Abstract
1. A circulating anticoagulant was demonstrated in three patients with "collagen disease." In all cases it was associated with a false positive blood serology and a four plus cephalin cholesterol flocculation.
2. In one instance, the anticoagulant was transferred to a newborn infant where it persisted for seven weeks. The infant also demonstrated the abnormal serologic and turbidimetric tests during the first six months of life.
3. The anticoagulant probably acted as anti-thromboplastin.
4. The occurrence of a clotting inhibitor in association with other manifestations of hypersensitivity and its transplacental transfer strongly suggest that the mechanism of development is immunologic in type.
5. This study included a total of thirty patients with lupus erythematosus disseminatus and associated conditions conventionally grouped under the term "collagen disease." The incidence of circulating anticoagulants was 10 per cent.
