PROGNOSTIC UTILITY OF THE NEUTROPHIL–LYMPHOCYTE RATIO IN PREDICTING SEVERITY AND COMPLICATIONS OF ACUTE APPENDICITIS: A HOSPITAL-BASED ANALYTICAL STUDY

Abstract

Background: Acute appendicitis remains one of the most common surgical emergencies worldwide, with disease severity ranging from mild inflammation to perforation and gangrene. Early identification of patients at risk for severe or complicated appendicitis is crucial to reduce morbidity and optimize surgical decision-making. Conventional laboratory parameters such as total leukocyte count have shown inconsistent prognostic performance, necessitating evaluation of derived inflammatory markers. The neutrophil–lymphocyte ratio (NLR), obtained from routine complete blood counts, reflects systemic inflammatory response and may offer prognostic value in acute appendicitis. Objectives: To calculate the neutrophil–lymphocyte ratio manually from complete blood count parameters in patients with acute appendicitis and to assess its utility in predicting disease severity and complications based on histopathological outcomes. Methods: A hospital-based analytical study was conducted in a tertiary care teaching hospital over one year, including 71 adult patients who underwent emergency appendectomy for clinically suspected acute appendicitis. Preoperative absolute neutrophil and lymphocyte counts were obtained at admission, and NLR was calculated manually. Histopathological examination served as the reference standard and categorized appendicitis into moderate and severe forms, with complicated appendicitis defined by perforation or gangrene. Receiver operating characteristic curve analysis was used to determine the prognostic performance of NLR, and sensitivity, specificity, and area under the curve were calculated. Results: Histopathological confirmation of appendicitis was observed in 90.1% of cases, while 9.9% were early or non diagnostic. Complicated appendicitis accounted for 23.94% of cases. An NLR cut-off ≥5.7 predicted severe appendicitis with an area under the curve of 0.998, sensitivity of 96.15%, and specificity of 100%. An NLR cut-off >11.6 predicted complicated appendicitis with an area under the curve of 0.991, sensitivity of 100%, and specificity of 98.18%. NLR showed limited discriminatory ability for early appendicitis. Conclusion: The neutrophil–lymphocyte ratio is a highly reliable prognostic marker for predicting severity and complications in acute appendicitis, though it has limited value in identifying early disease. Given its simplicity, low cost, and universal availability, NLR can serve as a valuable adjunct to clinical and radiological assessment for early risk stratification, particularly in resource-limited settings.