| K52 | Other and unspecified noninfective gastroenteritis and colitis | NON-BILLABLE CODE |
| K52.0 | Gastroenteritis and colitis due to radiation | BILLABLE CODE |
| K52.1 | Toxic gastroenteritis and colitis | BILLABLE CODE |
| K52.2 | Allergic and dietetic gastroenteritis and colitis | NON-BILLABLE CODE |
| K52.21 | Food protein-induced enterocolitis syndrome | BILLABLE CODE |
| K52.22 | Food protein-induced enteropathy | BILLABLE CODE |
| K52.29 | Other allergic and dietetic gastroenteritis and colitis | BILLABLE CODE |
| K52.3 | Indeterminate colitis | BILLABLE CODE |
| K52.8 | Other specified noninfective gastroenteritis and colitis | NON-BILLABLE CODE |
| K52.81 | Eosinophilic gastritis or gastroenteritis | BILLABLE CODE |
| K52.83 | Microscopic colitis | NON-BILLABLE CODE |
| K52.831 | Collagenous colitis | BILLABLE CODE |
| K52.832 | Lymphocytic colitis | BILLABLE CODE |
| K52.838 | Other microscopic colitis | BILLABLE CODE |
| K52.839 | Microscopic colitis, unspecified | BILLABLE CODE |
| K52.89 | Other specified noninfective gastroenteritis and colitis | BILLABLE CODE |
| K52.9 | Noninfective gastroenteritis and colitis, unspecified | BILLABLE CODE |
