Case report

Br. J. Surg. 1990, Vol. 77, February, 228-229

Pregnancy in a renal transplant recipient complicated by rupture of a transplant renal artery an eu rysm

A. J. Richardson, M. Liddington, A. Jaskowski*, J. A. Murie, M. Gillmer* and P. J. Morris

Nuffield Departments of Surgery and *Obstetrics, University of Oxford, John Radcliffe Hospital, Oxford, UK Correspondence to: Mr J. Murie, Department of Surgery, The Royal infirmary, Edinburgh EH3 9YW, UK

Although death in a renal transplant recipient is often due to uncontrollable factors, this is not always true. This report deals with a life-threatening condition for which effective treatment is available if the diagnosis is made sufficiently early. The rarity of transplant renal artery aneurysm rupture should not dissuade us from advising ultrasound examination of the graft and vessels at the time of routine obstetric ultrasound examination in pregnant transplant recipients.

Case report The patient became pregnant for the first time at the age of 20 years. Progress was satisfactory with no abnormality on routine ultra- sonography until 32 weeks when she was admitted to the obstetric unit because of postcoital back and suprapubic pain. Physical examination was unremarkable. Cardiotocography, fetal breathing tests and ultrasonography were normal. Blood pressure was 130/90 mmHg and serum creatinine was 90pmol/l without abnormal protein in the urine. After 6 days observation she was allowed home, only to be readmitted 2 weeks later because of a 2.5 kg weight gain and mild proteinuria. Her blood pressure was 130/80mmHg. Fetal blood flow by Doppler ultrasonography and fetal heart sounds were normal. Serum creatinine was 85pmol/l. A putative mild toxaemia of pregnancy was treated by bed rest; 3 days after admission she became suddenly hypotensive and collapsed.

At emergency caesarian section a large amount of blood was evacuated from the peritoneal cavity and a dead infant was delivered. As extensive bleeding seemed to come from the region of the transplanted kidney, the aorta was temporarily compressed which allowed reasonable control of the haemorrhage while vascular surgical assistance was obtained. A ruptured aneurysm of a pelvic artery was recognized and further dissection revealed that this arose either from the internal iliac or renal artery near the site of the anastomosis between these two vessels or from the anastomosis itself. It was not possible to identify which. The aneurysm sac was mobilized and the artery clamped proximally and distally. After excision of the aneurysm, an end-to-end anastomosis was performed between the residual internal iliac and graft renal arteries and the site was marked with a Ligaclip (Ethicon Ltd., Edinburgh, UK). The patient returned home 9 days later. A marginal rise in serum creatinine did not exceed the upper limit of the normal range. Angiography was performed 3 months after surgery to exclude other arterial abnormalities of the transplant renal artery. None was found (Figure I ) . Eight months after operation the patient remains well with a serum creatinine of 90pmol/l.

Discussion Rupture of a mycotic aneurysm of a transplant renal artery is well recognized'.' but non-mycotic aneurysms are rare3-'. In this patient the aneurysm may have arisen in the graft renal artery, in the native internal iliac artery or from the anastomosis

Figure 1 is marked with a Ligaclip

Angiogram 3 months after surgery: site of aneurysm repair

itself. Over 50 per cent of ruptured aneurysms in women under the age of 40 years are related to pregnancy, the most common sites being the cerebral circulation, abdominal aorta and splenic artery6. Eighteen cases of native renal artery aneurysm rupture during pregnancy have been reported in the English language literature and 94 percent occurred in the third trimester with an overall mortality of 56 per cent for the mother and 82 per cent for the fetus'. Between 1967 and 1982 there were 24 maternal deaths in England and Wales due to rupture of intra-abdominal visceral arterial aneurysms' (ten splenic artery, ten abdominal aortic, three renal artery and one hepatic artery aneurysm). Most ruptures occurred in the last weeks of pregnancy.

The mechanism of aneurysm development and rupture is unclear. Experimental evidence suggests that oestrogen may cause intimal hyperplasia and alteration and collagen deposition, predisposing to aneurysm f o r m a t i ~ n ~ ~ ' ~ , and increases in circulating blood volume and regional blood flow may predispose to arterial dilatation6. Pregnancy may cause intimal hyperplasia and medial structural alteration which is histologically similar to that associated with hypertension lo-' '. The renal artery in the pregnant rat undergoes changes in vessel structure which may become more marked after the third p r e g n a n ~ y ' ~ . This change is similar to that of fibromuscular dysplasia, which may lead to renal artery stenosis and post-stenotic aneurysmI4. Only two of the 18 pregnancy-related ruptures of native renal artery aneurysms have been related to this condition' and in the present case there was no evidence of renal artery stenosis.

228 ~7-1323/90/02022842$3.00 0 1990 Butterworth & Co (Publishers) Ltd

Case report

We report what we believe to be the first case of a transplant renal artery aneurysm rupture occurring in pregnancy. This diagnosis should be considered in any pregnant renal transplant recipient who develops circulatory collapse with abdominal pain. More extensive pelvic ultrasonography in such pregnant patients may be indicated.

References 1.

2.

3.

4.

5.

6.

Benoit G , Icard P, Le Baleur A et al. Mycotic aneurysm and renal transplantation. Urology 1988; 31 : 63-5. Squiflet JP, Pirson YD, Dardenne AN et al. Mycotic aneurysm ofrenal graft artery: diagnosis by ultrasonography. Urology 1983; 22: 2 1 2 4 . Goldman MM, Tihey NL, Vineyard GL et al. A twenty-year survey of arterial complications of renal transplantation. Surg Gynecol Obstet 1975; 141: 75860. Renigers SA, Spigos DG. Pseudoaneurysms of the arterial anastomosis in a renal transplant. AJR 1978; 131: 5 2 5 4 . Mulderije ED, Berden JM, Buskens FG et a/ . False and true aneurysms of the renal artery after kidney transplantation: a report of two cases. Br J Radio1 1985; 58: 896-9. Barrett JM, Van Hooydank JE, Boehm FM. Pregnancy-related

7.

8.

9.

10.

1 1 .

12.

13.

14.

rupture of arterial aneurysms. Obstet Gynecol Surg 1982; 37: 55746. Cohen JR, Shamesh FS. Ruptured renal artery aneurysms during pregnancy. J Vasc Surg 1987; 6 : 51-9. Department of Health and Social Security. Report on Confidential Enquiries into Maternal Deaths in England and Wales. Triennial publication. London: HMSO. Gamma1 EB. Intimal thickening in arteries of rats treated with synthetic sex steroids. Br J Exp Pathol 1976; 67: 248-54. Irey NS, Norris HT. Intimal vascular lesions associated with female reproductive steroids. Arch Pathol 1973; %: 227-34. Menallo-Estrella P, Barker AE. Histopathologic findings in human aortic media associated with pregnancy. Arch Pathol 1967; 83: 336-41. Schwarz 0, Hawker WD. Hyperplasia and hypertension of the uterine vessels during various stages of pregnancy. Am J Obstet Gynecol 1950; 60: 967-71. Wexler BC. Spontaneous arteriosclerosis of the mesenteric, renal and peripheral arteries of repeatedly bred rats. Circ Res 1964;

Wylie EJ, Perloff D, Wellington JS. Fibromuscular hyperplasia of the renal arteries. Ann Surg 1962; 156: 592-609.

15: 485-96.

Paper accepted 27 July 1989

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