The use of C-reactive protein to predict uncomplicated appendicitis and increase uptake of laparoscopy in low resource hospitals-A retrospective cohort study

Michael Brombacher; Haroon Moolla; Vimal Nair; Damian Clarke

doi:10.1002/wjs.12202

The use of C-reactive protein to predict uncomplicated appendicitis and increase uptake of laparoscopy in low resource hospitals-A retrospective cohort study

World J Surg. 2024 May 10. doi: 10.1002/wjs.12202. Online ahead of print.

Authors

Michael Brombacher^{1

2}, Haroon Moolla³, Vimal Nair¹, Damian Clarke^{4

5}

Affiliations

¹ Department of General Surgery, Cecilia Makiwane Hospital, Walter Sisulu University, Mdantsane, South Africa.
² Department of General Surgery, Livingstone Hospital, Walter Sisulu University, Gqeberha, South Africa.
³ Centre for Infectious Disease Epidemiology and Research, University of Cape Town, Rondebosch, South Africa.
⁴ Greys Hospital, University of Kwazulu Natal, Pietermaritzburg, South Africa.
⁵ University of the Witwaterstrand, Johannesburg, South Africa.

PMID: 38730515
DOI: 10.1002/wjs.12202

Abstract

Background: Acute appendicitis remains the most common surgical emergency worldwide. There has been a low uptake of laparoscopic appendicectomy in the South African public sector. Preoperative identification of cases of uncomplicated appendicitis that are amenable to a laparoscopic approach may facilitate the implementation of laparoscopic appendicectomy programs in training hospitals. With limited access to preoperative imaging, alternative strategies for this preoperative prediction are needed.

Methods: A retrospective audit of patients over the age of 12 years with a histologically confirmed diagnosis of acute appendicitis over a 5-year period was performed. Patients were categorized as uncomplicated or complicated appendicitis and C-reactive protein (CRP) and white cell count (WCC) reviewed. Receiver operating characteristics curves were constructed for these blood tests and acute appendicitis severity. Youden's J statistic was used to determine optimal cut off values for diagnosing complicated appendicitis.

Results: 358 patients had confirmed appendicitis and complete blood results. Of these, 189 (52.79%) had complicated appendicitis with a 40.22% perforation rate. Median CRP in uncomplicated and complicated groups were 68 mg/L (IQR 19-142) and 216 mg/L (IQR 103-313) with an area under the curve (AUC) of 0.75 (95% CI: 0.70-0.80). The median WCC in the two groups were 12.6 × 10⁹ cells/L (IQR 9.9-15.6) and 14.4 × 10⁹ cells/L (IQR 11.5-18.28) with an AUC of 0.61 (95% CI: 0.56-0.67). The optimal cut off value for CRP was found to be 110 mg/L with a sensitivity of 74.74% and specificity of 69.23%.

Conclusion: A cutoff value of 110 mg/dl CRP can distinguish patients with early appendicitis from those with complicated disease and when used in conjunction with clinical assessment may help identify patients in whom laparoscopic appendicectomy is appropriate.

Keywords: C‐reactive protein; appendicectomy; laparoscopic.