Forme fruste choledochal cyst (FFCC) is one of the diverse types of choledochal cyst with little or no dilatation of the extrahepatic bile duct (EHBD). It is considered that FFCC has to do with the pancreatobiliary malunion (PBM). In children, 3 to 6 millimeters of EHBD is assumed to be normal. Even though there is no clear-cut definition, FFCC is likely to be associated with bile duct dilatation less than 10 millimeters. Almost all cases have PBMs and symptoms of the pancreatitis or cholangitis. We experienced a case of FFCC in a 4-year-old boy. His EHBD measures 10mm diameter. He had symptoms of pancreatitis and elevated hepatic transaminases. The pancreatobiliary common channel was 28 millimeters. He underwent EHBD resection and Roux-en-Y hepaticojejunostomy and was discharged with no specific complications.

Infantile hypertrophic pyloric stenosis (IHPS) a common childhood disorders characterized by nonbilious projectile vomiting, an olive shaped mass in the right upper quadrant of the abdomen and visible gastric peristaltic wave in the upper abdomen. Its etiology and pathogenesis are not clear but abnormal nerve distribution of the pylorus has been postulated^2-6. We performed immunocytochemical staning to the pyloric muscle from 10 IHPS and 3 controls patients, utilizing specific monoclonal antibody to NCAM(neural cell adhesion molecule). In IHPS patients, the number of NCAM protein immunoreactive nerve fibers were less than that in normal subjects. Auerbach myenteric plexuse was well developed and interbundle nerve plexuse was present but nerve fibers supplying individual muscle cells in smooth muscle bundles were poorly developed. These results indicate reduction of innervation in smooth muscles in IHPS patients that possibly contributes to the pathogenesis of IHPS.