MtDNA 3243 A>G mutation and recurrent cholangitis after Kasai procedure in biliary atresia: a case report.

Background: Cholangitis following the Kasai procedure contributes to a poor prognosis in biliary atresia (BA). We report a case of a pediatric patient with BA who developed recurrent cholangitis after undergoing a Kasai procedure and was subsequently found to carry the mitochondrial DNA (mtDNA) 3243 A>G mutation. Case Description: This case involves a 7-month-old female infant who, at 2 months of age, exhibited symptoms including jaundice, stool discoloration, and dark urine, prompting a diagnosis of hyperbilirubinemia. Hepatobiliary dynamic imaging suggested BA, a diagnosis confirmed by abdominal ultrasound and laparoscopic exploration at our hospital. She underwent a Kasai procedure and was discharged on day 19. However, recurrent, treatment-resistant cholangitis subsequently led to her readmission. Given the patient's complex clinical course, genetic testing, conducted with informed consent, revealed a pathogenic mtDNA variant at position 3243 (A>G). Due to the severity of her condition, she underwent liver transplantation 5 months after the Kasai procedure. Conclusions: This article reports a rare case of the mtDNA 3243 A>G mutation presenting as recurrent cholangitis, suggesting that mitochondrial dysfunction may consistently induce inflammation. This case highlights the importance of recognizing mitochondrial mutations in BA due to their critical impact on the patient's prognosis. A comprehensive genetic evaluation may benefit patients with BA accompanied by recurrent cholangitis.