What is one of the hallmark symptoms of ulcerative colitis?

Bloody diarrhea is indeed one of the hallmark symptoms of ulcerative colitis, a type of inflammatory bowel disease (IBD) that primarily affects the colon and rectum. This condition is characterized by inflammation of the colonic mucosa, which leads to ulcer formation. The inflammation and ulceration can cause bleeding, resulting in the presence of blood in the stool. Patients often experience episodes of diarrhea mixed with blood, which distinguishes ulcerative colitis from other gastrointestinal conditions.

This symptom is particularly significant as it not only indicates active inflammation but can also lead to further complications if not managed appropriately. Bloody diarrhea is often accompanied by other symptoms such as abdominal pain and cramping, but the presence of blood is a defining characteristic that links this condition directly to ulcerative colitis.

Other options such as constipation and weight gain are typically not associated with ulcerative colitis, as affected individuals usually face frequent, loose, or watery stools. Abdominal distension can occur due to bloating or gas, but it is also less specific to ulcerative colitis compared to the definitive symptom of bloody diarrhea. Thus, the association of bloody diarrhea with ulcerative colitis emphasizes its role as a critical symptom in the diagnosis and management of this disease.