Which of the following symptoms is a common presentation of intussusception in children?

Intussusception is a serious condition in children where a part of the intestine telescopes into an adjacent segment, leading to obstruction and potential ischemia. One of the classic symptoms associated with intussusception is rectal bleeding, often described as "currant jelly" stools due to the presence of blood and mucus. This occurs because the compromised blood supply to the affected segment of the bowel can result in mucosal sloughing, leading to bleeding.

While abdominal tenderness can be a symptom, it is not as specific or characteristic for intussusception compared to rectal bleeding. Severe dehydration may indeed occur due to prolonged vomiting or inability to eat, but it's not a primary symptom of the condition itself. Weight gain is generally not associated with intussusception, as the condition typically leads to other symptoms that are indicative of gastrointestinal distress, such as pain, vomiting, and decreased appetite. Thus, rectal bleeding is recognized as a crucial sign of intussusception in pediatric patients.