system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 19-year-old man comes to the physician because of recurrent yellowing of his eyes over the past 2 years. He reports that each episode lasts 1–2 weeks and resolves spontaneously. He has no family history of serious illness. He recently spent a week in Mexico for a vacation. He is sexually active with two partners and uses condoms inconsistently. He does not drink alcohol or use illicit drugs. His vital signs are within normal limits. Physical examination shows jaundice of the conjunctivae and the skin. The abdomen is soft with no organomegaly. The remainder of the physical examination shows no abnormalities. Laboratory studies show:
Serum
Total bilirubin 4.0 mg/dL
Direct bilirubin 3.0 mg/dL
Alkaline phosphatase 75 U/L
AST 12 U/L
ALT 12 U/L
Anti-HAV IgG positive
HBsAg negative
Anti-HBsAg positive
HCV RNA negative
Urine
Bilirubin present
Urobilinogen normal
Which of the following is the most likely underlying cause of this patient's condition?"
assistant
Impaired hepatic storage of bilirubin