The role of hematological parameters in distinguishing acute appendicitis from lymphoid hyperplasia

BACKGROUND: One of the most misdiagnosed appendicular pathologies is lymphoid hyperplasia (LH) that can be managed conservatively when identified early and is self-limiting. The aim of this retrospective study was to compare acute appendicitis (AA) with LH in terms of hematological parameters to determine whether there is a hematological predictor to distinguish the two diseases. METHODS: Complete blood cell counts of patients with AA were compared with those having LH. RESULTS: One-hundred-ninety-five patients (118 male/77 female) underwent appendectomy. Histopathological examination revealed acute AA in 161 patients (82.6%), and negative appendectomy (NA) in 19 patients (9.7%). Of the NA specimens, 16 were LH (8.2%). Thirteen patients (6.7%) had AA with simultaneous LH. White blood cell count (p=0.030, neutrophil (p=0.009), neutrophil percentage (p=0.009), and neutrophil/lymphocyte ratio (p=0.007) were significantly higher in AA whereas lymphocyte count (p=0.027), lymphocyte percentage (p=0.006) were significantly higher in LH. Multi logistic regression analysis revealed white blood cell count as the only independent predictor in distinguishing AA from LH with a 69.1% sensitivity, 80.0% specificity, 77.5% positive predictive value, and 72.1% negative predictive value. The cut-off value for white blood cell count was 11.3 Ku/L, and every one unit (1000/mm(3)) increase in white blood cell count raises the risk of AA by 1.24 times, while values below this value will increase the likelihood of LH. CONCLUSION: The most predictive complete blood count parameter in distinguishing LH from AA appears to be as white blood cell count.