A new, simple marker for predicting complicated appendicitis in patients with normal white blood cell count indicator; LUC %

BACKGROUND: The aim of this study was to investigate the ability of a new marker that could be easily obtained to differentiate between complicated and uncomplicated appendicitis in a patients with a white blood cell (WBC) count within the normal range. METHODS: The patients who underwent surgery with histopathologically proven acute appendicitis (AA) between January 2021 and October 2022 were evaluated retrospectively. Patients were classified into two groups as uncomplicated and complicated appendicitis, based on the surgical and histopathological findings. Groups were compared in terms of laboratory parameters at the time of hospital admission. RESULTS: During the study period, 2589 patients underwent an appendectomy, among these 612 patients who had a WBC count within the normal range at the time of admission were analyzed. Uncomplicated appendicitis was detected in 79.6% of the patients and complicated appendicitis in 20.4%. Neutrophil%, neutrophil-to-lymphocyte ratio, C-reactive protein, and total bilirubin levels were significantly higher, whereas lymphocyte%, lymphocyte count, lymphocyte-to-monocyte ratio, sodium levels, and large unstained cells (LUC)% were significantly lower in patients with complicated appendicitis. Multiple logistic regression analysis revealed that lower LUC% (Odds Ratio [OR]: 0.45; 95% Confidence Intervals [CI]: 1.08–2.09; P=0.01) and higher total bilirubin levels (OR: 1.50; 95% CI: 1.08–2.09; P=0.01) were independent risk factors for complicated appendicitis. CONCLUSION: In patients with a diagnosis of AA with a normal WBC value, LUC% obtained from the complete blood count can be used as a new parameter predicting the diagnosis of complicated appendicitis.