Factor V Leiden mutation in Sneddon syndrome

Sneddon syndrome (SNS) is characterizedby the associationof ischaemic cerebrovascularevents and widespread livedo racemosa. Its pathophysiology is still controversial. The aim of this study was to evaluate the prevalence of factor V Leiden mutation in consecutive patients referred for SNS according to antiphospholipid antibodies (aPL) status. Fifty-three Caucasian patients were enrolled from 1996 to 2001. Diagnosis of SNS was based on the presence of a widespread livedo racemosa and at least one clinical neurologic ischaemic event. The following investigations were performed: detection of antithrombin III, protein C and protein S deficiency, lupus anticoagulant, anticardiolipin and anti-b2 glycoprotein I antibodies, biologic false-positive test for syphilis, and factor V Leiden mutation by direct genomic analysis. Fisher’s test and t-test were used for statistics. Detection of aPL on multiple determinationswas negativein 31 patients (group 1) and positivein 22 patients (group 2). Factor V Leiden mutation was detected in six patients (11.3%), heterozygousin all. The frequency of this mutation was statistically higher in group 1 (6/31, 19.3%) than in group 2 (0/22; P 0.035). Within aPL-negative SNS, the comparison of patients with versus without factor V Leiden mutation showed no difference for clinical data or familial history of thrombosis. A high prevalence of heterozygous factor V mutation was found in aPL-negative patients with SNS. This finding adds further arguments to consider SNS as a heterogeneous entity.