Uremia, Symptoms, Causes, Normal Levels & Treatment

Uremia is the accumulation of urea in the blood, a toxic waste product normally filtered and removed by the kidneys. This buildup leads to symptoms such as nausea, vomiting, fatigue, chest pain, shortness of breath, and mental confusion.

The condition is primarily caused by chronic or end-stage kidney failure, which results in significantly decreased kidney function. As a result, the kidneys lose their ability to filter blood effectively.

However, blood urea levels may also rise slightly in healthy people due to factors like diet, dehydration, or specific metabolic processes. Consequently, a mild increase does not necessarily indicate the presence of an underlying kidney disease.

Main symptoms

The main symptoms of uremia include:

• Nausea and vomiting;

• Fatigue;

• Loss of appetite and weight loss;

• A metallic or bad taste in the mouth;

• Chest pain or heart palpitations;

• Shortness of breath;

• Headache;

• Cramps, muscle weakness, or restless legs;

• Itching;

• Easy bleeding.

Additionally, when urea accumulates in the brain, it can lead to uremic encephalopathy, causing neurological symptoms such as drowsiness, confusion, memory and concentration issues, seizures, or coma.

Excess urea is toxic to the body and affects circulation and various organs, including the brain, heart, muscles, and lungs. Therefore, it is essential to consult a primary care physician or nephrologist as soon as the first signs of uremia appear.

Confirming a diagnosis

A primary care physician or nephrologist diagnoses uremia by evaluating symptoms, medical history, and physical examination results. They will also confirm the diagnosis through direct blood urea measurement or, more commonly, the blood urea nitrogen (BUN) test, both of which will show elevated levels.

In addition, the doctor generally orders other panels to check levels of hemoglobin, calcium, phosphate, parathyroid hormone, albumin, potassium, and bicarbonate, as well as creatinine clearance and urine tests.

Imaging tests such as a renal ultrasound, CT scan, or MRI may be used to evaluate the kidneys, brain, or other organs. In some cases, a kidney biopsy may be required.

Reference values

The typical reference values for urea in the blood are:

• Normal blood urea level: 10 to 40 mg/dL;

• Critical blood urea level: Greater than 200 mg/dL.

Blood urea levels should always be evaluated by a primary care physician or nephrologist in conjunction with other test results.

Possible causes

High blood urea is mainly caused by advanced chronic kidney failure or acute kidney injury involving rapid loss of kidney function.

However, in healthy individuals, urea levels can be slightly elevated due to factors such as dietary habits (high protein intake), a sedentary lifestyle, dehydration, or individual metabolism. This does not necessarily mean kidney disease is present.

Treatment options

Treatment for uremia must be guided by a nephrologist or primary care physician. It typically involves dialysis, a procedure that filters the blood much like a kidney would to remove accumulated toxins, and should be started as soon as possible.

Initially, hemodialysis is the most common method as it quickly cleans the blood and removes toxic substances. However, the doctor may evaluate whether peritoneal dialysis is a suitable option in certain cases.

Depending on the underlying cause, a kidney transplant may be recommended. A new kidney can restore proper blood filtration and eliminate accumulated toxins.

It is also important to maintain healthy habits to prevent kidney failure from worsening. This includes exercising, drinking the amount of water recommended by a nephrologist, and following a balanced diet that controls the intake of protein, sodium, potassium, and phosphorus.

Possible complications

Uremia can lead to complications such as:

• Increased skin pigmentation;

• Intense itching;

• Pericarditis (inflammation of the heart lining);

• Pericardial effusion (fluid around the heart);

• Pulmonary edema (fluid in the lungs);

• Cardiovascular disease or heart valve calcification;

• Electrolyte imbalances.

Furthermore, high urea levels can result in uremic encephalopathy or uremic pancreatitis.

Therefore, you should go to the hospital immediately upon noticing symptoms of uremia to begin appropriate treatment and avoid life threatening complications