Chronic colitis is characterized by symptoms such as abdominal pain, diarrhea, and sometimes mucus in the stool resembling nasal discharge. These symptoms do not vary between mild or moderate to severe cases, as both mild and severe chronic colitis exhibit similar symptoms, making it impossible to distinguish between the severity from the symptoms alone. It is only possible to determine whether chronic colitis is mild or severe during a colonoscopy by observing the degree of mucosal hyperemia, edema, and erosion. Therefore, to differentiate whether chronic colitis is mild or severe, a definitive diagnosis must be made through a colonoscopy examination.