Uremia

What is uremia?

Uremia is a dangerous condition that occurs when waste products associated with decreased kidney function build up in your blood. Uremia means “urine in the blood” and refers to the effects of the waste product accumulation. It affects the entire body.

Uremia most often occurs due to chronic kidney disease (CKD) that may lead to end-stage renal (kidney) disease (ESKD), but can also occur quickly leading to acute kidney injury and failure (AKI) that is potentially reversible. Uremia may cause serious health complications such as fluid accumulation, electrolyte, hormone and metabolic problems. Left untreated, uremia is usually fatal and was always so before dialysis and transplantation were available.

Who is at risk for uremia?

People with CKD are at the highest risk for uremia. CKD may be due to disease within the kidneys or more generalized disease. In the United States CKD is most often a result of:

• Diabetes mellitus.
• High blood pressure.
• Glomerulonephritis (GN) (damage to the filters in the kidneys).
• Polycystic kidney disease (PKD) (caused by cysts, or fluid-filled sacs, in or around the kidneys).

What causes uremia?

Healthy kidneys filter waste and fluids from your body through the urine. Kidneys help maintain normal levels of acids, electrolytes and hormones such as Vitamin D and erythropoietin (EPO). Damaged kidneys don’t work well, allowing multiple toxins to build up in your blood. Most people feel sick when kidney function is less than 15% (15 ml/min) of normal and need to start dialysis when function is less than 10% (10 ml/min) of normal.Lab studies monitor chemicals that are elevated in uremia but not necessarily causative:

• Creatinine (waste product produced in muscle and in dietary protein).
• Urea (waste product formed in the liver as protein is broken down).
• Estimation of overall kidney function using a formula ( eGFR - ml/min).
• Stage of CKD from 1 to 5 based on eGFR data from the National Kidney Foundation with dialysis usually starting at Stage 5.

What are the symptoms of uremia?

Symptoms of uremia include:

• Cognitive dysfunction (problems with thinking and remembering).
• Fatigue.
• Shortness of breath from fluid accumulation.
• Loss of appetite.
• Muscle cramps.
• Nausea and vomiting.
• Itching.
• Unexplained weight loss.

In very severe instances, symptoms may include uremic fetor (a urine-like odor on the breath or metallic taste in the mouth) and uremic frost (yellow-white crystals on the skin due to urea in sweat).

What are the complications of uremia?

Uremia can cause serious complications if it’s not treated. Your body may accumulate excess acid, or hormone and electrolyte imbalances –especially for potassium - that can affect the heart. These problems can affect your metabolism, or your body’s process of converting food to energy.The buildup of toxins in your blood can also cause blood vessels to calcify (harden). Calcification leads to bone, muscle, and heart and blood vessel problems.Other complications of uremia may include:

• Acidosis (too much acid in your blood).
• Anemia (too few healthy red blood cells).
• High blood pressure.
• Hyperkalemia (too much potassium in your blood).
• Hyperparathyroidism (too much calcium and phosphorus in your blood leading to elevated parathyroid hormone levels and bone abnormalities).
• Hypothyroidism (underactive thyroid).
• Infertility (inability to get pregnant).
• Malnutrition (lack of nutrients in your body).'

Additional complications of uremia may include:

• Pulmonary edema (fluid in your lungs).
• Defective platelet function and blood clotting leading to bleeding
• Uremic encephalopathy (decreased brain function due to toxin buildup).
• Angina (chest pain).
• Atherosclerosis (hardened arteries).
• Heart failure.
• Heart valve disease.
• Pericardial effusion (fluid around your heart).
• Stroke.

How is uremia diagnosed?

Your healthcare provider:

• Evaluates your symptoms.
• Performs a physical exam.
• Reviews your health history, especially your kidney health and your family history.
• Reviews the lab tests mentioned above. Creatinine and BUN blood tests help your provider confirm a diagnosis of uremia. These tests check your blood for high levels of waste products. They also used to estimate your glomerular filtration rate (eGFR). This rate measures your kidney function.

A kidney ultrasound checks the shape and size of your kidneys and looks for scarring. An ultrasound can also detect kidney blockages, such as kidney stones, or injuries. Additional tests may be needed in certain situations

How is uremia treated?

Dialysis (a procedure to clean the blood) is the most common treatment for uremia. There are two kinds of dialysis. Hemodialysis uses a machine to filter blood outside the body. Peritoneal dialysis uses the lining of your belly and a special fluid to filter blood.

You may need a kidney transplant if uremia is the result of end-stage renal (kidney) failure. A transplant replaces the failing kidney with a donor kidney from either a living or deceased donor.

Your healthcare provider may recommend iron supplementation for anemia, replacement of EPO, calcium and Vitamin D supplements, phosphorus binders taken with meals to prevent bone loss due to hyperparathyroidism. Blood pressure needs to be controlled and any risks for heart disease need to be addressed. Other underlying medical problems must also be managed.

Are there foods or medications I should avoid?

Talk to your healthcare provider or dietician before changing your diet or taking medication or supplements. Certain medications need to be adjusted or avoided and your healthcare provider can assist you in making safe choices. A generally good diet with low sodium and potassium intake is most often used. People with uremia need to be careful about their intake of potassium, phosphate, sodium and protein.

How can I prevent uremia?

People with end-stage kidney disease should have regular dialysis to keep toxins under control. If you have chronic kidney disease, you may be able to prevent or delay disease progression by:

• Controlling your blood pressure, diabetes or other medical problems.
• Taking your prescribed medications.
• Avoiding medications that may further damage your kidneys.
• Eating a heart healthy diet.
• Exercising.
• Maintaining a healthy weight.
• Quitting smoking.

What is the outlook for people with uremia?

Uremia usually requires dialysis and careful monitoring. Severe uremia can lead to coma or death. The most common health complication in people with uremia is heart disease.

When should I contact my healthcare provider about uremia?

Uremia can be a medical emergency. Seek help if you or someone else with kidney issues shows signs of:

• Abnormal behavior.
• Chest pain.
• Cognitive dysfunction.
• Confusion.
• Difficulty breathing.
• Disorientation (not knowing where you are).
• Drowsiness.
• Extreme fatigue.
• Nausea and vomiting.

A note from Cleveland Clinic

Uremia is the result of toxins building up in your blood. It’s a sign of severe kidney dysfunction such as end-stage renal disease. Uremia is a serious medical condition. It can cause hormone imbalances, metabolic problems and even death. Medication can ease some symptoms of uremia. But someone with uremia needs ongoing dialysis or kidney transplant surgery.