“…Since acute tubular necrosis preferentially affects S3, the disruption of this mechanism could be relevant in explaining (partially) the decreased excretion of urea observed in ischemic AKI. 27,28 In clinical practice, FeNa is routinely used to discriminate between functional changes (prerenal) and kidney damage (renal AKI). By disturbing tubular Na reabsorption, diuretics decrease the sensitivity/specificity of FeNa.…”