Mega-choledochus - Is it pathologically Similar to Megacolon?

The traditional classification and etiopathogenic theory of choledochal cyst (CDC) has recently been challenged. A 16-month-old baby girl presented with jaundice, abdominal distention and clay colored stools for 2 weeks. Investigations revealed a Type IVA CDC. At laparotomy, a hugely distended biliary apparatus with an apparent blind distal end was noted. Excision of the CDC and Roux-en-Y hepatico-jejunostomy was performed. Her recovery is marked by a transient ascites for just 2 weeks. Histopathology of the excised distal bile duct showed hypertrophied nerve bundles similar to Hirschsprung's disease. Ultrasonography after 4 mo of surgery revealed complete regression of intra-hepatic duct dilation. From these, it appears that Todani Type I and Type IVa CDC may be just variations of the same disease.