Although many people think of Covid as primarily a respiratory disease, the virus that causes this disease is also capable of causing symptoms in many other organ systems throughout the body.
Can Covid affect the kidneys? How do you know if your kidneys have been damaged by Covid?
It’s well-established that Covid can cause damage to the kidneys. In fact, this is very common in people who have severe cases of the disease. Between 28% and 46% of patients who are hospitalized for Covid show evidence of acute kidney injury. Of these, a significant proportion have severe enough kidney damage to require dialysis.
The symptoms of kidney damage from Covid depend on how severe the damage is. In more severe cases, kidney failure can occur, leading to symptoms like:
However, in patients who experience more mild kidney damage, there may not be obvious symptoms. The damage to the kidney might only be detectable on blood and/or urine tests that measure kidney function.
It’s been more than two years since the Covid-19 pandemic began, but we still don’t know everything about the virus. Researchers are still working to understand how SARS-CoV-2 (the virus that causes Covid) affects the body, including the kidneys. There are believed to be a few ways that Covid can cause kidney damage:
In many patients, kidney function does return to normal after they recover from Covid. However, studies have shown that in patients hospitalized for Covid, 35% have not recovered their kidney function at the time of discharge from the hospital.
Because this is a relatively new virus, we don’t yet have good data on the long-term implications of Covid. It’s not yet known how many patients with Covid will go on to develop chronic kidney disease. However, researchers do believe that Covid increases the risk of chronic kidney disease, particularly in patients whose Covid infection is severe.
Mild to moderate kidney damage may not cause any obvious symptoms in most patients. The only way to know for sure whether your kidneys have been damaged is to get a kidney function test. You can visit your doctor for a consultation, and then go to a laboratory to get blood and/or urine samples taken for the test. Another option is to order a home test kit.
Kidney damage is a known side effect of Covid-19, and a significant proportion of people who are hospitalized with Covid show evidence of decreased kidney function.
Blood in the urine can be a sign of kidney damage, whether this occurs due to Covid or another cause (such as high blood pressure or diabetes). Blood in the urine may make it look red, pink, or brown. Patients who have blood in the urine after Covid should have their kidney function tested
While certain kidney conditions, like kidney infections and kidney stones, commonly lead to pain in the area of the kidneys (the mid-back, around the bottom of the ribs), Covid typically doesn’t cause kidney pain. Instead, the kidney damage caused by Covid is more insidious, and may even occur without any obvious symptoms.
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Kidney disease & COVID-19. National Kidney Foundation. https://www.kidney.org/coronavirus/kidney-disease-covid-19. Accessed 27 June 2022.
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