The diagnostic value of leucocytes and C- reactive protein in acute appendisitis

Background: Abdominal pain is one of the most common causes of emergency department (ED) presentations that leads invasive procedures due to a possible acute appendicitis even negative laparotomies in so many patients. The present study aimed to determine the value of leucocyte and C-reactive protein (CRP) combination in the diagnosis of acute appendicitis. Methods: This retrospective study was between 01.01.2014 and 03.03.2016 in an ED of a tertiary care hospital. The study data was obtained by using the computerized database of the hospital. The study population was composed of patients over 18 years whom leucocyte count, CRP and pelvic ultrasound were obtained. The final diagnosis was achieved by pathology results, hospital discharge diagnosis and telephone follow-up. Results: A total of 2430 patients were included into the study. The mean age of study patients was 36.7±15.5 and 27% of them (n=658) was male. The sensitivity and specificity of leucocyte count and CRP was as follows: 63,9% (95% CI: 57% to 70%), 64,9% (95% CI: 63% to 67%), 80% (95% CI: 74% to 85%), 39,7% (38% to 42%), respectively. The sensitivity, specificity, positive likelihood ratio and negative likelihood ratio of the combination of leucocyte count and CRP was as follows: 92,6% (95% CI: 88% to 96%), 28,6% (9% CI: 27% to 31%), 1,3 (955 CI: 1,24 to 1,36), 0,26 (95% CI: 0,16 to 0,41), respectively. Conclusion: Leucocyte count and CRP has insufficient diagnostic power for ruling in or ruling out acute appendicitis. Despite the improvement of diagnostic utility by combining these markers, physicians should perform further analysis in patients with a high pre-test probability. Key words: Emergency department, leucocyte, C-reactive protein, acute appendicitis.