Abstract
BACKGROUND: The management of thromboangiitis obliterans (TAO) remains a medical challenge because of its unknown etiology. It is also not known whether it is a systemic or localized disease or a type of autoimmune vasculitis. METHODS: In this study, we evaluated the serum level of IL-17 and IL-23 which increase in both systemic inflammation and autoimmunity, in 60 TAO patients and 30 age- and smoking habit-matched controls. Also, IL-22, which has reported high level during infection but not in autoimmunity, was evaluated. RESULTS: The serum levels of IL-17, IL-22 and IL-23 were significantly higher in the TAO patients in comparison with the controls (P<0.001). Notably, the serum levels of IL-17, IL-22 and IL-23 were highest in the patients with the chief complaint of chronic ulcer and lowest in the patients with gangrene (P<0.05). Also, the serum level of IL-22 was significantly higher in the anemic patients in comparison with the non-anemic patients (P=0.03). CONCLUSION: Owing to our findings, TAO appears more likely to be a systemic disorder rather than a localized vasculopathy. Therefore, treatment protocols based on systemic treatment of TAO patients may be more helpful than localized treatment, such as bypass surgery and endovascular procedures. Also, according to our findings regarding the high level of IL-22, the trigger of TAO development may be an infectious pathogen. However, additional research is highly recommended to investigate whether TAO is an infectious disease or an infectious-induced autoimmunity.