Prepared by: Ms. Tabarak Ahmed Turki Al-Azzawi
Introduction:
Urea is a nitrogen-containing compound produced from the breakdown of proteins in the body. It is synthesized in the liver and excreted by the kidneys in the urine. Blood Urea Nitrogen (BUN) levels are important indicators of kidney function. Elevated levels in the blood suggest a dysfunction in waste elimination, which may be due to renal or non-renal causes.
Mechanism of Urea Production in the Body:
When proteins are digested, amino acids are broken down into nitrogenous byproducts. These are then converted in the liver into urea, a non-toxic form of nitrogen. Urea is transported through the blood to the kidneys, where it is excreted in the urine.
Causes of Elevated Urea in the Blood:
Causes can be categorized into three main groups:
1. Pre-renal Causes:
These result from reduced kidney perfusion without intrinsic kidney disease, such as:
Severe dehydration
Hypotension or shock
Congestive heart failure
Acute blood loss or hemorrhage
2. Renal Causes:
These stem from direct kidney diseases or damage, such as:
Acute or chronic kidney failure
Glomerulonephritis
Diabetic nephropathy
Genetic kidney disorders (e.g., polycystic kidney disease)
3. Post-renal Causes:
These are due to obstruction in the urinary tract preventing urea excretion, such as:
Kidney or ureteral stones
Benign prostatic hyperplasia (BPH)
Bladder or urethral tumors
Other Contributing Factors:
A diet high in protein
Upper gastrointestinal bleeding
Use of certain medications (e.g., steroids, diuretics)
Severe physical stress or extensive burns
Diagnosis:
Elevated urea is diagnosed through a simple blood test called BUN (Blood Urea Nitrogen). It is often accompanied by a creatinine test to assess kidney function more accurately.
Normal Blood Urea Levels:
☑️ In adults: Approximately 7–20 mg/dL, though this may vary slightly depending on the laboratory.
Treatment:
Treatment depends on the underlying cause:
Dehydration: Rehydration with fluids
Kidney failure: May require specialized treatment such as dialysis in advanced cases
Urinary obstruction: May require surgical intervention or catheterization
Dietary causes: Reducing protein intake in specific cases
Prevention:
Drink adequate amounts of water
Regularly monitor chronic kidney diseases
Avoid excessive dietary protein
Use painkillers and diuretics cautiously
Conclusion:
Elevated blood urea does not necessarily indicate permanent kidney failure. However, it is a significant biological warning sign indicating an imbalance between urea production and excretion. Accurate diagnosis, correlation with clinical symptoms, and patient history are
essential for identifying the cause and providing proper treatment.
Al-Mustaqbal University the First in Iraq