Timeline of Progression From Autoimmune Hepatitis to Overlap Syndrome in a 9-Year-Old Pediatric Patient

Abstract

A 9 year old male presented with fatigue and elevated liver function tests including; Alkaline Phosphatase at 430 U/L, AST at 888 U/L, and ALT at 1300 U/L. The total bilirubin was normal at 0.5 mg/dL. Smooth Muscle antibody IgG was elevated at 99 units, gliadin IgG elevated at 21 units and liver kidney microsomal (LKM) antybody was normal. An initial MRCP was normal.Figure 1Figure 2A liver biopsy revealed moderate interface hepatitis with lobular disarray, consistent with autoimmune hepatitis (AIH), Grade 3, Stage III. Negative for cirrhosis and malignancy. The patient initially responded well to glucocorticoid therapy with AST decreasing from 887 U/L to 54 U/L over a 6 week period. His ALT also decreased from 1316 U/L to 103 U/L over a that same time frame. The patient subsequently developed loss of response to glucocorticoid therapy with increasing GGT and transaminases. The patient did not respond to the addition of immunomodulator (6-MP) despite therapeutic levels. Repeat MRCP revealed a new finding of mild intra and extrahepatic biliary dilations with irregularity and nodularity of the intrahepatic bile ducts. The walls of the common hepatic and bile ducts and the proximal central bile ducts were mildly thickened with slight enhancement. The appearance was consistent with cholangitis (Primary Sclerosing Cholangitis). The child was diagnosed with AIH-PSC Overlap Syndrome. The patient was than treated with Vancomycin 125mg TID x 4 weeks, then BID thereafter. The patient had a prompt response with improving (AST) from 164U/L to 25 U/L and (ALT) from 361 U/L to 39 U/L in 2 months. The GGT also normalized. Patient was successfully weaned off glucocorticoid and is currently in remission over the past 4 months. Conclusion: AIH and PSC may be sequential in their occurrence in children. Our case documents the sequential nature of this overlap syndrome. Sequential progression to PSC or overlap syndrome should be considered in children with AIH who lose response to standard therapy.