This study is to evaluate the NGAL point of care device as an aid in the early risk assessment of AKI (acute kidney injury)in an All-Comers ED population.

This is a multi-center prospective pilot clinical study to assess the utility of the Triage neutrophil gelatinase-associated lipocalin (NGAL) Test as an aid in the early risk assessment for development of acute kidney injury (AKI) (sub clinical minimal changes in creatinine levels to complete failure resulting in kidney replacement therapy) in an all-comers population of patients presenting to the Emergency Department (ED) and designated for hospital admission.. The secondary objectives are to assess the utility of the Triage NGAL Test as an aid in the assessment of AKI severity in patients presenting to the ED, to determine if the combination of Triage NGAL measurements and clinical judgment can improve the early risk assessment for the development of AKI and to correlate Triage NGAL levels to patient outcomes.

Approximately 700 adults presenting to the ED and designated for admission to the hospital will be enrolled. The treating physician will note their preliminary ED diagnosis of AKI vs. no AKI (including prerenal azotemia, non-progressive chronic kidney disease (CKD) and preserved renal function) and their level of confidence in that diagnosis as a percentage following the initial exam.

EDTA anti-coagulated blood samples (for Triage NGAL Test) and blood samples for processing to serum (for Cystatin C test) will be collected and measured for NGAL and Cystatin C levels in all subjects at the following time points:

• immediately upon decision to admit to the hospital from the ED [baseline],
• at 6 and 12 hours after baseline draw
• on days 1, 2 and 3 following admission to the hospital, and
• on the day of hospital discharge (if the subject is hospitalized beyond day 3)

The results of these NGAL and Cystatin C assessments will be blinded to the medical team during the study and will not impact the medical management of the subject.

Blood samples for unblinded standard of care assessment of serum creatinine (analyzed at the hospital's laboratory) will also be obtained:

• in the ED [baseline],
• on days 1, 2 and 3 following admission to the hospital, and
• on the day of hospital discharge (if the subject is hospitalized beyond day 3)

Additional study specific blood samples for blinded assessment of serum creatinine (analyzed at the hospital's laboratory) will also be obtained:

• at 6 and 12 hours after baseline draw

Inclusion Criteria:

1. Males and females 18 years of age or older;
2. Patients presenting to the ED who have been designated for hospital admission
3. Ability to provide blood samples for baseline NGAL, Cystatin C and creatinine levels either prior to or at admission;
4. Ability to provide written informed consent.

Exclusion Criteria:

1. Known history of marked chronic renal insufficiency (e.g., usual serum creatinine ³ 3.0 mg/dL), on dialysis or RRT (either acute or chronic) or in imminent need of dialysis or RRT at enrollment;
2. Patients with urothelial malignancies;
3. Patients not expected to be admitted and therefore unable to fulfil protocol requirements for blood collection out to day 3 post admission time points
4. Prisoners or other institutionalized or vulnerable individuals;
5. Participation in an interventional clinical study within the previous 30 days;
6. Unlikely to be willing or able to comply with study procedures.

Adults presenting to the ED and designated for admission to the hospital will be enrolled.