CRP and acute kidney injury: In this prospective, observational, non-interventional, single-center study, we assessed various plasma and urinary biomarkers of kidney injury (NGAL, KIM-1, IL-18); inflammation (IL-6, C-reactive protein [CRP]); and angiotensin-converting enzyme 2 (ACE2) in COVID-19 patients at ED admission, with the aim of correlating them with the outcomes (mortality, AKI).