Absent factor II in systemic lupus erythematosus. Immunologic studies and response to corticosteroid therapy

This report describes a patient with active systemic lupus erythematosus (SLE) who evidenced severe bleeding consequent to a profound and isolated reduction in plasma factor II (prothrombin) activity. Absence of the factor is documented by immunologic means and its return after corticosteroid therapy is demonstrated. The authors recommend inclusion of this acquired coagulopathy among other more traditional diagnostic manifestations of SLE.