ACE2 and acute kidney injury: The OR for ICU mortality peaked at the ACE2 concentration of 8.8 ng/mL (OR 1.36, 95% CI 0.69–2.69; Fig 3), and that for AKI peaked at the ACE2 concentration of 12.1 ng/mL (OR 1.74, 95% CI 0.80–3.77; Fig 4).