P LEUNG1, A TOSOLINI1, A HEDLEY1
1Austin Health, Victoria
Kidney transplant recipients experience an increased risk of venous thromboembolism (VTE), the aetiology of which is multifactorial, including improved uraemic platelet dysfunction, immunosuppression medications, rejection episodes and later complications including malignancy and weight gain. This study aims to determine the incidence of and ascertain the risk factors for VTE following kidney transplantation. A single-centre, retrospective observational study was conducted, examining 132 kidney transplant procedures performed between 1 January 2012 and 31 December 2016 on adult recipients (37.9% female, median age at transplantation 55 years). All patients received standard peri-operative care and immunosuppression. The incidence of deep vein thromboses (DVT) was 6.1% and pulmonary emboli (PE) was 5.3%. All DVTs and 71.4% of PEs occurred within six months of transplantation. A provoking event was identified in 85.7% of patients with PEs including subsequent prolonged hospital admission, post-transplant lymphoproliferative disorder, treatment of rejection with methylprednisolone, plasma exchange and intravenous immunoglobulin, immobility and plasma exchange for donor-specific antibodies. Surgical factors, including side of graft (p=0.540), lymphocele formation (p=0.917), cold ischaemic time (p=0.992), warm ischaemic time (p=0.324) and hospital length of stay (p=0.725) were not associated with an increased risk of VTE. Both haemoglobin (p=0.018) and haematocrit (p=0.046) one-year post transplant were lower in the VTE group. Seven patients died from causes not attributed to VTE. Conclusion: The first six months after kidney transplant appear to be a high-risk period for VTE. It may be appropriate to extend the duration of thromboprophylaxis beyond the immediate post-operative period depending on individual risk factors such as hospitalisation or treatment of rejection.
Dr Leung is a third year nephrology advanced trainee at Eastern Health, with interests in kidney transplantation and peritoneal dialysis.