Complement Activation Fragments Are Increased in Critically Ill Pediatric Patients with Severe AKI. Issue 12 (30th December 2021)

• Record Type: Journal Article
• Authors: Stenson, Erin K.; You, Zhiying; Reeder, Ron; Norris, Jesse; Scott, Halden F.; Dixon, Bradley P.; Thurman, Joshua M.; Frazer-Abel, Ashley; Mourani, Peter; Kendrick, Jessica
• Is Part Of: Kidney360. Volume 2:Issue 12(2021)
• Page Start: 1884
• Page End: 1891
• Publication Date: 2021-12-30
• Subjects: acute kidney injury and ICU nephrology -- acute kidney injury -- complement -- complement activation -- critical illness -- pediatric nephrology; 616.61
• DOI: 10.34067/KID.0004542021
• Languages: English
• ISSNs: 2641-7650

Abstract

Visual Abstract: Abstract : Key Points: Multiple urine and plasma complement fragments increase as severity of AKI increases in children who are critically ill. Complement fragments may identify patients at risk of requiring dialysis or developing major adverse kidney event outcomes. Future studies evaluating this association in a larger cohort of children, and studying complement inhibition, are warranted. Background: Children who are critically ill with AKI suffer from high morbidity and mortality rates, and lack treatment options. Emerging evidence implicates the role of complement activation in AKI pathogenesis, which could potentially be treated with complement inhibitors. The purpose of this study is to evaluate the association between complement activation fragments and severity of AKI in children who are critically ill. Methods: A biorepository of samples from children who are critically ill from a prior multisite study was leveraged to identify children with stage 3 AKI and matched to patients without AKI on the basis of PELOD-2 (illness severity) scores. Specimens were analyzed for plasma and urine complement activation fragments of factor B, C3a, C4a, and sC5b-9. The primary outcomes were MAKE30 and severe AKI rates. Results: In total, 14 patients with stage 3 AKI (five requiring RRT) were matched to 14 patients without AKI. Urine factor Ba and plasma C4a levels increased stepwise as severity of AKI increased, from no AKI to stage 3 AKI, to stage 3 AKI with RRT need. Plasma C4a levels were independently associated with increased risk of MAKE30 outcomes (OR, 3.2; IQR, 1.1–8.9), and urine Ba (OR, 1.9; IQR, 1.1–3.1), plasma Bb (OR, 2.7; IQR, 1.1–6.8), C4a (OR, 13.0; IQR, 1.6–106.6), and C3a (OR, 3.3; IQR, 1.3–8.4) were independently associated with risk of severe stage 2–3 AKI on day 3 of admission. Conclusions: Multiple complement fragments increase as magnitude of AKI severity increases. Very high levels of urine Ba or plasma C4a may identify patients at risk for severe AKI, hemodialysis, and MAKE30 outcomes. The fragments may be useful as a functional biomarker of complement activation and may identify those patients to study complement inhibition to treat or prevent AKI in children who are critically ill. These findings suggest the need for further specific investigations of the role of complement activation in children who are critically ill and at risk of AKI.