Standardization of Management of Warm Autoimmune Hemolytic Anemia
Authors: Thomas Nithin , Bowzard M Luisa , Sun Laura , Comiter Jacqueline , Gaddh Manila 
Published: December 2024

Background: Warm autoimmune hemolytic anemia (WAIHA) is a rare but serious disorder caused by antibodies active at normal body temperature that cause destruction of red blood cells leading to severe anemia . There are wide inter-provider variations in the current management of WAIHA that can cause confusion for the patient and patient-care teams leading to an overall negative effect on patient care. While some variation based on individual patient characteristics may be necessary, our goal was to develop an institutional algorithm for WAIHA management that reduced the variation as much as possible.

Methods: Our team included learners (medical student, fellow), interprofessional members (advanced practice provider, pharmacist) and a hematology attending, all of whom completed a Quality improvement (QI) training course conducted by our institution over 6 months. Available literature of warm AIHA management was reviewed and we developed a process map standardizing a method for diagnosis and initial management of WAIHA. We fostered buy-in from key stake holders by presenting our project at our institution's weekly Classical Hematology conferences, communicating periodically via group e-mails, and posting updates on our practice shared- drive. After obtaining feedback we instituted our first test of change. We performed retrospective chart review of patients with WAIHA diagnosis 2 years prior to our QI project to look at diagnostic workup and initial management, and how these compared with our process map.

Results: Our retrospective chart review identified 12 patients with WAIHA diagnosis- 3 patients with primary and 9 with secondary WAIHA. Secondary WAIHA was related to systemic lupus erythematosus(SLE) (3 patients), viral infections (3 patients) and 1 patient each with Chronic Lymphocytic leukemia (CLL), Common variable immunodeficiency(CVID) and post Hematopoietic stem cell transplant(HSCT). Patient with CVID was excluded for lack of active hemolysis. We noticed significant variations in diagnostic tests done and incomplete workup looking for an underlying secondary cause in patients identified as primary WAIHA. For initial management, 2 out of the 3 patients with primary WAIHA were started on prednisone while the 3rd was started on intravenous methyl prednisolone and transitioned to prednisone after 5 days. Initial daily prednisone dose varied between 80 mg(1 mg/kg), 60 mg(0.5 mg/kg) and 125 mg (~1.7 mg/kg). Tapering duration was 3 months, 9 months and unknown. 2 of these received Rituximab within 1 month and the 3rd at 6 months after diagnosis. Patients with secondary AIHA due to viral infections, SLE and CLL received varying regimens of steroids and Rituximab, and treatment of underlying SLE and CLL as applicable. Patient with WAIHA post HSCT (for secondary Myelodysplastic syndrome) had complicated clinical course. Treatment lines including Prednisone, splenectomy, Tacrolimus, Rituximab, Bortezomib, Daratumumab, Plasmapheresis, and Eculizumab, were marred with poor response. When compared with our process mapping for initial management of WAIHA there was wide variation in steroid selection, dosing, tapering and timing of Rituximab administration.

Conclusion: Above initial results shows that there was inter provider variability in the initial work up, steroid selection, dosing and timing of Rituximab. We are currently collecting data on patients that have been diagnosed and managed for WAIHA since the implementation of the process map, and are also developing our treatment algorithm further to include subsequent lines of treatment after the initial management. We hope this work on institutional standardization of management of WAIHA will ultimately help in improving patient outcomes.