1. Immunomodulation of Regional Citrate Anticoagulation in Acute Kidney Injury Requiring Renal Replacement Therapy Sasipha Tachaboon 1, Khajohn Tiranatanakul 2 and Nattachai Srisawat 3 1Master of Science Program in Medical Sciences, Faculty of Medicine, Chulalongkorn University, 2Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, and 3Excellence Center for Critical Care Nephrology, King Chulalongkorn Memorial Hospital, Thai Red Cross.

2. Background Acute Kidney Injury [AKI] is a common health problem in ICU. AKI can also lead to decreased survival and increased risk of mortality in critically ill patients. Continuous Renal Replacement Therapy [CRRT] is considered as a standard treatment for AKI patients. Regional citrate anticoagulation [RCA] is an alternative anti-coagulation for CRRT. It is associated with inflammatory cell functions improving patient survival. RCA potentially affects the immunomodulation.

3. We aim to study the effect of regional citrate anticoagulation in immune response in patients with AKI undergoing CRRT. Objective

4. This prospective randomized controlled trial was performed of 30 AKI patients requiring CRRT at King Chulalongkorn Memorial hospital. The participants were randomized to either RCA group [n = 15] or control group [n = 15]. Blood samples were collected to measure CD 11b, HLA-DR, C3a, C5a and PAI-1 at baseline, six hours and 24 hours after start of CRRT. Method

5. A total of AKI patients with CRRT were recruited and randomized into control and regional citrate anticoagulation group. The demographic data and baseline are not different in each groups. Regional citrate anticoagulation group significantly results in high percentage of the reduction in CD11b at 24 hours (-41.5 vs. 7.1 %, p = 0.02), concordantly with HLA-DR at 24 hours (-5.17 vs. 35.63 %, p = 0.02) and PAI-1 at 24 hours (-18.92 vs. 21.41, p = 0.03). Moreover, biomarkers including c3a and c5a decreased over time during CRRT. Results

6. Functions of cell surface markers among two groups.

7. ggf Results 28-days survival in AKI patients with CRRT among two groups.

8. RCA in CRRT reduced inflammatory effects of the immune system and mortality rate in AKI patients. RCA provides potential benefits for CRRT in AKI. Conclusion

9. Acknowledgement Master of Science Program in Medical Sciences, Faculty of Medicine, Chulalongkorn University. Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University. Excellence Center for Critical Care Nephrology, King Chulalongkorn Memorial Hospital, Thai Red Cross. Graduate grant from National Research Council of Thailand (NRCT) 2558.