Oliguria: an earlier and accurate biomarker of acute kidney injury?

In the context of the critically ill patient, the onset of consistent oliguria is an ominous sign that requires immediate attention. Without intervention, intermittent oliguria may turn into persistent oliguria or evolve to acute kidney injury (AKI), with severe associated morbidity and mortality. Whether the addition of urine output to the serum creatinine criteria permits earlier and more specific detection of AKI is controversial, but current evidence supports its importance in early diagnosis and management.