A surgical case of long-term hemodialysis patient with the infected renal-arterial pseudoaneurysma

We report a hemodialysis patient presenting with fever of unknown origin (FUO) that was eventually diagnosed as infected pseudoaneurysm of the renal artery and successfully treated by surgery. A 47-year-old Japanese man who had been undergoing hemodialysis for twenty years was referred to our hospital with a twomonth history of fever and left flank pain. Computed tomography demonstrated an aneurysm measuring 2cm in diameter at the proximal left renal artery. Treatment with intravenous infusion of broad-spectrum antibiotics, including fungal coverage, failed to definitively eradicate the infection. We judged that infected aneurysm of the renal artery was the cause of FUO and flank pain, although the repetitive blood cultures were negative. Accordingly, the aneurysm and left kidney were resected simultaneously to avoid rupture of the infected aneurysm. Histological examination showed inflammatory change around the aneurysm of the renal artery and atypical cysts with papillary cell carcinoma in the left kidney. As the mechanism of infection to the renal artery in this patient, two pathways were considered. The first was the infection secondary into a pre-existing pseudoaneurysm complicated by blunt trauma. The second was due to necrosis of the tunica intima as a result of septic invasion of the vasa vasorum. infected aneurysm should be considered to be a case of FUO in patients undergoing hemodialysis.