Multisystem flare of systemic lupus erythematosus presenting with severe warm autoimmune hemolytic anemia: A diagnostic and transfusion challenge

Abstract Introduction: Warm autoimmune hemolytic anemia (wAIHA) is a potentially life-threatening complication of systemic lupus erythematosus (SLE), affecting up to 10% of patients. Among these, 40–60% develop autoantibodies that interfere with crossmatching, rendering transfusion particularly challenging [1,2]. Prompt recognition and coordinated multidisciplinary management are crucial, especially when hemoglobin (Hb) levels fall below 5 g/dL. We present a complex case of wAIHA in the context of a multisystem SLE flare, highlighting diagnostic intricacies and transfusion strategies. Case Presentation: A 43-year-old woman with established SLE (diagnosed in 2016), previously treated with hydroxychloroquine and methotrexate, presented with fatigue, jaundice, dark urine, and right upper quadrant discomfort. She reported an unintentional 30 lb weight loss over six months. Vitals were stable. Physical examination revealed pallor, scleral icterus, and mild RUQ tenderness. Labs showed: Hb 3.3, MCV 112 , reticulocyte count 25.8%, LDH 1,136, indirect bilirubin 3.9 , and AST/ALT 765/755. Direct antiglobulin test was positive. Workup for viral hepatitis, acetaminophen toxicity, and autoimmune hepatitis was negative. RUQ ultrasound revealed hepatic echogenicity, gallbladder wall thickening, and a 5.3 × 5.4 × 5.9 cm uterine mass concerning for fibroid or endometrial pathology. Crossmatching failed to identify fully compatible RBC units due to broad-spectrum autoantibodies. The patient was premedicated with IV methylprednisolone and diphenhydramine and transfused with two units of the least incompatible RBCs. Her Hb increased to 7.2 g/dL without transfusion reaction. She received methylprednisolone 1 g IV daily for three days, followed by oral prednisone (1 mg/kg/day). Ongoing hemolysis and elevated liver enzymes prompted initiation of rituximab (375 mg/m² weekly for four weeks). Further evaluation included liver elastography, smooth muscle antibody testing, and a planned endometrial biopsy. At two-week follow-up, her Hb stabilized at 10.1 g/dL, LDH normalized, and transaminases improved to AST/ALT 75/83 U/L. Discussion: This case underscores the complexity of managing severe wAIHA in the context of a multisystem SLE flare. When compatible blood is unattainable, transfusing the least incompatible units under steroid cover is a validated and often necessary approach [3,4]. The patient's hepatic involvement and uterine mass required concurrent diagnostic consideration, emphasizing the importance of a broad differential in SLE flares. Rituximab is increasingly employed in refractory cases, achieving durable remission in over 60% of patients [5]. Our patient responded favorably, with sustained hematologic recovery and reduction in inflammatory markers. Conclusion: Severe wAIHA in SLE demands rapid diagnosis, interdepartmental collaboration, and flexibility in transfusion strategies. The least incompatible RBC transfusion, combined with immunosuppressive therapy, can be lifesaving. Comprehensive evaluation of systemic involvement is essential in such complex flares. Further studies are warranted to define the optimal sequencing of biologics like rituximab in acute management. References: Barcellini W, et al. Autoimmune hemolytic anemias in systemic lupus erythematosus. Autoimmun Rev. 2017;16(7):709–716. Packman CH. The clinical pictures of autoimmune hemolytic anemia. Transfus Med Hemother. 2015;42(5):317–324. Hill QA, et al. Management of drug-induced immune and secondary autoimmune hemolytic anemia. Br J Haematol. 2017;177(2):208–220. Petz LD, Garratty G. Immune Hemolytic Anemias. 2nd ed. Churchill Livingstone; 2004. Jäger U, et al. Rituximab in warm autoimmune hemolytic anemia: a multicenter retrospective study. Blood. 2016;127(15):1735–1739.