A Rare Diagnosis of Dubin‐Johnson Syndrome During Pregnancy: A Case Report

ABSTRACT

Dubin‐Johnson Syndrome (DJS) is a rare inherited disorder characterized by isolated conjugated hyperbilirubinemia without significant liver damage. This syndrome is often diagnosed incidentally during routine blood tests, as it typically presents with minimal or no symptoms. The disease results from a genetic defect in the ABCC2 gene, which encodes the MRP2 protein responsible for transporting conjugated bilirubin out of hepatocytes. In individuals with DJS, the impaired function of MRP2 leads to the accumulation of conjugated bilirubin in the liver and bloodstream. This case report presents a 31‐year‐old female who, during pregnancy, developed icterus, which raised concerns about possible liver disease or viral hepatitis. However, further investigation revealed no significant liver dysfunction or risk factors for viral hepatitis. Laboratory tests showed elevated total and direct bilirubin levels, with normal liver enzymes, thus prompting further evaluation. Ultrasound imaging of the liver and biliary system revealed no signs of obstruction, and tests for viral hepatitis were negative. The patient's clinical history of icterus since childhood, combined with the laboratory findings, led to the suspicion of DJS. Notably, urine coproporphyrin analysis demonstrated a characteristic increase in coproporphyrin I, further supporting the diagnosis. Although DJS does not typically require treatment, the patient was provided with genetic counseling to inform her and her family about the condition and potential inheritance patterns. DJS presents a diagnostic challenge due to its subtle clinical features and the need to differentiate it from other causes of icterus, especially in pregnancy. This case highlights the importance of considering rare genetic disorders in the differential diagnosis of icterus and emphasizes the role of genetic testing in confirming the diagnosis. Early recognition of DJS allows for appropriate management and genetic counseling, ensuring that affected individuals can lead a normal life without major complications.