Massive mesenteric and portal venous thrombosis secondary to hormone replacement therapy

Introduction

Mesenteric ischaemia was first described in the 15th century by Beniviene and then further reported in the 19th century by Virchow. ¹ Arterial embolism is the commonest cause of mesenteric ischaemia (64%); venous thrombosis makes up only approximately 5% of cases. ² The clinical presentation can be variable but frank peritonitis is only present once transmural infarction or perforation is present. Early aggressive intervention is required to preserve viability of the affected bowel. However, if reperfusion is not an option then non-viable bowel needs to be removed. Following initial surgery, assessment of the viability of the remaining bowel is required. Re-look laparotomies remain the gold standard for this ³ and occasionally multiple resections are required. The authors present an unusual case of massive mesenteric ischaemia secondary to venous thrombosis caused by hormone replacement therapy (HRT) in a 44-year-old female. They highlight the fact that HRT can cause such catastrophic events and the importance of the re-look laparotomy and multiple bowel resections which can be lifesaving.

Case report

A 44-year-old female was admitted as an emergency with severe abdominal pain. This pain started nine days prior to admission and had been worsening. Medical history included tonsillectomy, hypertension and anaemia of unknown aetiology. Her medication history includes diazepam, propranolol, omeprazole, ferrous fumarate and Elleste Duet. Initial observations showed her to be apyrexial and hypotensive. On examination she was very tender in her epigastrium with some rebound tenderness and guarding. Blood tests showed her haemoglobin to be 7.1 g/dl, white cell count to be 12.1 × 10⁹/l and CRP 171 mg/l with the remainder of her blood tests being normal. Plain radiology was unremarkable.

Despite adequate resuscitation her condition deteriorated, and her pain worsened. An urgent CT scan showed thrombosis in her splenic, portal, and inferior mesenteric veins with thickened loops of jejunum – indicating possible ischemia (Figures 1 and 2). OPEN IN VIEWER

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Figure 2.

Transverse section of CT that demonstrates thrombosis in her splenic, portal, and inferior mesenteric veins with thickened loops of jejunum.

Emergency laparotomy was performed and 80 cm of ischaemic small bowel resected. The remaining small bowel was very oedematous and dusky with friable mesentery. Primary anastomosis could not be performed due to above findings. Both ends of bowel were not able to be brought to the surface due to her body habitus and so they were temporarily closed with a Foley’s catheter in the proximal end. Over the next eight days she had five planned re-look laparotomies and further multiple small bowel resections. At the time of her final laparotomy, she had her small bowel anastomosed together. She made a slow and steady recovery and despite thorough haematological investigation, no cause for her thrombosis was found. She had no other risk factors for venous thrombosis other than HRT. She was started on life-long warfarin therapy and eventually discharged home 78 days after admission. She remains well at 18 months’ follow-up.

Discussion

HRT has long been given to women in order to help with menopausal symptoms. HRT tends to come in two forms: combined HRT (containing oestrogen and progestin) or oestrogen only HRT. ⁴ Despite its side effects, HRT remains the most effective method of controlling vasomotor menopausal symptoms in the short term. ⁴

The risk of venous thromboembolism (VTE) has increased since the introduction of HRT^5–7 and is highest during the first year after starting HRT. It is believed that hormone-based medications mediate this effect by causing an increase in the markers of activated coagulation, a decrease in coagulation inhibitors and cause activated protein C resistance. ⁸

The oral contraceptive pill has also been shown to have an increased risk of VTE. However, the absolute risk remains higher in users of HRT, probably due to the fact that these users tend to be older in age. The risk of VTE is further increased by the presence of other risk factors including previous VTE, thrombophilia, presence of cancer, obesity and immobilisation. ⁵

As we have demonstrated, in patients with mesenteric ischaemia, multiple laparotomies and bowel resections may be required before restoring intestinal continuity. Re-look laparotomy as a concept was first introduced by Shaw in 1965 ⁹ and used to assess the adequacy of initial resection in bowel ischaemia. A planned re-look at 24–48 h will not only allow the surgeon to assess the viability of remaining bowel but also allows body physiology to stabilise and supportive measures to be instigated.^3,9 In a recent study by Kaminsky et al. ¹⁰ only 20% of those undergoing re-look laparotomy survived compared with 65% who did not. This difference in survival can be explained by the fact that those who required more than one laparotomy had more significant disease and required multiple resections of bowel. They were also by definition more unwell and in these patients, performing a re-look laparotomy almost certainly doubles the risks of anaesthesia, and infection related complications. ³ However, our case demonstrates that in the correct patients, aggressive surgical intervention including multiple laparotomies and bowel resections can be lifesaving.

Conclusions

We conclude that venous thrombosis can be a devastating condition affecting any venous system. It is important to consider this diagnosis in unusual presentations. We demonstrate that aggressive surgical management and re-look laparotomies can be lifesaving in severe mesenteric ischaemia.