Functional cure of a young child with chronic hepatitis B cirrhosis treated by pegylated interferon α combination therapy: A case report.

RATIONALE: Current research on antiviral treatment in children is relatively limited, especially in children under 1 year old.

PATIENT CONCERNS: Liu XX, an 8-month-old infant (case number: 3001120473), presented to the hospital in August 2016 with a chief complaint of being "hepatitis B surface antigen positive for 8 months and experiencing abnormal liver function for 5 months."

DIAGNOSES: The patient was diagnosed as chronic hepatitis B cirrhosis (G3S3-4) with active compensatory phase.

INTERVENTIONS: The treatment regimen commenced with lamivudine (LAM) for the initial 8 weeks, followed by the addition of interferon α (IFNα) after 1 year of age. At 2 years old, LAM was substituted with entecavir, and at 3 years old, IFNα was replaced with pegylated interferon α (PEG IFNα).

OUTCOMES: After 8 weeks of LAM monotherapy, Liu XX experienced hepatitis B e antigen loss. Subsequently, after 36 weeks of IFNα add-on therapy, hepatitis B virus DNA became undetectable, and after 48 weeks of switching to PEG IFNα treatment, hepatitis B surface antigen loss was observed. Remarkably, following 50 weeks of drug discontinuation, the child remained functionally cured.

LESSONS: Chronic hepatitis B virus-infected infants and young children can achieve durable functional cure with PEG IFNα-based individualized therapy. This case provides a valuable reference for the diagnosis and treatment of such patients.