| Q40 | Other congenital malformations of upper alimentary tract |
| Q40.0 | Congenital hypertrophic pyloric stenosis |
| Q40.1 | Congenital hiatus hernia |
| Q40.2 | Other specified congenital malformations of stomach |
| Q40.3 | Congenital malformation of stomach, unspecified |
| Q40.8 | Other specified congenital malformations of upper alimentary tract |
| Q40.9 | Congenital malformation of upper alimentary tract, unspecified |
| Q41 | Congenital absence, atresia and stenosis of small intestine |
| Q41.0 | Congenital absence, atresia and stenosis of duodenum |
| Q41.1 | Congenital absence, atresia and stenosis of jejunum |
| Q41.2 | Congenital absence, atresia and stenosis of ileum |
| Q41.8 | Congenital absence, atresia and stenosis of other specified parts of small intestine |
| Q41.9 | Congenital absence, atresia and stenosis of small intestine, part unspecified |
| Q42 | Congenital absence, atresia and stenosis of large intestine |
| Q42.0 | Congenital absence, atresia and stenosis of rectum with fistula |
| Q42.1 | Congenital absence, atresia and stenosis of rectum without fistula |
| Q42.2 | Congenital absence, atresia and stenosis of anus with fistula |
| Q42.3 | Congenital absence, atresia and stenosis of anus without fistula |
| Q42.8 | Congenital absence, atresia and stenosis of other parts of large intestine |
| Q42.9 | Congenital absence, atresia and stenosis of large intestine, part unspecified |
| Q43 | Other congenital malformations of intestine |
| Q43.0 | Meckel's diverticulum (displaced) (hypertrophic) |
| Q43.1 | Hirschsprung's disease |
| Q43.2 | Other congenital functional disorders of colon |
| Q43.3 | Congenital malformations of intestinal fixation |
| Q43.4 | Duplication of intestine |
| Q43.5 | Ectopic anus |
| Q43.6 | Congenital fistula of rectum and anus |
| Q43.7 | Persistent cloaca |
| Q43.8 | Other specified congenital malformations of intestine |
| Q43.9 | Congenital malformation of intestine, unspecified |
| Q44 | Congenital malformations of gallbladder, bile ducts and liver |
| Q44.0 | Agenesis, aplasia and hypoplasia of gallbladder |
| Q44.1 | Other congenital malformations of gallbladder |
| Q44.2 | Atresia of bile ducts |
| Q44.3 | Congenital stenosis and stricture of bile ducts |
| Q44.4 | Choledochal cyst |
| Q44.5 | Other congenital malformations of bile ducts |
| Q44.6 | Cystic disease of liver |
| Q44.7 | Other congenital malformations of liver |
| Q45 | Other congenital malformations of digestive system |
| Q45.0 | Agenesis, aplasia and hypoplasia of pancreas |
| Q45.1 | Annular pancreas |
| Q45.2 | Congenital pancreatic cyst |
| Q45.3 | Other congenital malformations of pancreas and pancreatic duct |
| Q45.8 | Other specified congenital malformations of digestive system |
| Q45.9 | Congenital malformation of digestive system, unspecified |