The use of Neutrophil – Lymphocyte Ratio (NLR) as a potential biomarker to predict the prognosis of Ludwig's angina patients

Abstract

Background: Ludwig's angina is an infection of the submandibular cavity in the form of cellulitis that is rapidly progressive and potentially life-threatening. Neutrophils and lymphocytes play an important role in this infection process. Neutrophil-lymphocyte Ratio (NLR) is a simple biomarker to evaluate systemic inflammation. We aimed to determine the association between NLR and various prognostic parameters in patients with Ludwig's Angina. Methods: A retrospective cohort study was conducted using medical records of Ludwig's Angina patients treated at Dr. Soetomo General Hospital, Surabaya, Indonesia, between January 2018 – December 2021. The NLR cut-off value was calculated using the receiver operating characteristics (ROC) curve. The association between NLR with severity, length of stay (LoS), and mortality were analyzed using SPSS version 23 for Windows. Results: We recruited a total of 96 patients. NLR values are divided categorically into low NLR and high NLR using a cut-off value of 16.86. There were 49 patients (51%) with low NLR and 47 (49%) with high NLR. There was a significant relationship between NLR with severity, LoS, and mortality in Ludwig’s angina patients (p=0.032, p=0.002, and p=0.026, respectively). According to a survival study, the high NLR group's survival rate was significantly lower than the low NLR group's (p=0.009). Conclusion: There was a significant relationship between NLR severity grading, survival, and the length of stay in patients with Ludwig's Angina.