Noonan syndrome and autoimmune hepatitis: patient report and literature review.

OBJECTIVES

Noonan syndrome (NS) is a genetic disease characterized by dysregulation in the RAS/MAPK pathway. Affected individuals present peculiar physical features, short stature, and congenital cardiovascular defects. Autoimmune hepatitis is a chronic immunoinflammatory liver disease.

CASE PRESENTATION: A 17-year-old boy with NS due to PTPN11 gene variation and type 1 autoimmune hepatitis (AIH-1; biopsy proven) is described. A literature search on the association between NS and AIH1 showed additional two cases.

CONCLUSIONS

This report highlights the importance of monitoring patients with NS for signs of autoimmune diseases, mainly liver dysfunction. Precise mechanisms linking NS and AIH-1 remain unclear. Anyway, the dysregulation of the RAS/MAPK pathway may be involved. Periodic monitoring of transaminases and prompt evaluation with liver biopsy should be done to optimize diagnosis and treatment of people with NS.