Rapid Evaluation of Acute Kidney Injury With NGAL in Acutely Ill Patients in the ICU

Inclusion Criteria: * Subjects must be 21 years of age or older. * Subjects must be admitted to an Intensive Care Unit (medical or surgical) and must be enrolled into this study within 12 hours of receipt of ICU admission orders. * Subjects must be assessed as likely to be alive in the ICU for a minimum of 48 hours after enrollment. * The following plasma/serum creatinine values must be available: * Subjects that are admitted to the ICU following an elective surgery or procedure must have at least one pre-surgical/ pre-procedure creatinine value obtained in the 7 days prior to presentation to the ICU. * Subjects that are admitted to the ICU for any reason other than following an elective surgery or procedure must have at least one creatinine value obtained greater than 7 days and up to 6 months prior to presentation to the ICU. Exclusion Criteria * Subjects either receiving or in imminent need of Renal Replacement Therapy. * Subjects with evidence of chronic kidney disease stages 4 and 5 as evidenced by a pre-enrollment estimated GFR of less than 30 mL/min/1.73M2 (according to the 4-variable MDRD22). * Subjects with any obstructive uropathy at the time of presentation to the ICU. * Subjects with any known urothelial, urological or kidney malignancies. * Subjects that have had any urologic procedure or surgery immediately prior to admission to the ICU. * Subjects that have had any renal transplant or nephrectomy. * Subjects that have had cardiovascular surgery involving cardiopulmonary bypass within the previous 7 days. * Subjects that have participated in an interventional clinical study within the previous 30 days including studies with any investigational and non-investigational drugs. * The inability to obtain written Informed Consent from the subject or an authorized representative. * Subjects that have been previously enrolled in this study during a prior admission to the ICU.