Sustained hyperbilirubinemia following clarithromycin administration

Abstract

Abstract Rationale: Hyperbilirubinemia is observed in drug-induced liver injury of cholestatic type, but direct inhibition of transporter proteins which facilitates bilirubin transport also causes hyperbilirubinemia. Here we present a case of sustained hyperbilirubinemia after the administration of clarithromycin. Patient concerns: A 52-year-old man was referred to our hospital because of sustained hyperbilirubinemia. Both contrast-enhanced computed tomography and Magnetic resonance cholangiopancreatography did not reveal any abnormality. But his liver was not enhanced in the hepatocellular phase of Gd-EOB-DTPA MRI. Indocyanine Green (ICG) retention rate at 15 minutes (ICG(R15)) was 58%, urinary coproporphyrin was 324 μg/g Cr, and serum bile acid was 283 nmol/mL. Technetium-99m galactosyl human serum albumin (99mTc-GSA) liver scintigram revealed that his liver function was normal (blood clearance ratio (HH15), 0.572; and hepatic uptake ratio (LHL15), 0.948) Diagnoses: These findings suggested that hyperbilirubinemia in the present case was caused by impaired organic anion-transporting polypeptide (OATP) 1B1 and 1B3 activity. Drug-induced lymphocyte stimulation test (DLST) for clarithromycin was positive. Among the drugs prescribed before the presentation of hyperbilirubinemia, clarithromycin is the only agent that has been reported to reduce the OATP1B1/1B3 transporter activity. Interventions: The patient continued taking oral UDCA, but hyperbilirubinemia did not improve. Bilirubin absorption therapy was performed twice. Outcomes: Following bilirubin absorption therapy, hyperbilirubinemia resolved and the bilirubin levels became normal. With the decrease in serum bilirubin, the liver was normally enhanced on the hepatocellular phase of Gd-EOB-DTPA MRI. ICG(R15). Urinary coproporphyrin, and bile acid levels returned to normal range (ICG(R15) of 9.2%, urinary coproporphyrin of 58 μg/g Cr, and bile acid of 13.5 nmol/mL). Lessons: The present case indicates that uptake of Gd-EOB-DTPA in the liver, ICG retention test, serum bile acid levels combined with urinary coproporphyrin can be a potential marker of OATP transporter activity and help in differential diagnosis of sustained hyperbilirubinemia.