A50-07 Severe Babesiosis With Multiorgan Failure Requiring Red Cell Exchange Transfusions: A Case Series

Abstract Babesiosis is a parasitic infection caused by Babesia microti and is transmitted by the Ixodes scapularis tick. Immunocompromised, elderly, or asplenic patients are particularly predisposed to severe disease. Complications include hemolytic anemia, thrombocytopenia, hepatic failure, renal failure, and septic shock. Red blood cell exchange (RCE) transfusion is considered in high-grade parasitemia or evidence of organ dysfunction. We report three patients with severe babesiosis and multiorgan failure requiring RCE in our intensive care unit within the same month, with varying outcomes. The first, a 59-year-old male who presented with fevers, anemia, thrombocytopenia, renal failure, severe acute liver injury, and parasitemia of 15%. Despite early initiation of RCE, azithromycin, and atovaquone, he deteriorated rapidly, developing Acute Respiratory Distress Syndrome and multiorgan failure requiring intubation, vasopressors, and emergent renal replacement therapy. He passed away within 48 hours of admission. The second, a 42-year-old male arborist with multiple sclerosis on ocrelizumab and intravenous immunoglobulin, presented with altered mental status and was found to have a parasitemia of 21%, pancytopenia, severe hyponatremia, and acute kidney injury. He underwent two RCEs and received azithromycin and atovaquone. His hospital course was complicated by sepsis-induced cardiomyopathy with an ejection fraction of 35%, which improved to 65% once the infection started to clear. He recovered well and was discharged on oral antibiotics. The third, a 77-year-old asplenic male, presented with fever, acute liver injury, and parasitemia of 23.8%. He also tested positive for a recent Lyme infection. He underwent an RCE and was treated with azithromycin, atovaquone, clindamycin, and ceftriaxone. He improved swiftly and was discharged on a prolonged outpatient regimen due to relapse risk with asplenia. This case series demonstrates the varied presentation of severe babesiosis. While parasitemia thresholds (e.g. 10%) are commonly used to guide transfusion, recent literature suggests that end-organ dysfunction may better correlate with mortality. The proximity of these patients within Northern New Jersey underscores the importance of vector awareness and early clinical suspicion. Prompt diagnosis, aggressive antimicrobial therapy, and red cell exchange transfusion are the cornerstones of management of severe babesiosis. This abstract is funded by: None