Neutrophil to Lymphocyte Ratio: An Emerging Marker of the Relationships between the Immune System and Diseases

• Published in: International journal of molecular sciences Vol. 23; no. 7; p. 3636
• Main Authors: Buonacera, Agata, Stancanelli, Benedetta, Colaci, Michele, Malatino, Lorenzo
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.03.2022; MDPI
• Subjects: Adaptive immunity; Biomarkers; Blood; Catecholamines; COVID-19; Cytokines; Disease; Humans; Immune system; Infections; Lymphocyte Count; Lymphocytes; Medical prognosis; Mortality; Neutrophils; Physiology; Pneumonia; Retrospective Studies; Review; Sepsis; coronavirus disease-2019 (COVID-19); intensive care unit (ICU); marker; mortality; neutrophil-to-lymphocyte ratio (NLR); prognosis; sepsis
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms23073636

Over the last 10 years, the evaluation of the neutrophil-to-lymphocyte ratio (NLR) as an emerging marker of diseases has become a compelling field of bio-medical research. Although a precise and unique cut-off value has not been yet found, its role as a flag of immune system homeostasis is well established. NLR has a well-known prognostic value and independently correlates with mortality in the general population and in several specific subsets of disease (sepsis, pneumonia, COVID-19, cancer, etc.). Moreover, NLR was recently considered as part of the decision-making processes concerning the admission/recovery of patients with COVID-19 pneumonia. This review aims to provide an overview of the main use of this biomarker, focusing on the pathophysiology and the molecular basis underlying its central role as a reliable mirror of inflammatory status and adaptive immunity.