We report a 10-year follow-up on 52 patients with raised levels of ant
icardiolipin antibodies (aCL) who were first seen at our tertiary refe
rral centre in 1986. The clinical and serological features of these 52
patients are described. Thirty-one patients had the antiphospholipid
syndrome (APS) in 1986. Nine of these patients (29%) had further throm
botic events during the follow-up period. Of the other 21 aCL positive
patients without clinical manifestations of APS, 11 (52%) developed t
he syndrome over this period. Five patients (10%) died during the foll
ow-up. Close monitoring of patients with connective tissue diseases an
d aCL is essential as the likelihood of developing antiphospholipid sy
ndrome is high.