Longitudinal Immune Phenotype Assessment and Serological Outcome in Foreign‐born Children With Chronic Hepatitis B

ABSTRACT Objectives: The aim of the study was to assess changes in clinical phenotype, and identify determinants of outcome in children with chronic hepatitis B virus (HBV) infection born in HBV‐endemic countries followed in 2 Italian tertiary care centers after immigration or adoption. Methods: A prospective observational study on hepatitis B e‐antibodies–negative chronic hepatitis B children started on 2002. Patients with liver fibrosis, or those needing antiviral treatment were excluded. Immune active patients were defined those with raised transaminases (alanine aminotransferase > 40 IU/L), immune tolerants those having normal alanine aminotransferase, both exhibiting substantial viral replication (HBV DNA >2000 IU/mL). Results: Sixty‐nine patients (44 boys, median age 4.7 years) had a median follow‐up of 53 months. At entry, 18 (26%) children were immune tolerant, 47 (68%) immune active, and 4 had indeterminant immune status. At last follow‐up, 14 (78%) of the immune‐tolerant patients remained so, whereas only 23 (49%) of the immune active children maintained their initial immune phenotype. Seroconversion to hepatitis B e antibodies (SCHBe) occurred in only 2 (11%) immune tolerants, whereas 13 (28%) immune active patients achieved SCHBe. Ethnicity was the only feature independently correlated to SCHBe: Asian origin reduced by 4.1 times the probability of SCHBe (Asian vs other; odds ratio = 0.24 [95% confidence interval = 0.07–0.76]; P = 0.016) compared to other ethnicities, whereas viral genotype did not influence the outcome. Conclusions: Ethnicity and immune status phenotype against HBV, rather than HBV genotype, are the main determinants of SCHBe in foreign‐born children with chronic HBV infection.