NPPA and acute kidney injury: prospectively enrolled 341 patients presenting to the emergency department with CAP, and investigated the potential of plasma N-terminal prohormone B-type natriuretic peptide (NT-proBNP), mid-regional pro-atrial natriuretic peptide (MR-proANP) and B-type natriuretic peptide (BNP) levels within the first 48 h to predict early AKI in hospitalized patients with CAP.