Acute kidney injury in severe pneumonia associated with COVID-19

The clinical and epidemiological features of acute kidney injury in severe and extremely severe pneumonia associated with coronavirus disease-2019 (COVID-19) are considered. An observational prospective study was conducted with the inclusion of 117 patients, including 75 men and 42 women, suffering from severe and extremely severe pneumonia associated with COVID-19, who were treated in the intensive care unit of the 1586th Military Clinical Hospital in 2020–2022. Acute kidney injury was diagnosed in 21 (17.9%) patients (stage 1 in 10, stage 2 in 4, and stage 3 in 7 patients), kidney dysfunction was recorded in 22 (8.8%) patients (serum creatinine was higher than normal, but does not reach the diagnostic criteria of Kidney Disease Improving Global Outcomes). Four patients underwent renal replacement therapy. The probability of kidney damage increases with age (the average age of the patients with acute kidney damage is 65 (58; 71) years, and those without acute kidney damage was 47.5 (41; 55) years; p = 0.0001). Compared with patients without acute kidney injury, patients with acute kidney injury scored higher on the scales NEW (p = 0.000975), SMRT-CO (p = 0.011555), and Sequential Organ Failure Assessment (p = 0.000042). Among those suffering from acute kidney injury, significantly more pronounced manifestations of systemic inflammation were determined (leukocytes, p = 0.047324; platelets, p = 0.001230; ferritin, p = 0.048614; and D-dimer, p = 0.004496). In the general cohort, the mortality rate was 22.2%, whereas a significant intergroup difference in mortality was observed, i.e., 52.4% in patients with acute kidney injury and 15.62% in those without acute kidney injury (Chi-squared criterion, 13.468; p < 0.001). Invasive artificial lung ventilation was performed in 19.66% of the patients, and a significant intergroup difference was identified, with 66.7% in patients with acute kidney injury and 9.38% in patients without acute kidney injury (Chi-squared criterion, 35.810; p < 0.001). The durations of treatment in the intensive care unit in patients with and without acute kidney injury were 9 (7; 14) and 6 (4; 10) days, respectively. After the treatment, all patients with acute kidney injury had fully recovered kidney function upon discharge. In general, acute kidney injury occurs in almost every fifth patient with severe and extremely severe pneumonia associated with COVID-19, aggravates the condition of patients, and increases mortality. The alertness of doctors regarding acute kidney injury and early diagnosis and timely nephroprotective treatment may reduce the possibility of adverse disease outcomes.