Kawasaki disease with dilatation of the common bile duct: A case report and review of literature

Background Kawasaki disease (KD), which was first described by Tomisaku Kawasaki in 1967, is a syndrome that results in acute systemic vasculitis, affecting mainly infants and children, and is a major cause of acquired heart disease in developed countries. KD is diagnosed based on certain characteristic symptoms and echocardiogram results. It has been reported that neck and abdominal ultrasound is also reliable diagnostic method. Nevertheless, abdominal ultrasound is not a routine procedure in KD. Moreover, dilatation of the common bile duct (CBD) has been rarely reported in previous cases. Case presentation: A 4-year-old boy presented with fever and markedly high transaminase level (AST, 5,323 U/L, ALT, 1,554 U/L). The patient was diagnosed as having KD based on characteristic symptoms and echocardiogram findings. Neck and abdominal ultrasound revealed dilatation of the CBD as well as cervical lymphadenopathy resembling a cluster of grapes, thickening of the gallbladder wall, and increased periportal echogenicity throughout the liver parenchyma. The patient received initial treatment with intravenous immunoglobulin (IVIG) at day 4 of fever, following which, transaminase level decreased. The patient received second-line treatment with IVIG and prednisolone because of recurrent fever on day 6. Dilatation of the CBD was improved from 6.6 mm on day 4 to 3.1 mm on day 8. Although re-dilatation was observed, it gradually diminished and normalized (4.3 mm on day 28, 4.0 mm on day 63, 3.3 mm on day 105, and 2.8 mm on day 182). Conclusion This case highlights the usefulness of abdominal ultrasound and the importance of considering dilatation of the CBD as one of the complications of KD. Because abdominal ultrasound is not a routine procedure in KD, it is possible that dilatation of the CBD in KD is quite latent if not investigated thoroughly. Further prospective studies to support these findings are warranted.