Antiphospholipid antibodies in renal allograft recipients.

Background: Antiphospholipid antibodies (APLAs) are associated with an increased risk of thrombosis. The role of APLAs as a marker of thrombosis in renal recipients has not been established. We sought to determine the prevalence of APLAs in renal recipients and investigate their association with thrombosis.

Material: The study included 37 renal recipients: 17 women and 20 men of ages 22-69 years. The 2 subgroups were one of patients without (n = 27; T-) and a second, with a history of severe thrombosis (n = 10; T+) subgroups, We determined lupus anticoagulant (coagulation methods) and anticardiolipin antibodies (ACL), anti-Beta2GlicoproteinI antibodies (anti-B2GPI), antiprothrombin antibodies (anti-PT) in immunoglobulin (Ig)G and IgM isotype using enzyme-linked immunosorbent assay. The determinations were made twice at a 6-months interval. The mean duration of follow-up was 12 months.

Results: The most commonly detected antibodies were anti-β2GPI IgM (16.22%) and aCL IgG (13.8%). No differences were identified when the prevalence APLA was compared between T- and T+. A significant correlation was found between anti-β2GPI IgM and aCL IgM (P = .0328); anti-β2GPI IgM and aCL IgG (P = .0198) and aCL IgM and aCL IgG (P = .0252). No differences in serum creatinine were observed between the T- and T+ cohorts. During the follow-up, 2 female patients in the T+ produced APLAs and were treated with low-molecular-weight heparin. During follow-up one patient developed thrombosis (TMA), which led to graft loss. The other patient with normal renal graft function did not experience a recurrence of thrombosis.

Conclusions: The prevalence of APLAs in renal transplant recipients was higher than in the general population. The study did not demonstrate any predictive value of APLAs as markers of thrombosis in renal recipients. Routine determination of APLAs is not necessary in all transplant recipients.