Unilateral Renal Agenesis

Overview


Plain-Language Overview

Unilateral Renal Agenesis is a condition where a person is born with only one kidney instead of two. This affects the urinary system, which is responsible for filtering waste and excess fluids from the blood. The single kidney usually grows larger to compensate for the missing one, allowing most people to live normal lives. However, having only one kidney can increase the risk of high blood pressure and kidney problems later in life. It is often discovered during prenatal ultrasounds or incidentally during imaging for other reasons. People with this condition need monitoring to ensure the healthy kidney continues to function well. Despite the missing kidney, many individuals remain asymptomatic and maintain good health.

Clinical Definition

Unilateral Renal Agenesis is a congenital anomaly characterized by the complete absence of one kidney due to failure of the metanephric blastema or ureteric bud to develop during embryogenesis. This results in a solitary functioning kidney that undergoes compensatory hypertrophy. The condition is usually sporadic but can be associated with genetic mutations affecting renal development pathways such as RET or PAX2. Clinically, it is significant because the solitary kidney is at risk for hyperfiltration injury, leading to proteinuria, hypertension, and eventual chronic kidney disease. It may be isolated or part of syndromes involving other genitourinary malformations. Diagnosis is important for monitoring renal function and preventing long-term complications.

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