Most common between 9-12yr
Perforation rate 90% in children <4yr
NPV of 98% achieved if:
Lack of nausea (or emesis or anorexia)
Lack of maximal TTP in the RLQ
Lack of neutrophil count > 6750
Lack of nausea (or emesis or anorexia)
Lack of maximal TTP in the RLQ
Lack of neutrophil count > 6750
Appendicitis 
Emergent
Cervicitis
Necrotizing Enterocolitis
Uvulitis
Volvulus
Orchitis
Testicular torsion