Effect of combined colchicine-corticosteroid treatment on neutrophil/lymphocyte ratio: a predictive marker in Behcet disease activity

Background and aims Behcet's disease (BD) is an auto-immune vasculitis, characterized by episodic inflammation of multiple organs. The neutrophil to lymphocyte ratio (NLR) is used as a marker of inflammation in several diseases nowadays. While nitric oxide (NO) seem to be involved in BD pathogenicity. Our study aims to investigate the NLR as an inflammatory marker of BD activity as well as to evaluate the relationship between the NO production and NLR in Algerian BD patients with different clinical manifestations before and under colchicine + corticosteroid treatment. Methods For this purpose, we evaluated the NLR as the ratio of neutrophil count to lymphocyte count in naive and treated active BD patients with different clinical manifestations and in inactive ones. Furthermore, we assessed NO production by the Griess' method in the same patients. Additionally, we evaluated in vivo interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) levels using ELISA. Results and discussion Our results indicate that the NLR and nitrite levels were higher in naive active BD patients. Interestingly, this high ratio and NO production differed according to the clinical manifestations and was associated with an increased risk of mucocutaneous and vascular involvement. Importantly, in treated BD patients NLR was higher in active patients especially in those with mucocutaneous involvement while increased nitrites levels were regardless of the clinical manifestations studied. Both NLR and NO production decreased in these treated active patients. In addition, IL-4 production differed according to the clinical manifestations studied contrary to the IFN-gamma production. Conclusion Collectively our results suggest that the NLR is a potential marker of BD activity in Algerian patients, predicting the disease severity. Moreover, the positive relationship between the NLR and NO production is related to an increased risk of mucocutaneous lesions and vascular involvement. Thus, the application of these two accessible tools could be benefit for the clinical prognosis and treatment of BD.