Hyperkalemia and hyperphosphatemia refractory to renal replacement therapy (RRT) more frequently occurs in patients with COVID-19 and acute kidney injury (AKI) than in uninfected patients with AKI. Investigators presented the new findings at the American Society of Nephrology’s Kidney Week 2020 Reimagined virtual conference.
Acknowledging anecdotal accounts of an unusual incidence of persistent hyperkalemia and hyperphosphatemia among patients with COVID-19 and AKI, Akanksh Ramanand, MD, of the University of Queensland in New Orleans, Louisiana, and colleagues compared a cohort of 161 patients hospitalized with COVID-19 and AKI with 60 uninfected patients who had AKI during the pre-COVID-19 era. All patients underwent sustained low efficiency dialysis (SLED) and other types of RRT were excluded.
The COVID-19 AKI group had a significantly higher incidence of moderate hyperkalemia (serum potassium 5.5 mEq/L or greater) than the uninfected control group with AKI: 19% vs 14% of SLED days, respectively, the investigators reported. Patients with COVID-19 also had a significantly higher incidence of severe hyperkalemia of 6.5 mEq/L or greater: 33% vs 7% of SLED days, respectively.
The overall rates of hyperphosphatemia (4.5 mg/dL or higher) were similar between the groups (56% vs 53% of SLED days), but the COVID-19 AKI group experienced a significantly higher incidence of severe hyperphosphatemia (defined as serum phosphate greater than 10.0 mg/dL) than the control group: 86% vs 60% of SLED days, respectively.
Serum potassium and serum phosphate correlated with lactate dehydrogenase (LDH), Dr Ramanand’s team reported, and hyperphosphatemia episodes correlated with shorter SLED runs. Intracellular ion release from cell injury due to cytokine ‘storm’ and RRT interruptions may play a role, they noted.
In the study, a significantly higher proportion of the COVID-19 and AKI group were Black race (77% vs 30%) and male (78% vs 61%), respectively. Ischemic acute tubular injury was the presumed cause of AKI in 85% and 82% of the COVID-19 and uninfected AKI groups, respectively.
Ramanand A, Varghese V, Wen Y, Mohamed M, Velez JC. Refractoriness of hyperkalemia and hyperphosphatemia in dialysis-dependent AKI associated with COVID-19. Presented at: Kidney Week 2020 Reimagined; October 19-25, 2020. Poster PO0704.