Antiphospholipid antibodies and hyperhomocysteinaemia in patients with vascular occlusive disease.

Hyperhomocysteinemia (HHcy), lupus anticoagulant (LA) and anticardiolipin antibodies (ACA) are independent risk factors for thrombosis. Even though risks are cumulative, the clinical impact of the association is unknown. Preliminary data suggested that HHcy might be associated with transient LA and ACA, disappearing after lowering HHcy.

Endogenous or exogenous coagulation factor level and the response to activated protein C.

Background: The abnormal response to activated protein C could be the mechanism to explain the prothrombotic role of elevated coagulation factor levels.

Objective: We evaluated the effect of factor VIII, II, or X (FVIII, FII, or FX) levels on activated protein C resistance technique and its association with the resistant phenotype.

Materials And Methods: The correlation between APCR and FVIII was assessed in 36 samples, after Desmopressin infusion and the correlation between FII or FX and APCR in 15 patients with plasma levels between 100-125 U/dl.

Mechanical heart valve prostheses and persistent lupus anticoagulant: is the thrombotic risk increased?

The risk of thrombosis in patients with mechanical heart valve prostheses in spite of life-long adequate anticoagulation is 1-2% per year. Current recommendations for anticoagulation take into account the prosthesis itself and the co-morbid conditions that enhance the thrombotic risk. Lupus anticoagulant is diagnosed in many thrombotic recurrences.

Morbidity of lupus anticoagulants in children: a single institution experience.

Introduction: The lupus anticoagulant (LA) and the anticardiolipin antibodies (ACA) are the antiphospholipid antibodies more relevant clinically. Their clinical manifestations are diverse with most patients being asymptomatic while others present venous or arterial thrombosis, and more rarely, bleeding. Our objectives were to evaluate clinical presentation of LA in children and to correlate it to LA behavior.

Anticoagulation in the antiphospholipid syndrome.

Our objectives were to evaluate thrombotic complications in patients with lupus anticoagulant fulfilling Sapporo criteria, anticoagulated with an intended INR 2.0-3.0 due to venous and arterial thrombosis.

Antibodies directed to protein S in patients with systemic lupus erythematosus: prevalence and clinical significance.

Antibodies directed against protein S (anti-ProtS) may be involved in the development of thrombosis in patients with the antiphospholipid syndrome. We assessed the prevalence and clinical significance of anti-ProtS and evaluated their immunological characteristics in 184 patients with SLE and 99 healthy donors. All patients were tested for IgG anti-ProtS by an in-house ELISA.

Antiphospholipid antibodies impact the protein C (PC) pathway behavior.

Antiphospholipid antibodies may interfere with the PC pathway, displaying a resistance to the activated PC (resistant phenotype). This effect was evaluated by the APCR and the ProCG systems in 36 lupus anticoagulant samples, yielding abnormal results in 47% of APCR(original), 17% of APCR(modified), and 22% of ProCG test. ProCG values correlated with APCR(original) but not with APCR(modified).

A chromogenic substrate method for detecting and titrating anti-factor VIII antibodies in the presence of lupus anticoagulant.

Background And Objectives: The development of neutralizing anti-factor VIII antibodies (a-fVIII) is a major clinical complication. Lupus anticoagulant (LA) might affect detection of a-fVIII, since both inhibitors may act on the same coagulation pathway. Our aim was to accomplish unequivocal detection and titration of a-fVIII even in the presence of LA.