Acute renal failure

Etiology

Prerenal azotemia

• Dehydration
• Hemorrhage, e.g., GI bleeding
• Congestive heart failure
• Renal artery stenosis including fibromuscular dysplasia
• NSAIDs, ACE inhibitors

• Obstruction, e.g., BPH, bladder tumor, pelvic mass

• Toxins: NSAIDs, antibiotics, contrast, multiple myeloma, rhabdomyolysis, hemolysis, chemotherapy, hyperuricemia, cyclosporine
• Ischemia, e.g., prolonged prerenal azotemia

• Immune complex: IgA nephropathy, endocarditis, SLE, cryoglobulinemia, postinfectious, membranoproliferative, Henoch-Schönlein purpura
• Pauci-immune (ANCA+): Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyarteritis
• Anti-GBM: Goodpasture's syndrome, anti-GBM glomerulonephritis
• Other: malignant hypertension, TTP, scleroderma renal crisis, preeclampsia-eclampsia

• Drugs: beta-lactams, sulfa, diuretics, NSAIDs, rifampin, phenytoin, allopurinol
• Infections: Streptococcus, leptospirosis, CMV, histoplasmosis, Rocky Mountain spotted fever
• Immune: SLE, Sjögren's syndrome, sarcoidosis, cryoglobulinemia