The Diagnostic Value of Laboratory Tests in Acute Appendicitis

Lee, In Kyu; Sung, Bu Hong

Abstract

PURPOSE
Acute appendicitis has atypical clinical findings that make accurate preoperative diagnosis difficult. The aim of this study was to investigate the usefulness of laboratory analyses, especially total leukocyte count (WBC) and neutrophil count, C-reactive protein (CRP) in the diagnosis of acute appendicitis. METHODS: Sixty-nine patients who visited to the Department of Surgery, Sangju St. Mary's hospital with the diagnosis suspected acute appendicitis were studied. WBC, neutrophil count, CRP, and erythrocyte sedimentation rate (ESR) were analysed. Surgery for acute appendicitis was performed in fifty-four patients. According to histopathological findings of the appendix, the patients were divided into four groups: complicated (20 patients with perforated & gangrenous type), suppurative (9 patients), phlegmonous (25 patients), and normal (15 patients). The sensitivity and specificity of the laboratory tests in the diagnosis of acute appendicitis were calculated. RESULTS: The sensitivity of WBC>10, 000/mm3, neutrophil count>70% or >7, 000/mm3, and CRP>12 mg/L in acute appendicitis was 68.5%, 85.1%, and 74.0%, and the specificity was 86.0%, 73.3%, and 80.0% respectively. The combination of neutrophil count or CRP was 94.4% sensitivity. The severity of appendicitis had positive relationship with WBC, neutrophil count, and CRP (P=0.0001, P<0.0001, and P= 0.0014, respectively). The appendicitis and normal groups were significantly different in WBC, neutrophil count, and CRP (P<0.05). CONCLUSION: WBC, neutrophil count, and CRP have diagnostic value among the myriad causes of right lower quadrant abdominal pain and show a positive relationship with the severity of appendicitis.