kidney failure

Kidney failure has many possible causes. Some lead to a rapid decline in kidney function ( acute kidney injury, also called acute renal failure). Others lead to a gradual decline in kidney function ( chronic kidney disease, also called chronic renal failure). In addition to the kidneys being unable to filter metabolic waste products (such as creatinine and urea nitrogen) from the blood, the kidneys are less able to control the amount and distribution of water in the body ( fluid balance) and the levels of electrolytes (sodium, potassium, calcium, phosphate) and acid in the blood.

When kidney failure has lasted for some time, blood pressure often rises. The kidneys lose their ability to produce sufficient amounts of a hormone (erythropoietin) that stimulates the formation of new red blood cells, resulting in a low red blood cell count ( anemia). The kidneys also lose their ability to produce sufficient calcitriol (the active form of vitamin D), which is vital to bone health. In children, kidney failure affects the growth of bones. In both children and adults, kidney failure can lead to weaker, abnormal bones.

Although kidney function can decline in people of all ages, both acute kidney injury and chronic kidney disease are more common in older than in younger people. Many disorders that cause a decline in kidney function can be treated, and kidney function may recover. The availability of dialysis and kidney transplantation has transformed kidney failure from a fatal disease to one that is manageable.

Early stage kidney failure often doesn’t cause noticeable symptoms. According to the Centers for Disease Control and Prevention (CDC)Trusted Source, as many as 90 percent of people with chronic kidney disease don’t know they have it.

As kidney disease progresses, possible symptoms may include:

a reduced amount of urine

swelling of your legs, ankles, and feet from retention of fluids caused by the failure of the kidneys to eliminate water waste

unexplained shortness of breath

excessive drowsiness or fatigue

persistent nausea

confusion

pain or pressure in your chest

seizures

coma

Kidney failure can be the result of several conditions or causes. According to the National Kidney Foundation, the two most common causes are high blood pressure and diabetes.

People who are most at risk usually have one or more of the following.

Loss of blood flow to the kidneys

A sudden loss of blood flow to your kidneys can prompt kidney failure. Some conditions that cause loss of blood flow to the kidneys include:

heart attack

heart disease

scarring of the liver or liver failure

dehydration

severe burns

allergic reactions

severe infection, such as sepsis

Diabetes.

High blood pressure.

Heart (cardiovascular) disease.

Smoking.

Obesity.

Being Black, Native American or Asian American.

Family history of kidney disease.

Abnormal kidney structure.

Kidney failure can lead to various complications, such as:

Anemia. When your kidneys aren’t working properly, your body may not be able to properly create red blood cells. Anemia is the medical term for a low red blood cell count.

Bone weakness. Damage to your kidneys can disrupt the balance of minerals in your body such as phosphorus and calcium. This imbalance can lead to weakened bones.

Fluid retention. If your kidneys aren’t able to adequately filter water out of your blood, you may be at risk of developing fluid retention, especially in your lower body.

Heart disease. Heart disease can lead to kidney failure, or kidney failure can lead to heart disease. According to a 2018 studyTrusted Source, heart disease is the most common cause of death in people on dialysis.

Hyperkalemia. Kidney failure can lead to hyperkalemia, or elevated potassium levels. In extreme cases, hyperkalemia can lead to heart failure.

Metabolic acidosis. Disrupted kidney function can lead to metabolic acidosis, meaning your bodily fluids contain too much acid. Metabolic acidosis can cause complications such as kidney stones or bone disease.

Secondary complications. Many people with kidney failure develop secondary complications such as:

depression

liver failure

fluid buildup in lungs

gout

nerve damage

skin infections

You can take steps to lower your risk of kidney failure.

Follow directions when taking over-the-counter medications. Taking doses that are too high, even of common drugs like aspirin, can create high toxin levels in a short amount of time. This can overload your kidneys.

Many kidney or urinary tract conditions lead to kidney failure when they’re not properly managed.

You can also help lower your risk of kidney failure by:

maintaining a healthy lifestyle

taking prescribed medications as directed and not taking more medication than is safe

keeping conditions, such as diabetes and high blood pressure, well managed and following your doctor’s advice