How COVID-19 Can Affect the Kidneys

Many people are aware that COVID-19 can cause dangerous lung problems. However, COVID-19 can also affect other organs, including the kidneys. If that is the case, patients might need kidney replacement therapies such as dialysis while they are being hospitalized for COVID-19.

Why the Kidneys Are Important

The kidneys perform several important functions. By producing urine, they help regulate fluid in your body, making sure your blood can flow with enough pressure. They also regulate the balance of certain minerals and other substances in your blood. Additionally, the kidneys filter away normal toxins created in the body, passing them safely through your urine.

COVID-19 and the Kidneys

In some people with severe cases of COVID-19, the disease damages the kidneys. Doctors call rapid kidney damage like that “acute kidney injury” or “AKI.”

Much is still unknown about how frequently kidney damage occurs. One study found about 5% of patients hospitalized for COVID-19 developed acute kidney injury, but the rate might be higher. People who developed kidney problems from COVID-19 were also more likely to die than people who did not.

Symptoms of Kidney Damage from COVID-19

In addition to what seem to be the most common symptoms of COVID-19—fever and cough—people experiencing kidney damage are more likely to experience the more serious COVID-19 symptom of difficulty breathing.

Kidney damage itself is unlikely to cause symptoms until it is severe. Once it becomes severe, a person may experience:

• Infrequent urination
• Swelling of extremities
• Nausea
• Vomiting

Causes

Researchers are still learning a lot about how COVID-19 causes kidney damage in some people. They do know that other types of coronaviruses, such as those that caused the Middle East respiratory syndrome (MERS), also have the ability to damage the kidneys. Some potential causes include:

• Direct kidney cell damage from COVID-19
• Cytokine storm: An exaggerated maladaptive immune response that happens in some people with COVID-19
• Dehydration: If someone has been sick from COVID-19 for several days and hasn't been drinking enough

Diagnosis of Kidney Damage from COVID-19

Many people with COVID-19 can manage their symptoms at home. However, if you need to be seen at the hospital, doctors will check you for signs of kidney damage, along with other assessments.

Any kidney damage will be revealed in routine blood work as a component of a basic metabolic panel. This includes values of blood urea nitrogen and creatinine, which give information about how well your kidneys are functioning.

Depending on the situation, other tests may be needed, like an analysis of your urine, kidney imaging, or kidney biopsy.

Treatment

If a person doesn’t have severe kidney damage, medications may provide enough support. For example, diuretics might help get rid of excess fluid that the kidneys aren’t eliminating. Other medications might be used to fix abnormalities in electrolytes, like potassium, that can occur in people with kidney disease.

However, if kidney damage is severe, the patient will probably need support in an intensive care unit (ICU). Medical professionals will closely monitor an individual’s vital signs like blood pressure and the amount of oxygen present in their blood. A person might need to receive intravenous fluids. People not breathing well may need artificial ventilation.

After this support is provided, treatment will include some sort of renal replacement therapy. This type of treatment replaces the normal functions of the kidney by filtering toxins from the blood and regulating electrolytes and fluids.

While people with chronic kidney disease are familiar with the intermittent type of renal replacement therapy—hemodialysis a few times a week—acute kidney injury may call for continuous treatment in the ICU. A machine will perform continuous renal replacement therapy (CRRT), continuously filtering the blood while regulating electrolytes and fluids.

Prognosis

We don’t yet have solid information about how well people recover from kidney damage from COVID-19. The degree of kidney damage is likely to be an important factor. Some people will totally recover from their kidney injury. However, other people may develop long-term kidney problems from this initial damage. (That's generally the case for some people who experience acute kidney injury from non-COVID-19 causes.)

Considerations for People With Chronic Kidney Disease

People living with chronic kidney disease need to take careful precautions during the COVID-19 pandemic. These individuals not only have decreased immune systems due to their kidney disease, but often have additional health conditions placing them at a higher risk of COVID-19 infection, like heart disease. Additionally, people with chronic kidney disease seem to have an increased risk of having severe COVID-19 infections.

The situation is made more complicated by the fact that patients with chronic kidney disease need to receive regular dialysis treatments, making social distancing difficult. Although home dialysis is an option for some individuals, many people get treatments three times a week at special dialysis centers in their community.

Since the beginning of the COVID-19 pandemic, dialysis centers have made changes to help protect individuals from the disease. Patients with confirmed COVID-19 cases or who are thought to have COVID-19 are currently being treated at different times and in different clinic areas than to patients who are not. These facilities are also instructed to screen individuals with potential symptoms, such as fever.

A Word From Verywell

Unfortunately, kidney problems are another possible issue from COVID-19 in people who are critically ill. If you are someone who already has kidney disease, take preventative steps to help keep from getting infected, and plan to get your dialysis treatments as regularly scheduled. Your dialysis treatment center will work hard to keep you safe.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.