Appendicitis can be classified into two types, typical and atypical. The pain of typical acute appendicitis usually starts centrally (periumbilical) before localising to the right iliac fossa (the lower right side of the abdomen). There is usually associated loss of appetite (anorexia) and fever. Nausea, or vomiting may or may not occur. These classic signs and symptoms are more likely in younger patients. Older patients (beyond their teenage years) may present with only one or two. Diagnosis is easier in typical acute appendicitis and surgery removes a swollen appendix with little or no suppuration (pus) if operated early (within 24 hours of onset).