Received November 5, 2006
Accepted on February 8, 2007

ORIGINAL ARTICLES

Septic Acute Kidney Injury in Critically Ill Patients: Clinical Characteristics and Outcomes

Sean M. Bagshaw ^*1, Shigehiko Uchino ^*¶¶, Rinaldo Bellomo ^*, Hiroshi Morimatsu , Stanislao Morgera , Miet Schetz ^||, Ian Tan ^¶, Catherine Bouman ^**, Ettiene Macedo , Noel Gibney , Ashita Tolwani , Heleen M. Oudemans-van Straaten , Claudio Ronco ^||||, John A. Kellum ^***, and for the Beginning and Ending Supportive Therapy for the Kidney (BEST Kidney) Investigators

*Department of Intensive Care and Department of Medicine, Austin & Repatriation Medical Centre, Melbourne, Australia; Division of Critical Care Medicine, University of Alberta, Edmonton, Alberta, Canada; Department of Anesthesiology and Resuscitology, Okayama University Medical School, Okayama, Japan; Department of Nephrology, University Hospital Charité, Berlin, Germany; ||Dienst Intensieve Geneeskunde, Universitair Ziekenhuis Gasthuisberg, Leuven, Belgium; ¶Intensive Care Unit, Department of Anaesthesia, Pamela Youde Nethersole Eastern Hospital, Hong Kong, China; **Adult Intensive Care Unit, Academic Medical Center, Amsterdam, The Netherlands; Nephrology Division, University of São Paulo School of Medicine, São Paulo, Brazil; Department of Medicine, Division of Nephrology, University of Alabama at Birmingham, Alabama, Alabama; Department of Intensive Care, Onze Lieve Vrouwe Gasthius, Amsterdam, The Netherlands; ||||Department of Nephrology, Intensive Care, St. Bortolo Hospital, Vicenza, Italy; ¶¶Intensive Care Unit, Department of Anesthesiology, Jikei University School of Medicine, Tokyo, Japan; and ***Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania

¹ To whom correspondence should be addressed. E-mail: bagshaw.sean{at}gmail.com.

	Abstract

Sepsis is the most common cause of acute kidney injury (AKI) in critical illness, but there is limited information on septic AKI. A prospective, observational study of critically ill patients with septic and nonseptic AKI was performed from September 2000 to December 2001 at 54 hospitals in 23 countries. A total of 1753 patients were enrolled. Sepsis was considered the cause in 833 (47.5%); the predominant sources of sepsis were chest and abdominal (54.3%). Septic AKI was associated with greater aberrations in hemodynamics and laboratory parameters, greater severity of illness, and higher need for mechanical ventilation and vasoactive therapy. There was no difference in enrollment kidney function or in the proportion who received renal replacement therapy (RRT; 72 versus 71%; P = 0.83). Oliguria was more common in septic AKI (67 versus 57%; P < 0.001). Septic AKI had a higher in-hospital case-fatality rate compared with nonseptic AKI (70.2 versus 51.8%; P < 0.001). After adjustment for covariates, septic AKI remained associated with higher odds for death (1.48; 95% confidence interval 1.17 to 1.89; P = 0.001). Median (IQR) duration of hospital stay for survivors (37 [19 to 59] versus 21 [12 to 42] d; P < 0.0001) was longer for septic AKI. There was a trend to lower serum creatinine (106 [73 to 158] versus 121 [88 to 184] µmol/L; P = 0.01) and RRT dependence (9 versus 14%; P = 0.052) at hospital discharge for septic AKI. Patients with septic AKI were sicker and had a higher burden of illness and greater abnormalities in acute physiology. Patients with septic AKI had an increased risk for death and longer duration of hospitalization yet showed trends toward greater renal recovery and independence from RRT.