Appendicitis is also known as a perforated or ruptured appendix. It is a serious infection of the appendix which is a small finger-like tube located where small and large intestine join. Symptoms often start with abdominal pain that occurs near the belly button or lower right. Patients also experience nausea, vomiting, loss of appetite, low-grade fever, constipation and abdominal swelling. Almost half of patients with appendicitis feel abdominal pain that moves rapidly to the lower right. If appendicitis is now treated right away, the appendix will likely burst, which then spreads infection throughout the abdomen, which is a dangerous condition called peritonitis.