2.1. Study Design and Setting

We studied prospectively 121 adult patients diagnosed as SA-AKI admitted to the ICU, Trung Vuong Hospital, Ho Chi Minh, Viet Nam. We excluded patients below 16 years of age, patients with non-SA-AKI, patients with chronic kidney disease, organ transplant recipients, patients with malignancy, pregnant women, patients admitted for observation to stay in the ICU for <48 h, and died patients with all-cause. To determine the predictive value of both urine and serum NGAL, all patients with anuria were excluded from the study. A written informed consent and Hospital's Ethics Committee clearance were obtained before the recruitment of the participants for the study.

Preexisting comorbidities such as diabetes mellitus and hypertension and medications were noted. Diabetes mellitus was identified according to either a physician's diagnosis, antidiabetic drug treatment, or 2 subsequent analyses demonstrating fasting blood glucose levels of >126 mg/dl or >7.0 mmol/l. Hypertension was defined as the regular use of antihypertensive drugs for controlling blood pressure or at least 2 blood pressure measurements of >140/90 mm Hg. Demographic data such as age, gender, comorbid conditions, clinical setting such as medical or surgical, and presence of sepsis were noted. In our study, we used the Sequential Organ Failure Assessment (SOFA) score to define single organ failure (SOF) and multiple organ failure (MOF) [22]. SOF was defined when the SOFA score was more than 3 in a particular organ at any time of hospitalization [23]. MOF was defined when two or more organ failure was confirmed (Table 1).

Definitions of single organ failure.

AKI: acute kidney injury; SOFA: Sequential Organ Failure Assessment.