A survey on acute kidney injury in severely and critically ill COVID-19 patients without chronic kidney disease.

Background: Research has shown that acute kidney injury (AKI) has a noticeable incidence in critically ill patients with coronavirus disease 2019 (COVID-19). Patients with prior renal insufficiency are particularly susceptible to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), due to their immune dysfunction. However, most patients with COVID-19 do not have a history of kidney dysfunction, and few studies have focused on the incidence of AKI among COVID-19 patients without chronic kidney disease (CKD). In this study, we aimed to investigate the occurrence of AKI in severely and critically ill COVID-19 patients, with a particular focus on those without a CKD history.

Methods: A single-center retrospective study of 96 patients with COVID-19 in China between February 7 and March 3, 2020 was conducted. All patients were diagnosed by nucleic acid test (NAT) for SARS-CoV-2. Enrolled patients were divided into the severely or critically ill group according to the defined criteria. Patients' epidemiological, clinical, and laboratory characteristics, along with their treatment information, were collected from the medical history system. The occurrence of AKI was compared between the severe and critical patients, and between patients with or without a history of CKD. The diagnostic criteria for AKI included an increase in the serum creatinine level to ≥1.5-fold the level at baseline within 7 days according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines. Renal outcomes were defined as AKI or non-AKI.

Results: Four patients (4.2%) developed AKI, all of whom were in the critically ill group, and 3 (75%) of whom died. Out of the 90 severely and critically ill COVID-19 patients without CKD, 3 (3.3%) patients developed AKI; out of the 6 patients with CKD, 1 (16.7%) patient developed AKI. Age, disease severity, procalcitonin, C-reactive protein, and interleukin-6 were correlated with AKI onset in severely and critically ill COVID-19 patients, while lymphocyte count and estimated glomerular filtration rate at admission were inversely related to the development of AKI.

Conclusions: Only 3.3% of severely and critically ill COVID-19 patients without CKD in our research cohort developed AKI. Critically ill patients may be more susceptible to AKI than severely ill patients.