Introduction: Acute appendicitis is one of the most common problems requiring emergency surgery. Diagnosis is based on history, physical examination and laboratory findings. Rate of misdiagnosis of appendicitis especially in female is up to 23.2%. Some basic laboratory examinations such us white blood cell count, CRP and ESR have been suggested as aids in the diagnosis of acute appendicitis. But results are controversial
Objective: This study was designed to consideration of association rate of leukocytosis, increased CRP and ESR in acute appendicitis
Materials and Methods: In this prospective study, 158 patients were admitted with clinical diagnosis of acute appendicitis from September 2001 to March 2002 in Poursina hospital in Rasht. Blood samples for WBC, CPR and ESR were sent to the laboratory preoperatively. Then sensitivity, specificity, PPV and NPV of these tests were determined and analyzed.Results: There were 98 males (62%) and 60 females (38%). The mean age was 28.41 years (range 3 to 70 years). 146(92.4%) patients have histologically confirmed appendicitis and 12(7.6%) had normal appendix. Sensitivity, specificity, PPV and NPV for leukocytosis were in order: 84.2%, 33.3%, 93.9% and 14.8%; for increased CRP were in order 79.4%, 25%, 92.8% and 9.09%, and for increased ESR were: 69.2%, 8.3%, 90.2%, 22% in orderly. When all tests are used for diagnosis, these criteria were 54.8%, 66.6%, 95.2% and 10.8% respectively. In attention to sensitivity and value of positive (PPV) and increased WBC, CRP and ESR, it can be resulted that positivity of these tests in suspected appendicitis can strengthen the clinical diagnosis but lowered value of negative (NPV) tests showed that the negativity of each test or all tests together can not verify acute appendicitis.Conclusion: In presence of Leukocytosis, increased CPR&ESR probability of appendicitis was increased in clinically acute appendicitis. But normal value of WBC, CRP& ESR doesn't rule out acute appendicitis.