What are the diagnostic criteria for Evans syndrome (a disorder characterized by autoimmune hemolytic anemia and immune thrombocytopenia)?

From the Guidelines

Evans syndrome is diagnosed when a patient has both autoimmune hemolytic anemia (AIHA) and immune thrombocytopenia (ITP) occurring simultaneously or sequentially, without any underlying cause, as supported by the most recent guidelines 1. The criteria for diagnosis include:

• Presence of AIHA: Positive direct antiglobulin test (DAT) and evidence of hemolysis (elevated reticulocyte count, increased lactate dehydrogenase, decreased haptoglobin)
• Presence of ITP: Platelet count <100,000/μL with normal or increased megakaryocytes in the bone marrow
• Exclusion of other underlying conditions: Thorough evaluation to rule out systemic lupus erythematosus, lymphoproliferative disorders, or other autoimmune diseases

To diagnose and manage Evans syndrome:

• Perform complete blood count, reticulocyte count, DAT, and peripheral blood smear
• Check lactate dehydrogenase, haptoglobin, and bilirubin levels
• Conduct bone marrow examination to exclude other causes
• Screen for underlying autoimmune disorders or malignancies

Treatment typically involves immunosuppression:

• First-line: Corticosteroids (e.g., prednisone 1-2 mg/kg/day for 3-4 weeks, then taper) 1
• Second-line: Rituximab (375 mg/m² weekly for 4 weeks) or splenectomy
• Other options: Intravenous immunoglobulin, cyclosporine, mycophenolate mofetil, or thrombopoietin receptor agonists

Monitor patients regularly for response to treatment and potential complications, as the condition can have a significant impact on morbidity, mortality, and quality of life 1. Long-term follow-up is essential due to the chronic and relapsing nature of the condition. Understanding Evans syndrome as a combined autoimmune disorder affecting both red blood cells and platelets helps explain its complex presentation and management challenges, and the goal of treatment is to suppress the autoimmune response while minimizing side effects of immunosuppression 1.

From the Research

Diagnostic Criteria for Evans Syndrome

The diagnostic criteria for Evans syndrome, a disorder characterized by autoimmune hemolytic anemia and immune thrombocytopenia, involve a combination of clinical and laboratory findings. The key features include:

• Autoimmune hemolytic anemia (AIHA) and immune thrombocytopenia (ITP) occurring simultaneously or sequentially 2, 3, 4, 5, 6
• Presence of autoantibodies against red blood cells and platelets, as evidenced by a positive direct antiglobulin test (DAT) 3, 5
• Exclusion of other underlying conditions, such as lymphoproliferative diseases and systemic lupus erythematosus (SLE) 2, 4

Laboratory Findings

Laboratory findings that support the diagnosis of Evans syndrome include:

• Hemolysis, as indicated by elevated lactate dehydrogenase, low haptoglobin, and elevated bilirubin levels 3
• Thrombocytopenia, with a platelet count typically below 100 × 10^9/L 3, 5
• Anemia, with a hemoglobin level typically below 10 g/dL 3, 5
• Presence of spherocytes on peripheral blood smear 3

Clinical Presentation

The clinical presentation of Evans syndrome can vary, but common symptoms include:

• Fatigue, weakness, and shortness of breath due to anemia 2, 3
• Bleeding manifestations, such as petechiae, purpura, and bleeding from the mouth and gums, due to thrombocytopenia 3, 6
• Jaundice and dark urine due to hemolysis 3