Acute kidney injury and progression to CKD [19]. (a) Conceptual model of acute kidney injury (AKI). (b) Natural history of AKI. Patients who develop AKI may experience (1) complete recovery of renal function, (2) development of progressive chronic kidney disease (CKD), (3) exacerbation of the rate of progression of preexisting CKD, or (4) irreversible loss of kidney function and evolve into ESRD.
