Utility of biomarkers in predicting complicated appendicitis: can immature granulocyte percentage and C-reactive protein be used?

Postgrad Med. 2021 Sep;133(7):817-821. doi: 10.1080/00325481.2021.1948306. Epub 2021 Jul 9.


Background: Acute appendicitis is the most common reason for abdominal surgery in children. The aim of this study was to evaluate the utility of biomarkers in predicting complicated appendicitis (CA).

Methods: Patients having a diagnosis of acute appendicitis who underwent operations were retrospectively determined, and the utility of biomarkers in predicting CA was evaluated.

Results: A total of 251 patients were included in the study. The mean age was 130.9 ± 48.8 months, 148 of the cases (59%) were simple appendicitis, and 103 (41%) were CA. The C-reactive protein (CRP) levels, immature granulocyte (IG) percentage, white blood cell counts, and absolute neutrophil counts were significantly higher in the CA patients. The bilirubin levels and neutrophil to lymphocyte ratios were not useful for predicting CA. The best area under the curve (AUC) values to predict CA were with the IG percentage and CRP level (0.82), the IG percentage [odds ratio (OR) 9.36, 95% CI (4.94-17.75), p < 0.001] and CRP [OR 8.42, 95% CI (4.72-15.02), p < 0.001] were the best marker in predicting CA. The sensitivity of the IG percentage and CRP level were higher than other markers.

Conclusion: To predict CA, the best AUC values were associated with the IG percentage and the CRP level. Because it is easy, fast to measure, does not require taking extra blood, and does not lead to additional costs, IG percentage may be preferred in the diagnosis of patients with CA.

Keywords: Acute appendicitis; biomarkers; complicated appendicitis; immature granulocyte.

MeSH terms

  • Acute Disease
  • Adolescent
  • Age Factors
  • Appendicitis / blood*
  • Appendicitis / physiopathology*
  • Biomarkers
  • C-Reactive Protein / analysis*
  • Child
  • Female
  • Granulocytes / cytology*
  • Hospitals, Pediatric
  • Humans
  • Length of Stay
  • Male
  • Retrospective Studies
  • Sex Factors
  • Turkey


  • Biomarkers
  • C-Reactive Protein