The investigation of the significance of a positive direct antiglobulin test in blood donors.

Sixty-two samples from 62 donors were investigated to determine the significance of warm IgG autoantibodies that were detected using a gel system during compatibility testing. The presence of autoantibodies on the red cells was confirmed by elution studies. Twelve of 23 strongly positive samples, 7 of 19 moderately positive samples, and 6 of 11 weakly positive samples were studied. The remaining nine samples were found positive during crossmatching, then negative when it was repeated. These nine samples were not included in this study. With a tube test, most of the antibodies had titers from 4 to 8. IgG subclass studies showed that 14 of 25 samples with reactive eluates contained IgG1, one contained IgG1+IgG2, one contained IgG1+IgG4, and two contained IgG1+IgG3 weak. The frequency of donors with a positive direct antiglobulin test (DAT) was approximately 1 in 3000 and males were twice as likely to be DAT positive (8 females vs. 17 males in this study). None of the donors had hemolysis. Two donors showed low-titer anticardiolipin antibodies. We conclude that DAT-positive donors can be a problem during compatibility testing when sensitive methods are used.

Surgery-associated acquired hemophilia A.

We present two patients who acquired factor VIII antibodies in the immediate postoperative period. One patient was receiving warfarin that was temporarily discontinued but reintroduced after the procedure. Preoperatively, none gave a history of bleeding, even with past surgeries, and both had normal coagulation tests. Within days of surgery, hemorrhage with prolonged activated partial thromboplastin time, low factor VIII levels, and demonstrable factor VIII antibodies were observed. For the patient who was receiving warfarin the severe bleeding was attributed, at the beginning, only to the high international normalized ratio (INR), which resulted in a fatal delay in diagnosis and appropriate treatment. We would like to raise awareness of surgery as a precipitating cause of acquired hemophilia, which is something to be considered with unusual postoperative bleeding. This syndrome is remarkable for its abrupt onset within days of surgery, severe bleeding but potential successful outcome with combined hemostatic control with recombinant activated FVII (rFVIIa) and elimination of the antibody by immunosuppression.

Cardiac tamponade due to post-cardiac injury syndrome in a patient with severe haemophilia A and HIV-1 infection.

An 18-year-old man with severe haemophilia A (FVIII:C < 1%) and human immunodeficiency virus 1 (HIV-1) infection was admitted to the hospital with fever and chest pain for 7 days. Eight weeks prior to his admission he had an accident for which he underwent, at another hospital, clinical and laboratory examination that revealed bone fractures of the nose cavity, and he was given factor VIII concentrates for seven days due to nasal bleeding. On admission, chest roentgenogram showed a large cardiac silhouette and echocardiography confirmed the presence of a large quantity of pericardial fluid. A presumptive diagnosis of the post-cardiac injury syndrome was made and he was given anti-inflammatory drugs plus infusion of recombinant factor VIII concentrate (35 units kg-1 b.i.d.). On the seventh day he exhibited cardiac tamponade for which he underwent subxiphoid pericardiotomy with drainage of approximately 1500 mL of bloody exudate. He had an uncomplicated recovery and 10 days later he left hospital. He was given a continuous prophylactic treatment of 15 units kg-1 of recombinant FVIII every 2 days for 6 months, and 30 months after this episode the patient is free of any symptom.