Investigation of the anti-inflammatory effect of isotretinoin in patients with acne vulgaris, A new indicator: Aggregate Index of Systemic Inflammation

Objective: Acne vulgaris is a chronic inflammatory skin disease, and isotretinoin. The vitamin A derivative, is widely used in its treatment. The effects of isotretinoin on 
systemic inflammation remain controversial. Neutrophil-lymphocyte ratio (NLR), systemic inflammatory response index (SIRI), systemic immune-inflammatory index 
(SII), and total index of systemic inflammation (AISI) are inexpensive and easily calculated biomarkers derived from complete blood counts. These markers are used to 
assess the presence of inflammation in systemic and dermatological inflammatory diseases. This study aimed to evaluate changes in these markers during isotretinoin 
therapy in acne vulgaris.
Materials and Methods: The study included 183 patients receiving isotretinoin. Complete blood counts were retrospectively recorded at 0, 3, and 6 months, and NLR, 
SII, SIRI, and AISI values were analyzed.
Results: The absolute neutrophil count decreased at 6 months compared to baseline (p=0.032), and the lymphocyte count increased at 3 and 6 months (p=0.003 
and p=0.043, respectively). The platelet count increased at the end of the 3rd month and decreased at the end of the 6th month compared to baseline (p=0.002, 
p=0.012, respectively). NLR, SIRI, SII, and AISI values have continued to decrease during treatment, and a significant decrease has observed at the end of the 6th month 
(p=0.001, p=0.006, p=0.016, p=0.029, respectively). 
Conclusion: Systemic isotretinoin therapy in patients with acne vulgaris is associated with significant reductions in NLR, SIRI, SII, and AISI. These findings support the 
presence of a systemic anti-inflammatory effect of isotretinoin and contribute to the ongoing debate regarding its impact on systemic inflammation.