Surgical treatment of recurrent abdominal aortic aneurysm in a patient with systemic lupus erythematosus☆☆☆

Case report 

The patient was a 26-year-old woman. The diagnosis of SLE was made when she aged 11 years on the basis of the following clinical and laboratory findings: diffuse malar erythematous skin eruptions, lymphadenopathy, pyrexia, leukopenia, anemia, arthritis, pericarditis, proteinuria, diffuse proliferative glomerulonephritis, positive serum antinuclear antibody, and lupus erythematous cell reactions. She was given varying doses of prednisolone with or without azathioprine since then. In November 1995, she had subjective awareness of a pulsatile abdominal mass for the first time. Computed tomography (CT) revealed an infrarenal AAA that was 4 cm in diameter (Fig. 1, A ).

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Fig. 1. A, First CT revealed infrarenal AAA that was 4 cm in diameter. B, Next CT 3 months after the first one revealed that the aneurysm grew to 8 cm in diameter with an irregular shape. C, The size of the residual abdominal aorta was within normal limits a year after the first operation. D, Five months after the last one, CT revealed a recurrent aneurysm with atheroma on the right side in the vicinity of the proximal anastomosis. It was 4.5 cm in diameter and irregular in shape.

The patient was a small woman with a height of 137 cm and a body weight of 32.5 kg. She was asymptomatic on admission. C-reactive protein was normal, and a blood culture was negative for bacteria and fungus. Angiography showed the AAA to be located near the proximal anastomotic site involving the left renal artery and barely avoiding the right renal artery (Fig 2, A ).

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Fig. 2. A, Angiography showed the AAA to be located near the proximal anastomosis involving the left renal artery and barely sparing the right renal artery. B, Postoperative angiography revealed good patency of the renal arteries.

In September 1997, an operation for the recurrent AAA was performed. Through a transperitoneal approach the suprarenal aorta, both renal arteries, and the proximal end of the previously implanted graft were clamped, the aneurysm was opened, and a layer of atheroma was resected. We confirmed that the orifices of both renal arteries were not stenotic. Then for the purpose of renal protection, the left renal artery was immediately connected to the patient's left radial artery. An 8-French balloon catheter was placed inside the left renal artery, and a 20-gauge detaining needle was used for the left radial arterial line that was in place from the preoperative period. The aorta was then transected between the right and left renal arteries. A proximal anastomosis between the aorta and an 18-mm Hemashield woven Dacron graft (Meadox Medicals, Boston, Mass) was performed. Right renal flow was restored after 20 minutes of ischemia. Left renal artery reconstruction was performed by the button technique, and the button was made to include as small a portion of the diseased aortic wall as possible. Selective left renal perfusion time was 43 minutes. Finally, anastomosis between the new and the previous grafts was performed. Postoperative renal function was satisfactory. Angiography (Fig 2, B ) and CT scan revealed good operative results.

Histopathologic findings were different from those of a common AAA. Severe chronic aortitis was thought to be present because of medial hypertrophy, vascularization, hyalinization, disappearance of smooth muscle cells, and the infiltration by many lymphocytes (Fig 3).

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Fig. 3. A, The wall of the AAA showed irregular thickening with intimal fibrin thrombus and medial inflammatory cell infiltrate (arrowheads ) accompanied by vascularization. Hematoxylin-eosin stain. Scale bar, 1 mm. B, Higher magnification of the media seen in A. Small vessels are irregularly running among smooth muscle cells, and focal hyalinization and elastic fiber splitting are also seen. Lymphocytes have infiltrated the perivascular space and are scattered among smooth muscles. Hematoxylin-eosin stain. Scale bar, 100 μm.

Discussion 

There are few available reports on true AAAs in patients with SLE, and articles on such aneurysms occurring because of severe inflammation are extremely rare. It is not well understood whether the cause of AAA with severe inflammation is attributable solely to SLE or whether a contribution of another autoimmune disease (eg, Takayasu's disease) is also there. When aneurysm formation was first noticed in this case, the patient's nephrosis was gradually deteriorating. However, during the assessment of other clinical findings, an acute flare-up of her SLE could not be confirmed, and a flare-up was not found at the time of recurrence either. This, together with the extreme rarity of reports of inflammatory AAA in SLE, makes it difficult to say that SLE alone is the cause of AAA in this case. Takayasu's disease is well known for aortitis in young women, and its histopathologic features are intimal fibrosis, medial scarring, and patchy chronic inflammatory infiltrate.1 Although obstruction or stenosis of the branch vessels was not observed, histopathologic findings of the present case were otherwise similar to those of Takayasu's arteritis. Although aneurysm formation in the infrarenal aorta in Takayasu's arteritis is also rare, Robbs et al2 reported a group of 18 patients who underwent an operation for infrarenal aortoiliac aneurysm due to Takayasu's arteritis. Igarashi et al3 described a case of Takayasu's arteritis associated with SLE showing irregular alternating dilatation and narrowing of the abdominal aorta. Takayasu's arteritis and SLE are usually found in Orientals.4, 5 We think that the aneurysms in this patient might have been caused by a combination of Takayasu's arteritis and SLE because the two entities appeared to have overlapped here. As for the recurrence, we preoperatively suspected a pseudoaneurysm due to anastomotic leakage or aortic crossclamping injury during the first operation. However, this was excluded during reoperation. Also, the cause of recurrence was the continuing severe aortitis as found on histopathologic examination.

The Table shows previous reports on true AAAs in patients with SLE who were surgically treated. To the best of our knowledge, there are only two previous reports6, 7 of AAA with severe inflammation in SLE. Histopathologic findings of those two cases showed a prominent inflammatory infiltrate in the aortic wall similar to that of our present case. These three patients with severe inflammation were relatively younger than the others8, 9, 10 in the Table whose diseases were caused by atherosclerosis due to prolonged steroid therapy and not by severe inflammation.

Table.

	Author/period	Age/sex	Duration of steroid therapy	Shape or growth of AAA	Histopathology	Postoperative course
	Stehbens6/1993	56/M	16 y	Irregular, lobulated	Severe inflammation	Uneventful
	Shibata7/1994	30/F	17 y	Rapid growth	Severe inflammation	Died of bleeding
	Present case/2000	24/F	13 y	Irregular, rapid growth	Severe inflammation	Recurrence
	Sato9/1995	52/F	16 y	Fusiform	Atherosclerosis	Died of aortic dissection
	Marubayashi8/1998	45/F	18 y	Dumbbell shaped	Atherosclerosis	Uneventful
	Nosaka10/1999	47/F	17 y	Fusiform (rupture)	Atherosclerosis	Uneventful

In accordance with the data presented in the Table, we suppose that AAAs in patients with SLE are classifiable into two types: AAAs that are mainly caused by inflammation and those that are mainly caused by atherosclerosis due to prolonged steroid therapy. Prolonged steroid therapy can increase the severity of atherosclerosis,11 and the latter, in turn, can initiate and accelerate the process of aneurysm formation.

With regard to renal artery reconstruction, we chose reimplantation, not bypass grafting, because orifices of renal arteries were not stenotic. We thought that selective renal perfusion flow from the radial arterial line might be able to provide the minimum protection to the kidney for a little more than 30 minutes. Moreover, this method is easy and free from the hazards of reperfusion injury. More investigations are necessary to find safer and more convenient ways of AAA surgery with renal artery reconstruction.

In conclusion, we surgically treated a recurrent AAA involving the left renal artery that was found after a previous operation for infrarenal AAA in a patient with SLE. Etiology of the AAA might be a combination of Takayasu's arteritis and SLE because the two entities appeared to have overlapped.