New Study Strongly Links COVID-19 to Acute Kidney Injury (AKI)

New Study Strongly Links COVID-19 to Acute Kidney Injury (AKI)

There is mounting evidence that COVID-19 not only damages the lungs, but also the kidneys, resulting in emergency dialysis. The first large scale study from New York City suggests that more than a third of hospitalized patients suffered kidney damage.

Earlier studies from China first pointed to a possible link between COVID-19 and acute kidney injury (AKI), a sudden episode of kidney damage. Doctors in New York City then started reporting a severe spike in COVID-19 cases requiring dialysis. In response to this need, Fresenius Medical Care North America (FMCNA) rushed NxStage machines and supplies into New York City hospitals to support the skyrocketing demand.

The new study by the Feinstein Institutes for Medical Research and published in Kidney International is confirming these initial reports. By examining the electronic health records (EHR) of 5,449 hospitalized COVID-19 patients in New York-based hospitals, researchers determined that 36.6 percent (1,993 patients) developed AKI.

According to the study, patients with respiratory failure were most likely to develop AKI, with 89.7 percent of patients on mechanical ventilation developing AKI compared to 21.7 percent of non-ventilated patients. Of the COVID-19 patients with AKI, 14.3 percent required emergency dialysis to remove the body’s waste and toxins.

“Working amidst the COVID-19 epicenter was an experience we will never forget. Nephrologists and the dialysis staff were on the front lines of this battle trying to help every patient we could,” said Dr. Kenar Jhaveri in a press release, a corresponding author of the study. “We hope to learn more about COVID-19-related AKI in the coming weeks, and that by sharing what we have learned from our patients, other doctors and their patients can benefit.”

Renal involvement with viral infections is not unusual, and nephrologists say this includes dengue, hepatitis B and C, and Ebola, among others. How SARS-CoV-2, the virus that causes COVID-19, is attacking the kidneys is still being studied.

“There are clearly viral particles seen in the kidneys of patients infected with COVID-19,” said Dr. Jeffrey Hymes, senior vice president for scientific and clinical affairs at FMCNA. “It is difficult, however, to determine whether the AKI seen in these very ill patients is due to the virus or the body’s response and inflammatory storm.”

Some studies, including one recently published in the Journal of the American Society of Nephrology, have suggested that the kidneys may be injured when the coronavirus binds to a protein called the angiotensin-converting enzyme 2 (ACE2). This enzyme is prevalent in the kidneys, but it can vary among individuals and those in different regions which could account for the higher incidence in the United States.

“Volume depletion also seems to be frequent in COVID-19 patients, which along with hypoxemia and cytokine storm, can damage cells in the kidneys,” said Dr. Hymes. “We are also seeing reports of increased clotting of blood lines and filters during hospital treatment with dialysis, requiring more aggressive anticoagulation.”

While more information is needed to better understand how this novel coronavirus is impacting the kidneys, a recent emergency use authorization by the FDA will help get more dialysis equipment and supplies into hospitals treating these patients with AKI.