Bleeding of Unknown Cause: a Swiss Case-control Study

Patients with bleeding of unknown cause are included. At baseline, blood will be drawn to evaluate the hemostatic profile. Findings are compared to a control group of healthy individuals. Patients and controls are followed for 3 years.

Inclusion criteria

• Man with ISTH BAT>3. If the calculated score includes a surgical bleeding, then two other items of the score should be >0
• Woman with ISTH BAT >5 points. If the calculated score includes a surgical or a postpartum bleeding, then two other items of the score should be >0

Exclusion criteria

• Ongoing pregnancy
• Intake of antithrombotic treatment or non-steroidal anti-inflammatory drugs for least 10 days at time of blood collection
• Intake of antifibrinolytic or blood product administration (factor concentrate, frozen fresh plasma, prothrombin complex concentrate) for least 14 days before blood collection
• Active cancer (defined as cancer diagnosis within the last five years or treatment within the two last years before study inclusion)
• Active autoimmune disease
• Active chronic inflammatory disease
• Severe liver disease (cirrhosis > Child A)
• Renal insufficiency stage 3
• Active or recent infection (within the last 30 days)
• Recent hospitalization (<3 months)
• Recent surgery (<3 months)
• Recent trauma requiring medical intervention (<3 months)