A Novel Inflammatory Marker in the Follow-up of Moderate-to-Severe Acne Vulgaris Administered Isotretinoin: Systemic Immune-Inflammation Index (SII)

Background: Systemic immune-inflammation index (SII) is calculated by multiplying the neutrophil-lymphocyte ratio (NLR) and the platelet count. In this study, we aimed to investigate the difference of SII and other inflammatory markers in patients with acne vulgaris compared to healthy controls and themselves after Oral isotretinoin (ISO) treatment. Materials and methods: In this study 190 patients with severe acne vulgaris who received at least 3 months of ISO treatment (0.5-1mg/kg/day) and 66 healthy individuals were evaluated. Hemoglobin, neutrophil, lymphocyte, monocyte, and platelet counts, mean platelet volume (MPV), Plateletcrit (PCT), NLR, platelet-lymphocyte ratio (PLR), monocyte-lymphocyte ratio (MLR), and SII were analyzed. Results: Before ISO treatment, patients with moderate-to-severe acne vulgaris had significantly higher neutrophil counts and SII levels than healthy controls (p=0.036, p=0.028; respectively). In the third month of ISO treatment, both neutrophil count and SII level were similar to healthy control (p=0.376, p=0.379; respectively). In the follow-up of patients using ISO, a significant decrease was observed especially in SII levels (p=0.037). Although the lymphocyte count was not significantly different from the control group before treatment, it increased significantly after ISO and was significantly higher than both the control and pretreatment period (p=0.134, P=0.026, p=0.017; respectively). Although NLR was not different from control in the pre- and post-treatment period, the change in neutrophil and lymphocyte counts after treatment caused a statistically significant decrease in NLR (p=0.682, p=0.289, p=0.043; respectively). Conclusions: We believe that SII is a more useful parameter as an indicator of the anti-inflammatory effect of isotretinoin.