• ACUTE KIDNEY INJURY – 2/2 Pre-renal vs Renal vs Post Renal  
• Ask 4 questions
• New Medications, Procedures
• Vitals
• History suggestive of change in Volume Status i.e decreased PO, Diarrhea etc. 
• Sx and risk factors for Urinary Obstruction
• Tests to order: 
• DO “4 U” TEST: UA with microscopy (look for Casts, Crystals, and Cells), Urine Electrolytes to calculate FeNa, Urine Osmolality, Urine Eosinophil, USG of Kidney (do not do if clinically hypovolemic), FeUrea (if on diuretics) (< 35 % in Prerenal)
• Other Labs:
• Urine Osm: 
• Urine findings associated with acute kidney injury (MKSAP Nephro Table 17)
• Fractional Excretion of Various Solutes in Oliguric Acute Kidney Injury (MKSAP Table 15)
• Rx:
•       Fluid (Pre-renal)                                                                                                                               
•       Foley Cath (if post-renal)
•       Supportive Management, and  -+ Fluid (Renal-Renal)

• Classification
• RIFLE Criteria (2004): Urine Output, and Cr
• AKIN (2007): RIF as stage 1, 2, 3  Acute Kidney Injury Network Criteria for the Classification of Acute Kidney Injury (MKSAP Nephro Table 34)
• Anuric: < 100 cc / 24
• Oliguric <400 cc / 24 hr
• Non-oliguric > 500 cc / 24 hr
• KDIGO Criteira
• Implications:
• Prognosis
• Labs:
• How to prevent AKI: 
• Know the risk factors: CKD, > 75 yr, DM, HTN, HF, Liver disease, Hypotension. 
• Intrinsic Renal Failure
• ATN (Acute Tubular Necrosis)
• AIN (Acute Interstitial Nephritis)
• Causes of Acute Interstitial Nephritis (MKSAP Nephro Table 40)
• Bitter Pills NEJM CPS (Acute Interstitial Nephritis) 2010
• Eosinophiluria and Acute Interstitial Nephritis NEJM 2009
• CIN (Contrast Induced)
•  Approach to the Prevention of Contrast-Induced Nephropathy (MKSAP Nephro Table 39)
• Others (Glomerular Disease, Pigmented Nephropathy, Trombotic Microangiopathy
• Additional References: 
• Diagnostic Criteria for Hepatorenal Syndrome in Cirrhosis (MKSAP Nephro Table 41)

Renal Failure: 
Case 5-2014: Fever, Confusion, Thrombocytopenia, Rash (IE vs TTP vs tick born vs small vessel disease)
Case 3-2014:  Gastrointestinal Symptoms, Anemia,  (RPGN, MPGN, Cryoglobunemia II)
Case 30-2011 (Sclerodermal Renal Crisis)
Case 29-2011 (Plasma-cell myeloma with AL amyloidosis) 
Case 32-2012 (DAH with Nephritis) 
Case 11-2012 (RMSF / Maculopapular Rash) 
Case 33-2010 (Aspergillus Endophthalmitis / Posterior Uveitis / DDx: Acute Renal Failure) 
Case 23-2010 (Secondary Polycythemia due to Renal lymphangiectasis / Renal Cysts / MGUS) 
Case 31-2005 (Type II cryoglobulinemia with renal disease)