A 21-year-old male university student is brought to the emergency department by his roomma… — USMLE Step 2 CK

A 21-year-old male university student is brought to the emergency department by his roommate due to a 3-day history of progressively worsening confusion, severe fatigue, and yellowing of his skin. The roommate reports that over the past 3 months, the patient has exhibited unusual behavior, including severe paranoia and disorganized speech, which they attributed to the stress of upcoming exams. He takes no medications and does not consume alcohol or illicit drugs. His temperature is 37.0°C (98.6°F), blood pressure is 105/65 mmHg, and heart rate is 112/min. Physical examination reveals profound scleral icterus and generalized jaundice. The abdomen is distended with shifting dullness, and a firm, enlarged spleen is palpable. A coarse, "flapping" tremor is noted when the patient extends his arms and wrists.

Laboratory studies show:

Laboratory Test	Result	Reference Range
Hemoglobin	7.8 g/dL	13.5-17.5 g/dL
Reticulocyte count	9.2%	0.5-1.5%
Platelet count	88,000/mm³	150,000-400,000/mm³
Leukocyte count	6,500/mm³	4,500-11,000/mm³
Total bilirubin	22.4 mg/dL	0.1-1.2 mg/dL
Direct bilirubin	13.1 mg/dL	0.0-0.3 mg/dL
Aspartate aminotransferase (AST)	415 U/L	8-20 U/L
Alanine aminotransferase (ALT)	165 U/L	10-40 U/L
Alkaline phosphatase	16 U/L	40-120 U/L
Prothrombin time (PT)	26 sec	11-15 sec
INR	2.8	0.8-1.1

Direct antiglobulin (Coombs) test is negative. Which of the following is the most appropriate next step in management for this patient?

A
Initiation of empiric piperacillin-tazobactam
B
Administration of intravenous methylprednisolone
C
Initiation of oral valproic acid and psychiatric consultation
Immediate evaluation for orthotopic liver transplantationAnswer
E
Involuntary admission to the inpatient psychiatry unit

Answer

Immediate evaluation for orthotopic liver transplantation

This patient is presenting with acute liver failure (ALF), defined by the triad of severe acute liver injury (elevated aminotransferases), hepatic encephalopathy (confusion, asterixis), and synthetic dysfunction (INR ≥ 1.5) in a patient without known underlying cirrhosis. The specific etiology is fulminant Wilson disease. Key diagnostic clues include his young age, a prodrome of neuropsychiatric symptoms (paranoia), and Coombs-negative hemolytic anemia (low hemoglobin, elevated reticulocytes, predominantly indirect hyperbilirubinemia). Furthermore, the classic laboratory signature of Wilson disease ALF is an AST to ALT ratio greater than 2:1 and a characteristically low alkaline phosphatase (AP). An AP to total bilirubin ratio of less than 4 (here, 16 / 22.4 = 0.71) is highly sensitive and specific for this diagnosis. The rapid release of copper from necrotic hepatocytes causes both hemolysis and the displacement of zinc. Because zinc is a required cofactor for alkaline phosphatase synthesis, its displacement results in unusually low AP levels. In patients presenting with Wilson disease and ALF, medical therapy (e.g., copper chelation with D-penicillamine or trientine) is futile, takes too long to work, and is contraindicated. The condition is uniformly fatal without surgical intervention, making emergent evaluation for orthotopic liver transplantation the most appropriate next step.

Step-by-Step Solution

Identify the primary clinical syndrome.

The patient has jaundice, hepatic encephalopathy (confusion, asterixis), and severe coagulopathy (INR 2.8).

These three criteria define acute liver failure (ALF) in a patient without previously known underlying cirrhosis.

Determine the specific etiology of the acute liver failure using the clinical and laboratory data.

The combination of a psychiatric prodrome, Coombs-negative hemolytic anemia, AST:ALT ratio > 2, and notably low alkaline phosphatase (< 40 U/L) is virtually diagnostic of fulminant Wilson disease.

Massive copper release from necrotic hepatocytes causes intravascular hemolysis and displaces zinc (a necessary cofactor for alkaline phosphatase synthesis), leading to characteristically low alkaline phosphatase levels.

Select the appropriate definitive management based on the etiology.

Orthotopic liver transplantation is the only definitive and life-saving treatment.

Medical therapies (e.g., chelation with D-penicillamine or trientine) are ineffective and contraindicated in the setting of fulminant Wilson disease.

Key Concept

Wilson disease presenting as acute liver failure is uniquely characterized by Coombs-negative hemolytic anemia, an AST:ALT ratio > 2, and a markedly depressed alkaline phosphatase. The definitive treatment for this fulminant presentation is emergent liver transplantation.

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