Long-term persistence of anti-β2 glycoprotein I in treated leprosy patients

β2 glycoprotein I (β2GPI) is a phospholipid binding protein that plays an important role in endothelial stability, blood coagulation, clearance of apoptotic debris and other physiologic processes. Anti-β2GPI antibodies occur in normal individuals and transiently during the course of infections, but are also associated with thrombotic events in autoimmune disease: the antiphospholipid syndrome (APS). A total of 31 out of 37 treated leprosy patients previously found to present high titers of IgM anti-β2GPI and/or anticardiolipin antibodies (aCL) remained positive for IgM antiphospholipid antibodies (aPL), and exhibited high titers of anti-β2GPI. The 37 patients were part of the 77 aPL-positive patients from a previous study that evaluated 158 leprosy patients. The median time elapsed between the first and second sample was 66 months. None of the 37 patients had any thrombotic event and 24 had a reactional state and were still requiring the use of prednisone, thalidomide or both. None of them fulfilled World Health Organization criteria for leprosy recurrence.