Case 1: A 40-year-old male with antiphospholipid syndrome A 40-year-old Caucasian male with history of antiphospholipid syndrome (APS) was admitted to the Hospital Clinic Barcelona with hemoptysis, acute respiratory failure and thrombocytopenia. Diagnosis of APS had been made at the age of 27 years after an episode of pulmonary embolism, and detection of positive lupus anticoagulant and high levels of IgG anticardiolipin antibodies. Since then, he received oral anticoagulants (acenocoumarol), but despite this treatment he suffered an inferior vena cava thrombosis at the age of 31 years.

On admission to the emergency room, the patient reported an episode of sudden hemoptysis and dyspnea earlier that morning. His current medication was acenocoumarol with an international normalized ratio (INR) of 3.2, performed 5 days prior.

The patient was in a regular state and chest examination revealed pulmonary crackles in both lungs. Laboratory tests showed a low platelet count (8x10⁹/L) and high creatinine levels (3.6 mg/dL). Chest X-ray disclosed bilateral pulmonary infiltrates.

Learning Objectives At the end of this workshop participants will be able to:

• Explain the main challenges in the differential diagnosis of thrombocytopenia in patients with SLE

• Describe the options for the treatment of thrombocytopenia in SLE

• Enhance clinical awareness of potential severe complications of hematological problems in SLE