Biliary epithelial changes in pediatric autoimmune hepatitis with normal cholangiography: diagnostic caution for...

Area of Science:

• Pediatric Gastroenterology
• Hepatology
• Autoimmune Diseases

Background:

• Autoimmune hepatitis (AIH) and autoimmune tiểu quản xơ gan (ASC) present diagnostic challenges in pediatric populations.
• Distinguishing between small-duct ASC and AIH can be particularly difficult, especially when initial cholangiography is normal.
• Biliary epithelial injury markers, such as mucinous metaplasia, can complicate the diagnosis but are not solely diagnostic of ASC.

Purpose of the Study:

• To describe a challenging pediatric case at the intersection of AIH and ASC.
• To emphasize the diagnostic difficulties in differentiating these conditions in children.
• To underscore the importance of careful monitoring and surveillance in suspected AIH cases with potential biliary involvement.

Main Methods:

• Case report of a 7.5-year-old boy with persistent jaundice and elevated transaminases.
• Utilized serological markers (ANA, p-ANCA), liver function tests, ceruloplasmin, and 24-hour urinary copper levels.
• Performed magnetic resonance cholangiography and liver biopsy for histopathological examination.

Main Results:

• The patient presented with features suggestive of AIH, including interface hepatitis and positive autoantibodies (ANA, p-ANCA).
• Liver biopsy showed interface hepatitis with portal lymphoplasmacytic infiltrates, bridging fibrosis, and mucinous metaplasia of bile ducts.
• Treatment with corticosteroids and azathioprine led to sustained normalization of transaminases.

Conclusions:

• AIH and ASC exist on a diagnostic spectrum in children, requiring careful evaluation.
• The presence of biliary epithelial injury and p-ANCA positivity in AIH may suggest an overlap syndrome but does not confirm ASC.
• In children with AIH and initially normal cholangiography, continued biochemical and radiological surveillance is essential for guiding long-term management.