Transient appearance of the lupus anticoagulant in three family members sharing the A11B35DR4 haplotype
Blood Coagulation Disorders
Blood Coagulation Factors
Genes, MHC Class II
A prolonged partial thromboplastin time in a patient was investigated, as well as those of his family members. One sibling, the mother, and the patient all shared a lupus-like anticoagulant and low Factor XII levels in association with the A 11, Bw 35, DR 4 haplotype previously found in familial lupus erythematosis. The rest of the family had normal coagulation profiles and the entire family had normal findings when tested for ANA, complement and immune complexes. After being confirmed in a second coagulation laboratory, the lupus-like anticoagulants in the three affected members of the family disappeared upon retesting 3-8 weeks later.