children younger than years of age Predictably, the diagnosis is very difficult in children younger than years of age The emergency physician must accurately evaluate the child and promptly consult a surgeon when the diagnosis is clear or when appendicitis cannot be safely ruled out Such consultation is especially urgent in younger children, in whom perforation can occur within to 24 hours of the onset of symptoms Usually the child with appendicitis initially complains of poorly defined and poorly localized midabdominal or periumbilical pain Unfortunately, this symptom is common to many other nonsurgical intraabdominal problems In the young and, to a lesser extent, the older child, vomiting and a low-grade fever often occur Characteristically, the pain then migrates to the right lower quadrant ( Table 116.1 )