A 25-year-old man comes to the physician for evaluation of abnormal liver tests. Blood work performed for graduate school enrollment revealed elevated bilirubin levels. He has no complaints and feels well. He reports that he had a history of jaundice and hepatitis at the age of 5. He took azithromycin for an upper respiratory infection approximately 2 months ago. He has no other medical problems. He does not smoke or drink alcohol, and he denies any recreational drug use.
Physical examination is unremarkable.
Laboratory results are as follows:

Which of the following is the best next step in management for this patient?

Question

A 25-year-old man comes to the physician for evaluation of abnormal liver tests.  Blood work performed for graduate school enrollment revealed elevated bilirubin levels.  He has no complaints and feels well.  He reports that he had a history of jaundice and hepatitis at the age of 5.  He took azithromycin for an upper respiratory infection approximately 2 months ago.  He has no other medical problems.  He does not smoke or drink alcohol, and he denies any recreational drug use.
Physical examination is unremarkable.
Laboratory results are as follows:

Which of the following is the best next step in management for this patient?

Quizplus · Accepted Answer

11ec193a_97f9_a37e_853d_a5aa8a621251_MD0002_00 This patient's isolated unconjugated hyperbilirubinemia is most likely due to Gilbert's syndrome. Gilbert's syndrome results in decreased production (< 30% of normal) of UDP-glucuronyl transferases, deficiency of which leads to decreased glucuronidation of bilirubin and unconjugated hyperbilirubinemia. Patients typically are asymptomatic or may present with nonspecific symptoms (e.g., fatigue) and icterus on examination. The bilirubin levels are usually < 3-4 g/dL, but they can significantly increase with fasting for 24 to 48 hours, hemolysis, febrile illness, or medication use (e.g., nicotinic acid). Diagnosis is suggested by unconjugated hyperbilirubinemia with otherwise normal laboratory results (e.g., CBC, liver function tests, and hemolysis tests) and confirmed with repeat testing in 6-12 months that shows continued isolated unconjugated hyperbilirubinemia. Genetic testing for the UGT1A1 gene mutation is usually reserved for patients with an unclear diagnosis (Choice D). Gilbert's syndrome requires no further testing or specific therapy. This patient's normal liver enzymes and hepatic function rule out pre- and post-hepatic causes. The normal reticulocyte count and LDH do not suggest hemolysis. Given his immunity to hepatitis A (positive IgG HAV antibodies), Gilbert's syndrome is the most likely diagnosis by exclusion. (Choice A) Antinuclear antibodies can evaluate for SLE or autoimmune hepatitis, but this patient's normal liver function tests (except for bilirubin) and lack of symptoms make these unlikely. (Choice B) CT scan of the abdomen can help evaluate cholestatic disease or possible hepatic parenchymal lesions. However, this patient's otherwise normal liver function tests (except for bilirubin) make these scenarios unlikely. (Choice C) Phenobarbital is a hepatic enzyme inducer that can increase glucuronidase activity and decrease bilirubin levels. However, patients do not routinely need hepatic inducers (e.g., phenobarbital) since Gilbert's syndrome is a benign disease. Educational objective: Gilbert's syndrome usually presents with asymptomatic isolated unconjugated hyperbilirubinemia with normal liver enzymes and negative work-up for hemolysis. Further invasive tests or treatments are not necessary due to the benign nature of the disease. __________ References: The genetic basis of the reduced expression of bilirubin UDP-glucuronosyltransferase 1 in Gilbert's syndrome (http://www.ncbi.nlm.nih.gov/pubmed/7565971) Eponym : Gilbert syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/22160004)

A 25-Year-Old Man Comes to the Physician for Evaluation of Abnormal