The accuracy of white cell count and C-reactive protein in diagnosing acute appendicitis at a tertiary hospital

Abstract

Background: Diagnostic accuracy in acute appendicitis (AA) may be improved by using inflammatory markers. This study assessed the reliability of inflammatory markers in diagnosing AA in our patient population.

Methods: A retrospective cross-sectional study was conducted at King Edward Hospital (KEH) from January 2020 to June 2021. Data was collected on all patients with AA who underwent appendicectomy. Variables of age, gender, comorbidities, HIV status Alvarado score histology, C-reactive protein (CRP), and white cell count (WCC) were reviewed. A p-value of < 0.05 is deemed as statistically significant.

Results: The study cohort was comprised of 150 patients – 58(39%) females and 92(61%) males. Thirty-two (21.3%) patients had a normal appendix, of whom 19 had a normal WCC. The majority of patients 80 (53.3%) had inflamed appendix, and 38 (25.3%) had ruptured appendix. The sensitivity and specificity of WCC and the CRP were 81% and 46% and 100% and 18.6% respectively. No patient with a ruptured appendix had normal CRP. The CRP correlated with the ruptured appendix with a median of 141.5 and, p-value of 0.01. The level of WCC and the presence of a ruptured appendix had a significant correlation with a p-value of 0.002, median of 15.2.

Conclusion: A combination of WCC and CRP tests improves the diagnostic accuracy. There is a correlation between CRP level and ruptured appendicitis. In our setting, AA is likely to present late once it has already ruptured. The reasons behind this late presentation need to be explored and addressed.