**6. Conclusion**

Bleeding is a rare but potentially severe complication of aPL and APS. Its etiology is heterogeneous; aPL-positive patients can develop bleeding due to thrombocytopenia, acquired coagulation factor deficiencies (predominantly hypoprothrombinemia), TMAs, or the adverse events of antithrombotic therapy (mostly with warfarin). However, thromboembolic events represent the most dangerous complications for aPL-positive patients, and the thrombotic risk remains clinically relevant even in the presence of hemorrhage in the majority of patients.

The management of bleeding is challenging. It is necessary to balance both thrombotic and bleeding stimuli and to continue antithrombotic prevention or therapy for as long as possible. The individual approach is critical for a favorable clinical outcome. Specific treatment can be necessary for eliminating the cause of bleeding and achieving its control. Immunosuppressive agents, especially corticosteroids, are the first-choice treatment for aPL-associated thrombocytopenia, coagulation factor deficiencies, CAPS, and DAH. Other immunosuppressive or immunomodulatory agents can be efficient in case of unsatisfactory clinical response. Rituximab appears to be the most promising alternative. Corticosteroids are also fundamental for the diffuse alveolar hemorrhage, albeit firstly for the correction of consequential adrenal insufficiency. aPL-positive patients receiving antithrombotics should be monitored closely, and their compliance ensured, especially in the scenario with the high-intensity or combined antithrombotic therapy.
