KDIGO Clinical Practice Guideline for Acute Kidney Injury
Limitations to current definitions for AKI

Limitations to current definitions for AKI

Unfortunately, the existing criteria-while extremely useful and widely validated-are still limited. First, despite efforts to standardize the definition and classification of AKI, there is still inconsistency in application.^26,27 A minority of studies have included urinary output criteria despite its apparent ability to identify additional cases^6,29 and many studies have excluded patients whose initial SCr is already elevated. Preliminary data from a 20 000-patient database from the University of Pittsburgh suggests that roughly a third of AKI cases are community-acquired³³ and many cases may be missed by limiting analysis to documented increases in SCr. Indeed, the majority of cases of AKI in the developing world are likely to be community-acquired. Thus, few studies can provide accurate incidence data. An additional problem relates to the limitations of SCr and urine output for detecting AKI. In the future, biomarkers of renal cell injury may identify additional patients with AKI and may identify the majority of patients at an earlier stage.