Aortic infections are rare, life-threatening and constitute a major challenge in surgical management. This thesis aims to evaluate short – and long-term outcome of endovascular aortic repair (EVAR) for mycotic aortic aneurysms (MAA) and the subsequent risk of recurrent infections, changes in surgical practice over time for abdominal MAAs in Sweden and outcome for different treatment modalities, as well as the risk of secondary vascular infection after treatment with Open abdomen after aortic surgery. Paper I, a retrospective single centre study of patients with MAA treated with EVAR, demonstrated a good short-term outcome, 91% survival at 30-days, and acceptable mid-term survival, 73% at 1-year. Paper II, a retrospective international multicentre study of patients treated with EVAR for MAA, confirmed the results in paper I, and showed that EVAR is feasible and for most MAA patients a durable treatment option, 5-year survival was 55% and 10-year 41%. A total of 19% died from an infection-related complication, mostly during the first postoperative year. Non-Salmonella-positive culture was a predictor for late infection–related death. Paper III, a population-based cohort study on all abdominal MAAs operated on between 1994-2014 in Sweden. Overall survival was 86% at 3-months, 79% at 1-year and 59% at 5-years. The survival was significantly better after endovascular compared to open repair up to 1-year without increasing recurrence of infection or reoperation, thereafter there was no difference. After 2001 EVAR constituted 60 % of all repairs, thus indicating a paradigm shift in treatment for abdominal MAAs in Sweden. Paper IV, a prospective multicentre study of patients treated with open abdomen after aortic surgery. Infectious complications, such as graft infections, occurred after intestinal ischaemia and prolonged OA-treatment, and were often fatal.