Causes

• Anal Fissure: If no associated diarrhea, more than 90% of children with blood in the stools have an anal fissure. Anal fissures usually are caused by passage of a large or hard bowel movement.
• If associated diarrhea, most of the children have Shigella, Salmonella or Campylobacter infections.
• Some foods (e.g., tomatoes) and some medicines can also cause red-colored stools that look like blood.