title: Ammonia Level and Mortality in Acute Liver Failure: A Single-Center Experience.
abstract: BACKGROUND Acute liver failure (ALF) is an emergent condition that requires intensive care and manifests in particular by significant elevation in serum ammonia level. Patients with ALF with concomitant renal failure experience a further rise in ammonia levels due to decreased kidney excretion. The aim of this study was to evaluate the relationship between elevated ammonia levels and mortality and to characterize the subgroup of ALF patients who develop acute kidney injury (AKI) and require renal replacement therapy. MATERIAL AND METHODS This was a retrospective study of 36 consecutive patients admitted to Johns Hopkins Hospital's intensive care units from December 2008 to May 2013 who presented with grade III and IV hepatic encephalopathy (HE). Patients who developed AKI and required hemodialysis (HD) were compared to those without AKI. Patients with chronic kidney disease were excluded. RESULTS Sixteen patients developed AKI and underwent HD (HD group). Median ammonia levels in the HD and non-HD groups were not significantly different (p=0.95). In the HD group, 4 patients underwent liver transplantation (LT) and 3 of them survived the hospitalization. Among the 12 HD patients who did not receive LT, 6 (50%) survived. Out of 20 non-HD patients, 3 were transplanted, all of whom survived the hospitalization. Among the 17 non-HD patients who did not receive LT, 14 (82%) survived. Admission ammonia level (>120 µmol/L) was associated with higher mortality rate (OR=7.188 [95% CI 1.3326-38.952], p=0.026) in all patients. CONCLUSIONS Admission ammonia level is predictive of mortality in ALF patients with grade 3-4 HE.
authors.affiliation: Department of Gastroenterology, Osler Internal Medicine Residency Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Ashwini M
authors.initials: AM
authors.lastname: Niranjan-Azadi
authors.affiliation: Visiting Research Fellow, Transplant Hepatology, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Filiz
authors.initials: F
authors.lastname: Araz
authors.affiliation: Department of Gastroenterology, Osler Internal Medicine Residency Program, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Yuval A
authors.initials: YA
authors.lastname: Patel
authors.affiliation: Transplant Nephrology, Division of Nephrology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Nada
authors.initials: N
authors.lastname: Alachkar
authors.affiliation: Transplant Hepatology, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Saleh
authors.initials: S
authors.lastname: Alqahtani
authors.affiliation: Department of Transplant Surgery, Division of Liver Transplantation, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Cameron
authors.affiliation: Division of Neuroscience Critical Care, Departments of Anesthesiology and Critical Care Medicine and Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Robert D
authors.initials: RD
authors.lastname: Stevens
authors.affiliation: Transplant Hepatology, Division of Gastroenterology and Hepatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Gurakar
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000401:mortality / Q000628:therapy; D000328:Adult; D000641:Ammonia / Q000097:blood*; D005260:Female; D006501:Hepatic Encephalopathy / Q000097:blood; D006801:Humans; D017114:Liver Failure, Acute / Q000097:blood* / Q000401:mortality* / Q000628:therapy; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D006435:Renal Dialysis; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000641:Ammonia