U_Na=20, S_Cr=1,5, S_Na=140, U_Cr=120 → FENa = 0,1786% (преренальное) FENa = (20×1,5)/(140×120)×100 = 0,1786%. Менее 1% — соответствует преренальной азотемии.{"result":"FENa = 0.1786% (< 1% — Consistent with prerenal azotemia). Method: FENa = (U_Na·S_Cr)/(S_Na·U_Cr)·100.","metadata":{"input":{"urineSodium":20,"serumCreatinine":1.5,"serumSodium":140,"urineCreatinine":120},"result":{"fena":0.1786,"unit":"%","category":"< 1%","interpretation":"Consistent with prerenal azotemia (sodium-avid state). Consider volume depletion, heart failure, hepatorenal syndrome. Caution: contrast/sepsis ATN and diuretics can also yield low FENa.","method":"FENa = (U_Na·S_Cr)/(S_Na·U_Cr)·100","model":"Espinel CH. JAMA 1976;236(6):579-581. Most useful in oliguric AKI. Not medical advice."}}}
U_Na=60, S_Cr=2,0, S_Na=135, U_Cr=60 → FENa = 1,4815% (внутрипочечное/ОКН) FENa = (60×2,0)/(135×60)×100 = 1,4815%. ≥1%, соответствует внутрипочечному повреждению (обычно ОКН).{"result":"FENa = 1.4815% (1–4% — Consistent with intrinsic renal injury, typically ATN). Method: FENa = (U_Na·S_Cr)/(S_Na·U_Cr)·100.","metadata":{"input":{"urineSodium":60,"serumCreatinine":2,"serumSodium":135,"urineCreatinine":60},"result":{"fena":1.4815,"unit":"%","category":"1–4%","interpretation":"Consistent with intrinsic renal injury, typically acute tubular necrosis (ATN). Damaged tubules cannot reabsorb sodium effectively.","method":"FENa = (U_Na·S_Cr)/(S_Na·U_Cr)·100","model":"Espinel CH. JAMA 1976;236(6):579-581. Most useful in oliguric AKI. Not medical advice."}}}