Pediatric Acute Liver Failure and Immune Dysregulation

Abstract

Apreviously healthy 2-year-old girl was taken to a communityhospitalwith anacuteonsetof jaundice overa several-day period. Her initial exam was remarkable for mild hepatomegaly. There was no splenomegaly or history of fever. Screening laboratory tests revealed elevated aminotransferase levels, conjugated hyperbilirubinemia, and thrombocytopenia. Her international normalized ratio was normal. An evaluation for causes of acute hepatitis revealed negative viral studies and a nondetectable serum acetaminophen level; negative serum antinuclear antibody, anti–smooth muscle antibody, and anti–liver/kidney microsomal antibody; and normal serum immunoglobulin level. Because of thrombocytopenia in the setting of hepatitis, she was evaluated for hemophagocytic lymphohistiocytosis (HLH). This evaluation demonstrated normal fasting serum triglyceride levels, an elevated serum ferritin level of 616 ng/ mL, and a low-normal serum fibrinogen level of 167 mg/dL. Serum soluble interleukin (IL)-2 receptor (sIL-2R) level was markedly elevated at 9998 U/mL. Bone marrow biopsy showed no evidence of hemophagocytosis. Liver biopsy showed lobular and sinusoidal lymphocytic inflammation but no hemophagocytosis. Although the patient had an elevated serum ferritin, and an elevated sIL-2R level, she did not fulfill the criteria for HLH according to recent