ANTIPHOSPHOLIPID ANTIBODIES ASSOCIATED VASCULAR EVENTS ARE AN UNDERRECOGNIZED CAUSE OF MORBIDITY AND MORTALITY AFTER LIVER TRANSPLANTATION: BENEFIT OF PLASMAPHERESIS AND ANTICOAGULATION IN TRANSPLANTED PATIENTS WITH HIGH THROMBOTIC RISK

Introduction and Objectives

Circulating antiphospholipid antibodies (aPL-abs) are common in end-stage liver disease and increase the risk of vascular thrombosis, graft loss, and morbidity post-liver transplantation (OLT). This risk is heightened in patients with prior thrombotic events or high aPL-ab titers. Plasmapheresis and anticoagulation have been proposed to treat aPL-induced complications.

To assess the preemptive effect of pre-OLT plasmapheresis combined with post-OLT anticoagulation in high-risk patients with aPL-ab undergoing OLT.

Materials and Methods

From 2005–2021, 321 patients undergoing OLT were screened for aPL-ab and lupus anticoagulant. Eighty-six patients (27%) tested positive; 29 met high-risk criteria and were randomized:

Group A (n=12): standard post-OLT prophylaxis (aspirin ± low-molecular-weight heparin).

Group B (n=17): pre-OLT plasmapheresis (1–2 hours prior) with fresh frozen plasma, followed by anticoagulation (low molecular-weight heparin or warfarin) for 6 months post-OLT.

Both groups had comparable liver disease etiology, severity, and immunosuppress-OLTsion regimens (steroids + cyclosporine/tacrolimus ± mycophenolate, basiliximab induction in 14 cases). Clinical, biochemical and Doppler evaluations were performed pre-OLT and during the first six months post-transplant. aPL-abs were measured at baseline, day 5 and day 30 post-OLT.

Results

In Group A, 11/12 patients developed post-OLT aPL-related complications (e.g., cerebrovascular ischemia, CAPS, hepatic/portal thrombosis), leading to 5 deaths, 1 graft loss, and 1 irreversible neurological injury. Median time to event: 3.6 ± 2.9 months.

In Group B, 3/17 patients developed complications (2 CAPS, 1 hepatic artery thrombosis) resulting in 2 deaths. Mean time to event: 10 ± 4 days.

Thrombotic complication rate: 37.9% (Group A) vs. 10.3% (Group B), p<0.0001. A non-significant trend towards higher aPL-related mortality was noted in Group A (17.2% vs. 6.9%, p=.06).

Conclusions

aPL-abs are a significant and often overlooked cause of post-OLT thrombotic complications and mortality. Pre-OLT plasmapheresis combined with early anticoagulation may reduce complications in high-risk patients.

Conflict of interest: None