What is the recommended treatment algorithm for warm autoimmune hemolytic anemia, including first‑line, second‑line, and options for refractory disease?

Treatment of Warm Autoimmune Hemolytic Anemia (AIHA)

First-Line Treatment: Corticosteroids

Corticosteroids are the definitive first-line treatment for warm AIHA, with effectiveness in 70-85% of patients. 1, 2, 3

Dosing Strategy Based on Severity:

• Grade 1 (Mild): Hemoglobin <LLN to 10.0 g/dL requires close monitoring without immediate corticosteroid therapy 3

• Grade 2 (Moderate): Hemoglobin <10.0 to 8.0 g/dL requires oral prednisone 0.5-1 mg/kg/day 3, 4

• Grade 3-4 (Severe): Hemoglobin <8.0 g/dL or transfusion indicated requires prednisone 1-2 mg/kg/day (oral or IV depending on symptoms) with hospital admission for close monitoring 3, 4

• For severe/acute presentations requiring IV therapy: High-dose IV methylprednisolone ≥1 mg/kg daily should be administered as early as possible 3, 4

Steroid Tapering:

• Corticosteroids should be slowly tapered over 6-12 months once response is achieved 5
• Monitor hemoglobin levels, reticulocyte count, bilirubin, LDH, haptoglobin, and direct antiglobulin test (DAT) to evaluate response 3
• Complete normalization of hemoglobin and laboratory parameters should be the treatment goal 3

Second-Line Treatment for Refractory/Relapsed Disease

Rituximab (375 mg/m² weekly for 4 weeks) has become the preferred second-line treatment with 70-80% effectiveness and is increasingly used before splenectomy. 3, 4, 5, 6

Alternative Second-Line Options:

• Splenectomy: Effective in approximately 70% of cases with a presumed cure rate of 20%, but rituximab is now preferred due to surgical complications 1, 5, 6

• Immunosuppressive agents can be added to corticosteroids for severe or refractory cases:

  • Azathioprine 150 mg/day 2
  • Mycophenolate mofetil 2, 5
  • Cyclosporine 2.5-3 mg/kg/day (adjusted for target trough levels 100-150 ng/mL) 2, 3
  • Cyclophosphamide 1-2 mg/kg/day 3, 5

• Intravenous immunoglobulin (IVIG): 0.3-0.5 g/kg or 1 g/kg over 1-2 days provides rapid but temporary improvement, particularly useful for acute bleeding risk 2, 3

Third-Line and Refractory Options

For patients failing corticosteroids, rituximab, and standard immunosuppressants:

• Plasma exchange (TPE) combined with low-dose IVIG and rituximab may be considered in severe refractory cases 7

• High-dose cyclophosphamide as a last resort option 5, 6

• Alemtuzumab as a last resort option 5, 6

• Danazol as an additional therapy 5, 6

Critical Management Caveats

• Avoid IV anti-D in patients with AIHA, as it can exacerbate hemolysis 3, 4

• For symptomatic patients, use minimum necessary RBC transfusion units despite potential difficulty in crossmatching 3

• Weekly platelet count and hemoglobin monitoring during initial treatment is crucial 2

Special Context: AIHA in Chronic Lymphocytic Leukemia (CLL)

• Patients with stable CLL and "simple autoimmunity" should receive corticosteroids first-line 1

• Rituximab should be considered before splenectomy in CLL-associated AIHA with warm antibodies 1

• Autoimmune cytopenias not responding to conventional therapy are indications for initiating CLL-directed treatment 1

• Patients with immune-mediated cytopenias have better outcomes than those with bone marrow infiltration 1, 2