Acute Kidney Injury: Edema and Creatinine

Dr. Haimchand Barran
MMSc Internal Medicine/Infectious Diseases
Fellowship — Nephrology
Nephrology Department – GPHC

As mentioned before, some patients with COVID-19 have displayed kidney damage through acute kidney injury (AKI), mild proteinuria (protein in the urine), hematuria (blood in the urine), or slight elevation in creatinine (blood marker testing for kidney function). Another health issue can be edema.

Edema is swelling caused by excess fluid trapped in your body’s tissues. Although edema can affect any part of your body, you may notice it more in your hands, arms, feet, ankles and legs. Edema can be the result of medication, pregnancy or an underlying disease — often congestive heart failure, kidney disease or cirrhosis of the liver.
Edema associated with kidney disease usually occurs in your legs and around your eyes. Damage to the tiny, filtering blood vessels in your kidneys can result in nephrotic syndrome.
In nephrotic syndrome (a special type of kidney disease in which you lose large amounts of protein in the urine), this declining level of protein (albumin) in your blood can lead to fluid accumulation and edema.
Signs of edema include swelling or puffiness of the tissue directly under your skin, especially in your legs or arms; stretched or shiny skin; skin that retains a dimple (pits), after being pressed for several seconds; and increased abdominal size.
Make an appointment to see your doctor if you have swelling, stretched or shiny skin, or skin that retains a dimple after being pressed (pitting). See your doctor immediately if you experience shortness of breath, difficulty breathing or chest pain.
These can be signs of pulmonary edema (fluid in the lung), which requires prompt treatment. If you’ve been sitting for a prolonged period, such as on a long flight, and you develop leg pain and swelling that won’t go away, call your doctor. Persistent leg pain and swelling can indicate a blood clot deep in your vein, referred to as deep vein thrombosis (DVT).

A creatinine test reveals important information about your kidneys. Creatinine is a chemical waste product that’s produced by your muscle metabolism and to a smaller extent by eating meat.
Healthy kidneys filter creatinine and other waste products from your blood. The filtered waste products leave your body in your urine. If your kidneys aren’t functioning properly, an increased level of creatinine may accumulate in your blood.
A serum creatinine test measures the level of creatinine in your blood and provides an estimate of how well your kidneys filter (glomerular filtration rate). A creatinine urine test can measure creatinine in your urine.
How often you need creatinine tests depends on any underlying conditions and your risk of kidney damage. For example, if you have Type I or Type II diabetes, your doctor may recommend a creatinine test at least once a year. If you have kidney disease, your doctor may recommend creatinine tests at regular intervals to monitor your condition.
If you have an illness that may affect your kidneys — such as high blood pressure or diabetes — or you’re taking medication that may affect your kidneys, your doctor may recommend creatinine tests.
People with kidney disease and other severe chronic medical conditions are at higher risk for more severe illness. People on dialysis can have weaker immune systems, making it harder to fight infections.
However, it is important to know that kidney patients need to continue with their regularly scheduled dialysis treatments and to take necessary precautions as recommended by their healthcare team.
People with a kidney transplant need to take anti-rejection medicines (also known as immunosuppressive medicines). These medicines work by keeping the immune system less active, which can make it harder to fight infections. It is important to keep taking these medicines.
It is also important to wash hands, maintain good hygiene and follow the recommendations from their healthcare team.

There have been recent reports of non-elderly adults infected with COVID-19 who have developed AKI — sudden loss of kidney function. These adults did not have underlying medical conditions. With proper treatment, including dialysis in severe cases, AKI can be reversible.
AKI, also known as acute renal failure (ARF), is not the same as chronic kidney disease (CKD), which will eventually lead to chronic kidney failure (CKF). Neither CKD or CKF are reversible diseases. Detecting proteins and/or blood in urine labs is an early sign of kidney involvement in people with confirmed COVID-19.
It’s recommended that recovered COVID-19 patients who had an AKI should be seen regularly by a kidney doctor, because their risk of developing chronic kidney disease is higher than others.
COVID-19 patients who did not develop an AKI, but who had blood and/or protein in their urine, should be monitored since they are at increased risk of developing chronic- and end-stage-kidney disease.
Older adults and people with kidney disease or other severe chronic medical conditions seem to be at higher risk for more serious COVID-19 illness. If you are at higher risk of getting very sick from COVID-19, you should stock up on supplies; take everyday precautions to keep space between yourself and others; keep away from others who are sick; limit close contact when in public; wash your hands often; avoid crowds as much as possible; and stay home as much as possible during an outbreak.
If you are on dialysis, you should not miss your treatments. Contact your clinic if you feel sick or have any questions or concerns.
If you have a kidney transplant, it is important to remember to keep taking your anti-rejection medicines, maintain good hygiene and follow the recommendations from your healthcare team.

Article submitted as part of the Ministry of Health’s COVID-19 public information and education programme. For questions, email [email protected]