- 530 Diseases of esophagus
- 531 Gastric ulcer
- 532 Duodenal ulcer
- 533 Peptic ulcer site unspecified
- 534 Gastrojejunal ulcer
- 535 Gastritis and duodenitis
- 536 Disorders of function of stomach
- 537 Other disorders of stomach and duodenum
- 538 Gastrointestinal mucositis (ulcerative)
