The diagnosis of acute appendicitis is difficult and despite important advances in medical sciences, detailed patient questioning and precise medical examination are the main keystones of the diagnosis of acute appendicitis and up to now, results still unsatisfactory.

Acute appendicitis is the most common surgical emergency and the most common source of community-acquired intra-abdominal infections. The lack of accuracy in the diagnosis of acute appendicitis yields often to two types of outcomes: a delay in diagnosis leads to perforation and peritonitis in up to 15% of the cases and unnecessary appendectomy is associated with post-operative complications such as wound infection and adhesions. CRP is an acute phase protein that is often used by many surgeons as a diagnostic marker of acute appendicitis. During the evaluation of patients with possible appendicitis in the emergency department (ED), repeated physical examination of the abdomen may provide further information about the decision making. However, the role of repeated laboratory examinations is not proven.

The purpose of this study was to investigate whether repeated serum CRP measures could be useful to predict acute appendicitis, after 3 hours of observation, in comparison with the histopathological findings.

Inclusion Criteria:

• age > 8 year old
• clinical suspicion of acute appendicitis including the presence of direct tenderness in the right lower quadrant, percussion and rebound tenderness, pyrexia, anorexia, nausea and vomiting.

Exclusion Criteria:

• patients receiving anti coagulants
• pregnant women
• patients using antibiotics during the study period.

All patients presenting to the Fattouma Bourguiba University hospital with an equivocal diagnosis of acute appendicitis. The clinical suspiscion of appendicitis was made based on anamnestic and physical examination findings.