The Monocyte-to-Lymphocyte Ratio on the 6th Day Postburn Is Associated with Clinical Outcome of Severe Burns.

Objective: As an immune/inflammatory indicator, the application of monocyte-lymphocyte ratio (MLR) in the treatment of severe burns is lacking. The aim of this study was to investigate the dynamic changes of the MLR value in the early stage of severe burns and its clinical value.

Methods: This is a 5-year retrospective cohort study involving 100 patients with severe burns (II-III degree and total body surface area (TBSA) >50%), in which the lymphocyte count, monocyte count, MLR value, C-reactive protein (CRP), creatinine (Scr), and capillary leakage index (CLI) were evaluated soon after injury, and 30-day mortality rates were investigated.

Results: The MLR values in non-survivors with severe burns were higher than those in survivors in the first two days after injury, while the values on the 3^rd, 5^th, 6^th and 7^th day after injury were lower than those in survivors. The differences between the 6^th and 7^th days after injury were statistically significant. According to the results of logistic and Cox regression analysis, the MLR values on the 6^th day after injury were independent predictors of mortality, and the area under the ROC curve of the 6^th day MLR for severe burn-delayed death prediction was 0.658 (95% confidence interval, 0.541-0.774), and the optimal cut-off value was 0.991. The 30-day mortality rates differed significantly between the MLR6 ≥0.991 group and the MLR6≤0.991 group (P<0.05). Within one week after injury, the MLR values were negatively correlated with Scr, CRP and CLI levels for severe burns.

Conclusions: Our results revealed the dynamic characteristics of the MLR value in the early stage of severe burns, reflecting important changes in the immune/inflammatory related stress response soon after injury, low MLR level was associated with the worsening of disease condition.