Obstructive uropathy due to inflammatory abdominal aortic aneurysm occurring 18 years after surgical repair of an atherosclerotic aneurysm

Sir, Chronic periaortitis has a wide range of causes [1]. Obstructive uropathy associated with chronic periaortitis complicating abdominal aortic aneurysm (AAA) repair is well recognized and tends to occur early within 12 months of AAA repair. It is unusual for this to occur many years after surgery. A 71-year-old male was referred to the renal team after an emergency hospital admission by the medical team with acute kidney injury. Serum creatinine was 774 µmol/L (eGFR 7 mL/min/L), having been 140 µmol/L (eGFR 47 mL/min/L) 4 months previously. There was history of an atherosclerotic AAA open repair with an aortic graft in 1990. In 1994, the patient had a surgical exploration and evacuation for retroperitoneal haematoma. In 1995, the patient underwent surgical repair for leaking AAA. The proximal half of the graft was resected and replaced with a second Gelsoft graft (rifampicin soaked). In September 2008, the patient was admitted to our hospital with malaise, anorexia and oliguria. On examination, there was a pulsatile abdominal mass just lateral (left) to his midline laparotomy scar. An abdominal CT scan showed a large infrarenal AAA measuring 9.2 cm. The right kidney was of normal size but severely hydronephrotic with a hydroureter extending down to the level of the aortic bifurcation. The left kidney was small and also hydronephrotic (Figure 1). There was extensive fibrosis noted at the level of the aortic bifurcation associated with obstructive uropathy (Figure 2). Fig. 1 Bilateral hydronephrotic kidneys. Fig. 2 A large infrarenal abdominal aortic aneurysm with extensive fibrosis. The patient remained hypotensive with a poor urine output. He subsequently deteriorated and died 4 days after admission. Early hydronephrosis developing within the first year occurs in 10–20% of patients following surgical graft repair of AAA. The most probable cause for this is mechanical due to the compression of the ureter against the native iliac artery from the anteriorly placed graft [2]. In a prospective study of 101 patients who underwent aortofemoral and aortoiliac reconstructive surgery, 12% of patients developed mild to moderate hydronephrosis. All patients were asymptomatic, and the obstruction resolved spontaneously in 10 of 11 patients within 3 months of onset. The incidence of delayed hydronephrosis occurring 1 year or more post surgical repair is unknown. This complication may be relatively common after reconstructive vascular surgery as in our patient, especially in association with infected grafts [3]. The mechanism for the development is not fully understood. The most widely held view is that this complication develops secondary to an inflammatory process causing fibrosis [4]. The long time interval is unusual and suggests perhaps a different mode of inflammatory pathways compared to what is commonly seen in early obstructive uropathy associated with surgical graft repair of AAA. More research is needed to elucidate the mechanisms underlying chronic periaortitis [5]. Conflict of interest statement. None declared.