Central retinal vein occlusion after liver transplantation

Abstract

Editor, Central retinal vein occlusion (CRVO) is associated with various systemic abnormalities (McGrath et al. 1978). In organ recipients, however, CRVO has been reported only after heart or heart–lung transplantation (Keller & Linn 1990; Allinson et al. 1993). To our knowledge, this is the first report of CRVO in liver transplant (LT) recipients. From 1995 to 2006, 3656 organ transplantations were performed at Asan Medical Centre (1290 liver, 786 bone marrow, 1445 kidney and 135 heart transplants). Of these patients, 1205 were examined by the Department of Ophthalmology. The medical records of these 1205 patients were reviewed retrospectively. CRVO was diagnosed in five patients, all LT recipients (Table 1). Interestingly, one patient developed sequential CRVO in both eyes following two LTs (1, 2). Fundus photographs of both eyes of patient 4 at first presentation. Features of venous tortuosity, macular thickening and intraretinal haemorrhage were observed in all four quadrants of the fundus of the right eye. There were no specific focal lesions, except small atrophic areas nasal to the macula, in the left eye. (A) Fundus photographs of the same patient at second presentation. There was a new onset of venous tortuosity, cotton-wool spots, retinal haemorrhages and macular oedema with ischaemia in the left eye. (B) Fundus photographs and Fluorescein angrogram (FA) of both eyes 6 months later. Severe ischaemia and non-perfusion were observed in the left eye. CRVO developed 3–40 months (mean 15 months) after LT. Haematological examination showed alterations in blood coagulability secondary to hepatic failure, normalization of absolute platelet count, INR and activated partial thromboplastin time. Increases in factor VIII and activated protein C were observed in the patient with bilateral CRVO (patient 4). A mild increase in factor VIII (195%, reference value 60–120%) was also observed in patient 5. Among the six affected eyes of these five patients, four developed non-perfused CRVO and two developed perfused CRVO, with one of the latter converted to non-perfused CRVO during follow-up. Despite aggressive treatment, including laser photocoagulation, vitrectomy and glaucoma surgery, final visual acuity equal to or worse than 20/200 occurred in three of the six eyes. CRVO has been found to be a complication of heart and lung transplantations (Keller & Linn 1990; Allinson et al. 1993), with cardiopulmonary bypass during heart–lung transplantation associated with factors predisposing to CRVO development. Pulmonary thromboembolism and/or intracardiac thrombus formation have been reported during LT or immediately after graft reperfusion (Gologorsky et al. 2001; Lerner et al. 2005). Among the factors inherent to LT that may be related to these major intraoperative complications are excessive activation of the coagulation system secondary to injury to a large capillary bed, venous stasis during clamping of the portal vein and inferior vena cava, activators released from the grafted liver and massive blood transfusion (Gologorsky et al. 2001). It is unclear, however, why CRVO only developed several months to years after transplantation and exclusively in LT recipients, although CRVO may have been caused by hypertension and/or hyperlipidaemia secondary to the large amount and duration of immunosuppressive therapy administered to LT recipients. Although the absolute levels of serum lipids, including cholesterol, before LT were within reference values in four of our five patients, these serum lipid levels increased markedly after LT. These patients had also received more combination treatments, including prophylaxis for opportunistic infections, and large quantities of transfused blood during the immediate postoperative period. This may be especially applicable to the patient with bilateral CRVO, who was also the only patient treated with interferon α-2b because of chronic hepatitis C. In addition, LT may induce hypercoagulability or relative hypercoagulability, especially because these patients had experienced decreases in platelets and coagulation factors caused by liver failure. The patient with bilateral CRVO was thrombophilic, as evidenced by elevated factor VIII and activated protein C. Factor VIII tested immediately after the onset of CRVO in patient 5 increased slightly. Although her fibrinogen (345 mg/dl) and antithrombin III (96%) levels at the onset of CRVO were within normal limits, they were very low before LT (104 mg/dl and 9%, respectively). CRVO could occur during follow-up in LT recipients. It may be the main cause of morbidity of patients who showed general recovery after successful LT, warranting familiarity with this complication. It is important to determine the risk factors for the development of CRVO in LT recipients, as well as possible preventative measures.