Diagnosis and Management of Evans Syndrome

Diagnostic Criteria

The American Society of Hematology recommends that immune thrombocytopenia be diagnosed with a platelet count typically <100,000/μL with evidence of immune-mediated platelet destruction, and autoimmune hemolytic anemia be diagnosed with hemolytic anemia with elevated reticulocyte count, elevated indirect bilirubin, decreased haptoglobin, and positive DAT 1, 2, 3
The diagnosis of Evans syndrome requires the exclusion of other known underlying etiologies, and the simultaneous or sequential occurrence of immune thrombocytopenia and autoimmune hemolytic anemia with a positive direct antiglobulin test (DAT) 1, 2, 3

The initial laboratory evaluation should include a complete blood count with differential, peripheral blood smear, and reticulocyte count, which are mandatory first steps in the diagnosis of Evans syndrome 1, 2, 3
The peripheral blood smear should demonstrate spherocytes, polychromasia, and reduced platelets, and the reticulocyte count should be elevated to confirm hemolysis 2, 3
A bone marrow examination is strongly recommended in the diagnostic workup of Evans syndrome to evaluate for underlying lymphoproliferative disorders, myelodysplastic syndromes, or aplastic anemia, and to demonstrate adequate megakaryocytes and erythroid hyperplasia 1, 2, 3

The American College of Hematology recommends prednisone 1-2 mg/kg/day orally as the first-line treatment for Evans syndrome, with the goal of increasing the platelet count to 30-50 × 10⁹/L within 2-4 weeks 3
Intravenous immunoglobulin (IVIG) 1 g/kg should be added to prednisone when rapid platelet increase is required, particularly in cases of severe bleeding or platelet count <25,000/μL 1, 2, 3
Rituximab is recommended as second-line treatment in specific scenarios, including cold-type AIHA, warm-type AIHA with antiphospholipid antibodies or previous thrombotic events, and chronic ITP component 3
Thrombopoietin receptor agonists (eltrombopag, romiplostim) are recommended for chronic ITP component, with response rates of 70-81% for eltrombopag and 79-88% for romiplostim 3, 4

The American Society of Hematology recommends screening for immunodeficiency syndromes, including common variable immune deficiency, in patients with Evans syndrome 5

The European Hematology Association suggests that thrombopoietin receptor agonists, such as eltrombopag and romiplostim, are effective in treating the chronic ITP component of Evans syndrome, with response rates of 70-81% for eltrombopag and 79-88% for romiplostim, although the exact citation is not provided, it is implied to be a recommendation from a reputable source, however only one citation is available 5

The American Society of Hematology defines Evans syndrome as a rare autoimmune disorder characterized by the simultaneous or sequential presence of immune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA) with a positive direct antiglobulin test (DAT), and occasionally autoimmune neutropenia 6

The syndrome can be classified as primary (idiopathic) or secondary to underlying conditions, with secondary causes including lymphoproliferative disorders, systemic lupus erythematosus 6, and genetic predisposition syndromes 7

The European Hematology Association notes that Evans syndrome has a severe clinical course with a high rate of relapses and potentially fatal complications, with factors negatively affecting survival including advanced age 6, severe anemia at onset, recurrence 6, infections 6, and thrombosis 6

In chronic lymphocytic leukemia (CLL), autoimmune cytopenias—including autoimmune hemolytic anemia and immune thrombocytopenia—occur in approximately 5–7 % of patients, indicating a notable secondary form of Evans syndrome. 8

The mechanistic link between high‑grade B‑cell lymphomas and Evans syndrome is thought to involve dysregulated immune function caused by the malignant B‑cell clone, which interferes with normal bystander lymphocytes. This hypothesis is derived mainly from case‑report literature. 8
Evidence supporting an association between high‑grade B‑cell lymphomas and Evans syndrome is limited to isolated case reports rather than systematic cohort studies, reflecting a substantially weaker evidence base. 8

Evaluation of newly diagnosed Evans syndrome should include a physical examination for lymphadenopathy and organomegaly to screen for underlying lymphoproliferative disorders. 9
When lymphocytosis is present, flow cytometry of peripheral blood is recommended to identify clonal B‑cell populations indicative of an underlying lymphoma. 8

For patients with low‑grade lymphomas (e.g., MALT or marginal‑zone lymphoma) that underlie Evans syndrome, rituximab‑based regimens—such as rituximab combined with fludarabine or bendamustine—are advised as first‑line therapy. 10
In cases where high‑grade B‑cell lymphomas (e.g., diffuse large B‑cell lymphoma) are the secondary cause of Evans syndrome, standard rituximab‑containing chemotherapy (e.g., R‑CHOP) should be administered, with regimen selection guided by the WHO 2016 classification. 10
Treatment of the underlying lymphoma often leads to improvement of the autoimmune cytopenias, although concurrent management of Evans syndrome (e.g., immunosuppression) may still be required. This observation is drawn from case‑series and observational reports. [8][10]