Snapshot A 56-year-old man presents with lower abdominal pain. His symptoms have progressively worsened over the course of the day. Medical history is significant for benign prostatic hyperplasia on tamsulosin. His blood pressure is 144/106 mmHg (normally, his blood pressure is 120/80 mmHg). On physical examination he has bladder distension. Laboratory testing is significant for a creatinine of 2.4 mg/dL (last serum creatinine was 0.7 mg/dL.) Introduction Clinical definition login to view 3 more bullets Epidemiology login to view 6 more bullets Etiology login to view 11 more bullets Pathogenesis login to view 1 more bullet Prognosis login to view 2 more bullets Presentation Symptoms login to view 5 more bullets Physical exam login to view 3 more bullets Imaging Renal ultrasound login to view 4 more bullets Studies Labs login to view 13 more bullets Studies To Assess For Prerenal, Intrarenal, and Postrenal Acute Kidney Injury (AKI) Studies Prerenal AKI Intrarenal AKI Postrenal AKI Urine osmolality (mOsm/kg) > 500 < 350 < 350 FeNa+ < 1% > 2% < 1% in mild cases> 2% in severe cases Urine Na+ (mEq/L) < 20 > 40 > 40 Serum BUN/Cr > 20:1 < 15:1 Variable Differential Acute gastrointestinal bleeding Rhabdomyolysis Medication-induced impairment of creatinine secretion login to view 3 more bullets Treatment Treatment is dependent on the etiology of AKI and its consequences login to view 3 more bullets Complications Hyperkalemia Metabolic acidosis Uremic encephalopathy and platelet dysfunction Anemia Chronic kidney disease