LAUSR

CASE A previously well 16-year-old female presented to an emergency department with a 3-day history of jaundice, dark urine and right-sided abdominal pain. Her illness began a week prior with intermittent fever, decreased appetite and fatigue. Over the preceding 3 days, she noted a progressive worsening of her jaundice but denied nausea, vomiting, pruritus or pale stools. She lived in Miami and had never traveled outside of the United States. The patient had no history of recent trauma, alcohol consumption, blood transfusions or tobacco use, and she denied medication or illicit drug use. On examination, the patient was well appearing, with a temperature of 38.7°C, pulse rate of 100 beats/min, respiratory rate of 20 breaths/min and blood pressure of 107/63 mm Hg. She appeared jaundiced with bilateral scleral icterus. Her abdomen was remarkable for epigastric tenderness as well as hepatomegaly and splenomegaly, measured at 2 and 1 cm below the costal margin, respectively. The tonsils and pharynx appeared normal with no lymphadenopathy or skin rash appreciated. Initial laboratory investigations were significant for white blood cell count of 23.3 × 10/L (4–10.5 × 10/L) with 6% neutrophils, 77% lymphocytes, 1% monocytes and 15% atypical lymphocytes, hemoglobin of 11.9 g/dL (11.1–14.6 g/dL), platelet count of 228 × 10/L (140–400 × 10/L), alanine aminotransferase of 448 U/L (9–52 U/L), aspartate aminotransferase of 546 U/L (15– 46 U/L), alkaline phosphatase of 449 U/L (38–126 U/L), gamma-glutamyl transferase of 224 U/L (3–20 U/L) and total bilirubin of 8.2 mg/dL (0.2–1.3 mg/dL). Ultrasound examination of the abdomen demonstrated gallbladder wall thickening (measuring 9.1 mm) without gallbladder distension, intramural gas, biliary sludge, sonographic Murphy sign or intraluminal cholelithiasis. Computed tomography imaging also revealed splenomegaly (see Fig. 1), but no evidence of pericholecystic fluid, gallstones, bile duct dilatation or other hepatobiliary anomalies. After initial stabilization, the patient was transferred to our center for evaluation of symptomatic cholestatic hepatitis. Serologic and virologic studies for hepatitis viruses A, B, C, cytomegalovirus, heterophile antibody, antinuclear antibody, antismooth muscle antibody and antiliver kidney microsomal antibodies were all negative. Immunoglobulin levels were within normal limits, and a blood acetaminophen level and urinary toxicology screen for common drugs of abuse were all unremarkable. On the second day of hospitalization, the patient remained jaundiced with intermittent febrile episodes, decreased appetite and fatigue. A coagulation panel was within normal limits but total and direct bilirubin continued to be elevated at 7.5 mg/dL (0.2– 1.3 mg/dL) and 5.9 mg/dL (0–0.4 mg/dL), respectively. An additional test confirmed the diagnosis. For Denouement see P. 878. Your Diagnosis, Please