AbstractsMedical & Health Science

Acute kidney injury (AKI) is a common complication in patients with cirrhosis and is associated with significant mortality. Despite the overall poor outcomes, there exists hope for such patients as, unlike in the majority of setting of AKI, specific treatments are available which have been shown to improve renal function and mortality. However, historically intransient difficulties in differential diagnosis and prognosis have limited the extent to which such treatments can be appropriately utilized. In addition, though AKI has long been appreciated as a feared complication, the definitions of AKI employed in studies involving patients with cirrhosis have not been standardized, lack sensitivity, and have often been limited to narrow clinical settings. We conducted a multicenter, prospective observational cohort study of patients with cirrhosis and AKI, drawn from multiple hospital wards, utilizing the modern acute kidney injury network (AKIN) definition and assessed the association between AKI severity and progression with in-hospital mortality. Following this we investigated whether early changes in serum cystatin C levels were more closely associated with subsequent outcomes than similarly early changes in serum creatinine. We subsequently assessed whether novel biomarkers of kidney structural injury, measured on the day of fulfilling AKI criteria, can predict progression of AKI and mortality. Finally, we investigated the ability of biomarkers to assist with differential diagnosis and potentially change the way in which causes of AKI in cirrhosis are conceptualized. 192 patients were enrolled and included in the study. In the first phase, 85 (44%) of these were found to progress to a higher AKIN stage after initially fulfilling AKI criteria. Patients achieved a peak severity of AKIN stage 1, 26%, stage 2, 24%, and stage 3, 49%. Progression was significantly more common and peak AKI stage higher in non-survivors than survivors (p < 0.0001). After adjusting for baseline renal function, demographics and critical hospital and cirrhosis-associated variables, progression of AKI was independently associated with mortality (adjusted odds ratio = 3.8, 95% confidence interval (CI) 1.3-11.1). We conclude that AKI, as defined by AKIN criteria, in patients with cirrhosis is frequently progressive and severe and is independently associated with mortality in a stage-dependent fashion. Unfortunately, accurately predicting which patients will experience the worst outcomes is challenging as serum creatinine correlates poorly with glomerular filtration in patients with cirrhosis and fluctuations may mask progression early in the course of AKI. Cystatin C, a low-molecular-weight cysteine proteinase inhibitor, is a potentially more accurate marker of glomerular filtration. In the second phase of our study we evaluated whether early changes in serum cystatin C would associate more strongly with a composite endpoint of dialysis or mortality than early changes in creatinine. Of 106 patients studied with at least 2…