Gastrointestinal Emergencies further discuss the diagnosis and management of patients with GI bleeding FIGURE 116.17 Causes of rectal bleeding in children CLINICAL PEARLS AND PITFALLS Blood per rectum can be a sign of ischemic bowel Meckel diverticulum can present with brisk, painless rectal bleeding Small amounts of blood mixed in the stool of an otherwise healthy, asymptomatic infant is generally due to allergic colitis