['The definition of "early" in terms of continuous renal replacement therapy (CRRT) initiation has not been uniformly used. Therefore, we tried to elucidate whether the timing of CRRT application, based on the interval between the start time of vasopressors infusion and CRRT initiation, was an independent predictor of mortality in the patients with septic acute kidney injury (AKI).', 'Progressive septic AKI patients, in whom the infusion doses of vasopressors were increased compared with the initial dose during the first 6 hours of vasopressor treatment and CRRT was performed, between 2009 and 2011, were collected and divided into 2 groups based on the median interval between the 2 points.', 'A total of 210 patients were included. The mean age was 62.4 years, and 126 patients (60.0%) were male. The most common comorbid disease was malignancy (53.8%), followed by hypertension (35.7%) and diabetes mellitus (29.0%). The median interval between the start time of vasopressor infusion and CRRT commencement was 2.0 days. During the study period, 156 patients (74.3%) died within 28 days of CRRT application. The interval between 2 points was significantly shorter in the survivor compared with the death group (P < .001). Moreover, 28-day overall mortality rates in the early CRRT group were significantly lower than those in the late CRRT group (P = .034). Furthermore, early CRRT treatment was independently associated with a lower mortality rate even after adjustment for age, sex, causative organisms, and infection sites (P = .032).'] Does early initiation of continuous renal replacement therapy improve patient survival in severe progressive septic acute kidney injury?