Peroperative Findings in Acute Appendicitis: Relationship with Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios.

Objective: To ascertain whether the platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) are reliable diagnostic tools for acute appendicitis.

Study design: An analytical study. Place and Duration of the Study: Department of General and Laparoscopic Surgery, Sheikh Khalifa Bin Zayed Al Nahyan Hospital, Muzaffarabad, Pakistan, from January to June 2022.

Methodology: This study was conducted using consecutive sampling of patients aged ≥16 years. Admission haemogram was used to calculate the NLR and PLR. These ratios were compared with peroperative findings regarding the stage of inflammation in the appendix. Sensitivity, specificity, and accuracy rates were compared and evaluated using a non-parametric (empirical) method for receiver operating characteristic curve analysis.

Results: The median age of patients was 26 years, with a male-to-female ratio of 1:1.03. NLR had a sensitivity of 76.9%, a specificity of 93.3%, a negative predictive value (NPV) of 94.2%, and an accuracy of 70.2% in separating complicated from uncomplicated appendicitis. Moreover, it had a sensitivity of 73%, a specificity of 100%, an NPV of 98%, and an accuracy of 73.03% in separating non-inflamed appendix from uncomplicated appendicitis. PLR did not show any significant differentiation between non-inflamed appendix and uncomplicated appendicitis (p = 0.8), and its accuracy for differentiating complicated from uncomplicated appendicitis was also low, that is, 48.2%.

Conclusion: NLR is a helpful diagnostic tool that can predict uncomplicated and complicated appendicitis and differentiate between them. However, relying solely on NLR for diagnosing appendicitis is not advisable. PLR does not have similar predictability. More research needs to be done to find additional biomarkers for NLR and PLR to improve their predictability as a diagnostic tool.

Key words: Appendicitis, Biomarker, Negative appendectomy, Neutrophil-to-lymphocyte ratio, Perforation, Platelet-to-lymphocyte ratio, Sensitivity, Specificity.