The Neutrophil–Lymphocyte Ratio and Inflammation

Acikgoz ¹ commented on our article entitled “Neutrophil-lymphocyte ratio (NLR) and carotid-intima media thickness in patients with Behçet disease without cardiovascular involvement.” ²

He concluded that although the NLR seems to be a useful inflammatory marker and predictor of the activity of Behçet disease (BD), more research is required to define its exact role in patient management.

Behçet disease is a chronic, inflammatory disorder, ³ and endothelial dysfunction (ED) is considered to play a major role in the pathogenesis of vasculitis and thrombosis in BD. ^4,5 Recently, several studies highlighted the relation between ED, BD, and inflammatory markers. ^{4,6 –9} Similarly, we reported ⁵ that patients with BD had significantly higher serum levels of endocan (as a novel endothelial inflammatory marker), and these levels correlated positively with C-reactive protein, erythrocyte sedimentation rate, and BD activity. Serum levels of endocan were higher in patients with systemic involvement. ⁵

The NLR is a readily available biomarker that conveys information about inflammatory conditions. ¹⁰ Furthermore, epidemiological studies reported that chronic inflammation measured by the NLR is related to classic risk factors such as diabetes mellitus, hypertension, ¹¹ metabolic syndrome, ¹² obesity, smoking, and elevated cholesterol values. ¹⁰ Furthermore, recent evidence reported that the NLR has a significant prognostic value for several conditions in prospective long-term studies. ¹³ Also, the NLR is influenced by several conditions including medication ¹⁴ dehydration, overhydration, diluted blood specimens, and in vitro specimen handling. ¹⁰ The NLR may change after medications, and the levels of NLR can be changed by severity of chronic diseases. ¹¹ We agree with Acikgoz that the NLR may also be related to other inflammatory markers and ED. ¹ It is also considered that NLR levels positively correlated with carotid intima–media thickness. ² So, a high NLR may be related to endothelial dysfunction and reflects BD activity. ^2,9

In conclusion, the NLR levels may reflect the severity of diseases with an inflammatory component. Conditions that are related to NLR levels should be kept in mind when NLR levels are interpreted. We need to evaluate this marker for managing and following clinical outcomes in many conditions. We suggest that the NLR should be evaluated together with clinic outcomes such as vascular involvement.