Case fatality rate among COVID-19 patients treated with acute kidney replacement therapy.

INTRODUCTION: Acute kidney injury (AKI) is a frequent complication of severe COVID-19 and is associated with high case fatality rate (CFR). However, there is scarcity of data referring to the CFR of AKI patients that underwent kidney replacement therapy (KRT) in Brazil. The main objective of this study was to describe the CFR of critically ill COVID-19 patients treated with acute kidney replacement therapy (AKRT).

METHODS: Retrospective descriptive cohort study. We included all patients treated with AKRT at an intensive care unit in a single tertiary hospital over a 15-month period. We excluded patients under the age of 18 years, patients with chronic kidney disease on maintenance dialysis, and cases in which AKI preceded COVID-19 infection.

RESULTS: A total of 100 out of 1479 (6.7%) hospitalized COVID-19 patients were enrolled in this study. The median age was 74.5 years (IQR 64 - 82) and 59% were male. Hypertension (76%) and diabetes mellitus (56%) were common. At the first KRT prescription, 85% of the patients were on invasive mechanical ventilation and 71% were using vasoactive drugs. Continuous veno-venous hemodiafiltration (CVVHDF) was the preferred KRT modality (82%). CFR was 93% and 81 out of 93 deaths (87%) occurred within the first 10 days of KRT onset.

CONCLUSION: AKRT in hospitalized COVID-19 patients resulted in a CFR of 93%. Patients treated with AKRT were typically older, critically ill, and most died within 10 days of diagnosis. Better strategies to address this issue are urgently needed.