Background: Acute appendicitis is the most common surgical emergency in pediatrics. In this study, we aimed to evaluate the diagnostic value of D-dimer in differentiating between simple and other severe acute appendicitis in children combined with white blood cell (WBC) count, neutrophil percentage, and C-reactive protein (CRP).
Methods: A retrospective study enrolled 327 consecutive patients who underwent appendectomy for acute appendicitis (aged 13 days to 14 years) in Qingdao Women & Children’s Hospital from Jan 2013 to Dec 2014. WBC count, neutrophil percentage, CRP, and D-dimer levels were measured. Descriptive analyses, Student’s t-test, and receiver operating characteristic (ROC) analyses were used to quantify the correlation between D-dimer level and the severity of appendicitis and to evaluate the differential diagnostic value of D-dimer combined with WBC count, neutrophil percentage and CRP between simple and other severe appendicitis.
Results: Compared with simple appendicitis, WBC count, neutrophil percentage, CRP, and D-dimer levels were all significantly higher in other severe appendicitis (p < 0.01). Both CRP and D-dimer levels were positively correlated with the severity of disease. In differentiating between simple and other severe appendicitis, CRP (area under the ROC curve (AUC): 0.841) showed the highest sensitivity (80.7%) and the highest negative predictive value (NPV) (60.0%), while D-dimer (AUC: 0.793) showed the highest specificity (90.0%) and the highest positive predictive value (PPV) (94.9%). Combined CRP and D-dimer had a sensitivity, specificity, PPV, NPV, and accuracy of 87.5%, 94.6%, 97.8%, 72.9%, and 89.4%, respectively.
Conclusions: CRP and D-dimer levels are positively correlated with the severity of acute appendicitis in children. Combined CRP and D-dimer are identified as suitable diagnostic markers for differentiating between simple and other severe appendicitis, which will provide important guidance for clinicians to determine the follow-up management of acute appendicitis.