 2021 1.

Definition and Causes

Azotemia occurs when the kidneys are unable to effectively filter waste products from the bloodstream, resulting in elevated levels of nitrogen-containing compounds, such as urea and creatinine, in the blood. This condition can be classified as prerenal, intrarenal, or postrenal, with common causes including dehydration, heart failure, kidney disease, urinary tract obstruction, and certain medications 1.

Symptoms and Diagnosis

Symptoms of azotemia may not be present in mild cases, but as the condition progresses, patients may experience fatigue, decreased urination, swelling, nausea, and confusion. Diagnosis involves blood tests measuring blood urea nitrogen (BUN) and creatinine levels, as well as urine tests to evaluate kidney function and identify any underlying causes 1.

Treatment and Prognosis

Treatment of azotemia depends on the underlying cause and may include fluid replacement, medication adjustments, treating infections, or relieving urinary obstructions. If left untreated, azotemia can progress to uremia, a more severe condition with toxic effects throughout the body, potentially leading to kidney failure requiring dialysis or transplantation 1.

Key Considerations

It is essential to identify the specific cause of azotemia to provide appropriate treatment, as different causes require different interventions. A thorough history, physical examination, and laboratory analysis are crucial in evaluating patients with azotemia 1.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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