Clot waveform analysis for perioperative hemostatic monitoring of arthroscopic synovectomy in a pediatric patient with hemophilia A and inhibitor receiving emicizumab prophylaxis

Emicizumab reduces bleeding in patients with hemophilia A and inhibitors (PwHA-I). Coagulation potential during the perioperative period in emicizumab-treated PwHA-I undergoing surgery remains to be evaluated. We describe a 14-year-old boy with HA-I receiving emicizumab prophylaxis who experienced arthroscopic synovectomy. He was treated with a bolus infusion of recombinant factor VIIa (rFVIIa; 80 μg/kg) immediately before surgery, and treatment continued at the same dose every 3 h on day 1, every 4 h on day 2, and every 6 h on day 3. Treatment with rFVIIa was discontinued on day 4. No perioperative bleeding or thrombotic events were observed. Coagulation potential throughout the perioperative period was retrospectively assessed with an easy-to-use clot waveform analysis (CWA). Measurements from CWA returned to within or near the normal range, suggesting successful hemostatic management. Coagulation potentials assessed by CWA showed a significant correspondence with those from a thrombin generation assay (TGA) that is already in use. CWA and TGA could both provide useful data for assessing coagulation potential in the perioperative hemostatic management of emicizumab-treated PwHA-I.

Prophylaxis Using a Mixture of Plasma-Derived Activated Factor VII and Factor X (pdFVIIa/FX) in a Patient with Hemophilia B Complicated by Inhibitors and Allergy to Factor IX Concentrates: A Case Report

Treating patients with hemophilia and inhibitors is often problematic. The presence of inhibitors negatively impacts the effectiveness of treatment to achieve hemostasis especially in patients with hemophilia B, owing mainly to allergic reactions to factor IX (FIX) concentrates and the low success rate of immune tolerance therapy. A 9-month-old boy had intracranial hemorrhage and was diagnosed with hemophilia B. After replacement therapy, he developed inhibitors and an allergic reaction to FIX. Prophylactic therapy was initiated with recombinant activated factor VII (rFVIIa) and later switched to pdFVIIa/factor X (FX; 120 μg/kg as the FVII dose, every other day) because of a recurrence of intracranial hemorrhage. Since then, he remained well without life-threatening bleeding for more than 2 years. Our case suggests that pdFVIIa/FX may be useful for prophylactic therapy in hemophilia B complicated by inhibitors and allergic reaction to FIX concentrates.

Rare and unusual case of anti-factor XI antibodies in patient with plasma cell leukemia

Background

The acquired inhibitors of coagulation have been observed in very rare cases of monoclonal gammopathies. We report a very rare case of anti-factor XI antibodies in patient with plasma cell leukemia (PCL).

Case presentation

This is a 59-year-old male patient without pathological history, admitted to the nephrology department for management of renal insufficiency and anemia syndrome. The history and physical examination revealed stigmata of hemorrhagic syndrome including hemothorax and hemoptysis. The hemostasis assessment showed an isolated prolonged activated partial thromboplastin time (APTT) with APTT ratio = 2.0.The index of circulating anticoagulant (37.2%) revealed the presence of circulating anticoagulants. The normalized dilute Russell viper venom time ratio of 0.99 has highlighted the absence of lupus anticoagulants. The coagulation factors assay objectified the decrease of the factor XI activity corrected by the addition of the control plasma confirming the presence of anti-factor XI autoantibodies. In addition, the blood count showed bicytopenia with non-regenerative normocytic normochromic anemia and thrombocytopenia. The blood smear demonstrated a plasma cell count of 49% (2842/mm3) evoking PCL. The bone marrow was invaded up to 90% by dystrophic plasma cells. The biochemical assessment suggested downstream renal and electrolyte disturbances from exuberant light chain production with abnormalities including hyperuricemia, hypercalcemia, elevated lactate dehydrogenase, non nephrotic-range proteinuria and high level of C reactive protein. The serum protein electrophoresis showed the presence of a monoclonal peak. The serum immunofixation test detects the presence of monoclonal free lambda light chains. He was treated with velcade, thalidomide and dexamethasone. The patient died after 2 weeks despite treatment.

Conclusion

Both PCL and anti-factor XI inhibitors are two very rare entities. To the best of our knowledge, this is the first reported case of a factor XI inhibitor arising in the setting of PCL. Factor inhibitors should be suspected in patients whose monoclonal gammopathies are accompanied by bleeding manifestations.

Systematic review of the presentation of coagulation factor VIII inhibitors in rheumatic diseases: A potential cause of life-threatening hemorrhage

OBJECTIVES

To provide a comprehensive review regarding the clinical presentation of acquired factor VIII (FVIII) inhibitors, also known as "acquired hemophilia," in patients with rheumatic diseases.

METHODS

A systematic MEDLINE search was conducted to identify English-language articles published from 1993 through January 10, 2012, providing details regarding the clinical presentation, laboratory evaluation, and management of a patient(s) with newly or previously diagnosed autoimmune disease coexistent with an acquired FVIII inhibitor.

RESULTS

In total, 49 patients fulfilled the criteria for inclusion in the review; the greatest percentage (24.5%) had systemic lupus erythematosus, followed by rheumatoid arthritis (16%). The majority (78%) presented with spontaneous mucocutaneous or muscular bleeding. Prolonged activated partial thromboplastin time (aPTT) was identified in all of the 45 patients for whom results were provided. Five patients presented with an asymptomatic prolonged aPTT, which was attributed to a lupus anticoagulant in two patients, only one of whom actually had a coexisting lupus anticoagulant. Invasive procedures led to serious bleeding in both of these patients, one of whom died as a result. The majority (59%) of patients experienced complete or partial remission of their inhibitors, most (96%) after systemic eradicative therapy. A total of three (6%) patients died as a direct result of FVIII inhibitors.

CONCLUSIONS

Although acquired FVIII inhibitors are rare in patients with autoimmune diseases, prompt diagnosis is essential to avoid extensive bleeding, which could be life threatening. Treatment requires eradication of the factor inhibitors. Rheumatologists must be able to distinguish acquired FVIII inhibitors from lupus anticoagulants.