COVID-19 Symptom: Kidney Pain
Written by Ada’s Medical Knowledge Team
- Kidney pain with COVID can be related to kidney damage
- Kidney damage is a serious and life-threatening complication that could arise from severe COVID-19
- The kidneys play a crucial role in filtering and balancing the blood, maintaining homeostasis, and regulating many important functions in the body
- Some signs of kidney damage from COVID include decreased urine output, swelling in the legs, ankles, and feet, and breathlessness
- Treatment for COVID kidney may include medications or even dialysis
The SARS-CoV-2 virus, responsible for causing COVID-19, can potentially cause severe and lasting damage to the lungs and other vital organs such as the kidneys. Kidney damage is often associated with severe cases of COVID. Signs of kidney damage and problems in patients with COVID-19 include high levels of protein or blood in the urine and abnormal blood work. The impact of COVID-19 on the kidneys is complex and multifaceted, and its understanding is crucial for the proper management and treatment of COVID-19 patients.
Is kidney pain a symptom of COVID-19?
The kidneys are vital organs that perform several functions that maintain your overall health in the human body. They have several functions, including:
- Waste removal: The kidneys remove waste products and excess fluids from the blood, which are then eliminated from the body as urine.
- Regulation of electrolyte balance: The kidneys regulate the balance of electrolytes, such as sodium, potassium, and phosphorus, in the body.
- Regulation of blood pressure: The kidneys produce hormones that regulate blood pressure and control the production of red blood cells.
- Acid-base balance: The kidneys maintain acid-base balance in the body by controlling the elimination of acids and the production of bicarbonate.
- Vitamin D metabolism: The kidneys convert vitamin D into its active form, which helps regulate calcium and phosphorus levels in the body.
Infections like COVID-19 can cause acute kidney injury (AKI), which can affect the kidneys in the following ways:
- Damage to kidney cells
- Increase in blood clotting
- Possible direct infection of the kidney
Below are some of the most common signs of kidney damage from COVID:
- Reduced urine production, although sometimes urine production remains unchanged
- Accumulation of fluid leading to swelling in the legs, ankles, or feet
- Mental confusion
- Nausea and vomiting
- Lack of strength
- Irregular pulse
- Chest discomfort or tightness
- Seizures or loss of consciousness in severe instances.
If you believe you’re experiencing signs of kidney damage it’s important to contact your doctor right away. Although acute kidney failure can be life-threatening and requires immediate medical intervention, it may also be reversible. If you’re in good overall health, it’s possible to recover normal kidney function.
What causes kidney pain with COVID?
The relationship between COVID-19 and the kidneys is complex and still being studied by doctors and researchers. Some of the theories being investigated include: 1
- Kidney cell targeting: The virus may infect the cells of the kidneys, as the cells have receptors that allow the virus to attach and invade, potentially causing damage to the tissue. This is similar to what has been observed in the lungs and heart. (Read more about heart palpitation and Covid-19 here).
- Oxygen deprivation: In severe COVID-19 cases, patients may experience abnormally low levels of oxygen in the blood, which can lead to kidney malfunction. This is often due to pneumonia.
- Cytokine storms: The body's extreme immune response to the virus can lead to a cytokine storm (cytokine is a cell signaling substance), where a sudden influx of cytokines causes severe inflammation. While trying to fight the infection, this reaction can also destroy healthy tissue, including that of the kidneys.
- Blood clotting: COVID-19 can cause small clots to form in the bloodstream, which can clog the smallest blood vessels in the kidneys and impair their ability to filter toxins, excess water, and waste products from the body.
How long can COVID kidney pain last?
The impact of COVID-19 on the kidneys is not limited to the acute phase of the illness. COVID-19 patients who recover from the acute phase may still experience long-term kidney problems. The incidence of kidney pain COVID is especially high in people who have been hospitalized due to the COVID-19 virus. In one study, 35% of patients still had reduced kidney function 6 months after COVID-19 hospitalization. 2
Some patients may develop chronic kidney disease (CKD), which is a gradual decline in kidney function over time. The incidence of CKD in COVID-19 patients is not well understood, but it’s believed to be higher compared to the general population.
How can you treat COVID kidney pain?
If you suspect that you might have COVID kidney failure, your doctor will conduct a full medical history and physical examination. The following tests might also be utilized: 3
- 24-hour urine output measurement: Keeping track of your urine output over a 24-hour period can aid your doctor in determining the reason for your kidney failure.
- Urinalysis: Examining a urine sample can uncover irregularities that may indicate kidney failure.
- Blood tests: Analyzing your blood may show rapid increases in the levels of urea and creatinine, indicators of kidney function.
- Imaging tests: Diagnostic imaging such as ultrasound and CT scans may be employed to visualize your kidneys.
- Kidney tissue biopsy: In some cases, your doctor may advise a kidney biopsy, which involves removing a small piece of kidney tissue for laboratory analysis. The biopsy is performed by inserting a needle through the skin and into the kidney to obtain the sample.
If kidney failure is suspected, you'll likely need to be hospitalized. You may undergo the following treatments depending on how COVID affects your kidneys:
- Medications to balance fluid levels in the blood. If your acute kidney failure is due to a lack of fluid in your blood, your doctor may suggest receiving IV fluids. On the other hand, if you have too much fluid, leading to swollen limbs, diuretics may be prescribed to eliminate the extra fluid.
- Medications to regulate potassium in the blood. If your kidneys are not effectively filtering potassium from your blood, your doctor may prescribe calcium, glucose, or sodium polystyrene sulfonate to prevent elevated potassium levels in your blood. High potassium levels can cause dangerous heart arrhythmias and muscle weakness.
- Medications to restore calcium levels in the blood. If your calcium levels in the blood become too low, your doctor may recommend receiving an infusion of calcium.
- Dialysis to clean toxins from the blood. If toxins build up in your blood, temporary hemodialysis, commonly referred to as simply dialysis, may be necessary to remove the toxins and excess fluid while your kidneys recover. Dialysis can also help remove extra potassium. During the procedure, a machine removes your blood, filters out waste through an artificial kidney (dialyzer), and returns the purified blood to your body.
If you have recovered from COVID-19 and experienced AKI, make sure to have regular check-ups with your doctor or a nephrologist, as there is a higher chance of developing chronic kidney disease. Additionally, if you had blood and/or protein in your urine while you had COVID, you should be closely monitored as there’s an elevated risk of developing chronic kidney disease. 4
Wrapping it up
The impact of COVID-19 on the kidneys is complex and multifaceted, and its understanding is crucial for the proper management and treatment of COVID-19 patients. Further research is needed to fully understand the mechanisms and long-term effects of COVID-19 on the kidneys and to develop effective strategies for preventing and managing kidney damage in COVID-19 patients.
Q: Can mild COVID cause kidney problems?
A: Yes, even mild COVID-19 infections can lead to kidney problems, particularly in individuals with pre-existing kidney disease or other underlying health conditions. COVID-19 can cause a variety of complications throughout the body, including in the kidneys,
Q: Can COVID make my kidneys hurt?
A: COVID-19 can cause a wide range of symptoms, including some that are related to the kidneys. COVID and kidney can also lead to kidney complications, such as acute kidney injury (AKI), which can cause pain and discomfort in the kidneys.
Q: Is kidney pain a COVID symptom?
A: While kidney pain is not a common symptom of COVID-19, some people with COVID-19 may experience pain or discomfort in the kidneys. COVID-19 can cause a wide range of symptoms, including some that are related to the kidneys, such as acute kidney injury (AKI), a sudden and often temporary loss of kidney function or damage.
Q: How does COVID-19 affect the kidneys?
A: Researchers cite several links between kidney pain and COVID. The virus may target kidney cells or cause blood clots to form. Oxygen deprivation can also lead to pain and failure. In addition, an overactive immune response can also damage kidney tissue.
Q: How common is it to have kidney complications due to COVID-19?
A: The frequency of kidney complications due to COVID-19 is not yet completely understood. However, it’s known that COVID-19 can lead to acute kidney injury (AKI). According to some studies, AKI can occur in 3-9% of hospitalized patients with COVID-19, and this risk is higher in patients with pre-existing kidney disease, diabetes, or high blood pressure.