Persistent But Not Transient Acute Kidney Injury Was Associated With Lower Transplant-Free Survival in Patients With Acute Liver Failure: A Multicenter Cohort Study

OBJECTIVES: Acute liver failure (ALF) is an orphan disease often complicated by acute kidney injury (AKI). We assessed the impact of transient versus persistent AKI on survival in patients with ALF. DESIGN: International multicenter retrospective cohort. SETTING: U.S. ALF Study Group prospective registry. PATIENTS: Patients with greater than or equal to 18 years and ALF in the registry from 1998 to 2016 were included. Patients with less than 3 days of follow-up, without kidney function evaluation on day 3, or with cirrhosis were excluded. INTERVENTIONS: AKI was defined by Kidney Disease Improving Global Outcomes guidelines on day 1. Kidney recovery was defined on day 3 as transient AKI, by a return to no-AKI within 48 hours or persistent AKI if no such recovery or renal replacement therapy (RRT) was observed. Primary outcome was transplant-free survival (TFS) at 21 days. MEASUREMENTS AND MAIN RESULTS: Among 1,071 patients with ALF, 339 (31.7%) were males, and median (interquartile range) age was 39 years (29-51 yr). Acetaminophen-related ALF was found in 497 patients (46.4%). On day 1, 485 of 1,071 patients (45.3%) had grade 3-4 hepatic encephalopathy (HE), 500 of 1,070 (46.7%) required invasive mechanical ventilation (IMV), 197 of 1,070 (18.4%) were on vasopressors, and 221 of 1,071 (20.6%) received RRT. On day 1, 673 of 1,071 patients (62.8%) had AKI. On day 3, 72 of 1,071 patients (6.7%) had transient AKI, 601 of 1,071 (56.1%) had persistent AKI, 71 of 1,071 (6.6%) had late onset AKI, and 327 of 1,071 (30.5%) remained without AKI. Following adjustment for confounders (age, sex, race, etiology, HE grade, use of IMV and vasopressors, international normalized ratio, and year), although persistent acute kidney injury (adjusted odds ratio [aOR] [95% CI] 0.62 [0.44-0.88]) or late onset AKI (aOR [95% CI] 0.48 [0.26-0.89]) was associated with lower TFS, transient AKI was not (aOR [95% CI] 1.89 [0.99-3.64]). CONCLUSIONS: In a multicenter cohort of patients with ALF, persistent but not transient AKI was independently associated with lower short-term TFS.