Classic triad of intussusception in infants includes?

Intussusception is the telescoping of one segment of bowel into an adjacent segment, most commonly occurring at the ileocecal junction in infants between 3 months and 3 years of age. Its classic clinical triad consists of sudden, severe colicky abdominal pain (often causing the infant to draw up the knees and cry intermittently), red currant jelly stool (which results from mucosal ischemia causing blood and mucus to mix), and a palpable sausage-shaped abdominal mass in the right upper quadrant as the intussuscepted bowel is felt on palpation. Recognizing this triad is critical because intussusception is a pediatric emergency that can progress to bowel necrosis and perforation if untreated. The first option describes a gastroenteritis-type picture with fever and watery diarrhea, which does not fit intussusception. The second option — painless rectal bleeding with weight loss and polyuria — suggests a different diagnosis such as a Meckel's diverticulum or juvenile polyp rather than intussusception. The third option of chronic constipation, abdominal distention, and clubbing is more consistent with Hirschsprung's disease or cystic fibrosis. The Dance sign, mentioned in the pyloric stenosis question, refers to an absence of bowel in the right iliac fossa seen in intussusception; however, it is not part of the classic triad of presenting symptoms. Treatment involves air or hydrostatic enema reduction, with surgery reserved for failed reduction or perforation.