A50-39 Turning the Tide: Exchange Transfusion in Life-Threatening Babesiosis With Concurrent Lyme Disease

Introduction Babesiosis is a zoonotic illness caused by Babesia microti and transmitted by Ixodes tick. We present a case of life-threatening Babesiosis with hemolytic anemia, successfully treated with Red blood cell exchange transfusion. Case report An eighty-six-year-old female with history of Atrial Fibrillation, Ulcerative Colitis, presented with dyspnea, productive cough, fatigue, altered mentation of three days duration. Five days before presentation, she was diagnosed with Bell’s palsy due to Lyme disease. She denied fever, travel, blood transfusion. She was afebrile, tachycardic, in mild respiratory distress requiring 4L oxygen. Physical exam was remarkable for rhonchorous breath sounds. Laboratory findings are notable for hemoglobin 5.9 g/dL, thrombocytopenia 64000 cells/uL, undetectable haptoglobin, elevated liver enzymes, lactate dehydrogenase 1363 IU/L. Direct Coombs test was negative indicating nonimmune hemolysis. Serum creatinine normal. Lyme serology was positive for IgM and IgG. Imaging demonstrated multifocal pneumonia. Peripheral blood smear revealed Babesia microti with parasitemia of 13.5%. She was treated with Atovaquone and Azithromycin. Given the severity of hemolytic anemia, high parasitemia, and end-organ damage, red blood cell exchange transfusion was done. She had significant clinical improvement along with decreasing parasitemia to 7.6% following one exchange transfusion; without rebound parasitemia. Thereafter, parasitemia cleared with antibiotics alone, which she completed for a total of 14 days after first negative peripheral smear, along with Doxycycline for Lyme Disease. Discussion Severe Babesiosis, defined as parasitemia >4%, end-organ damage, and severe hemolytic anemia, usually occurs in immunocompromised, and asplenic population. Other risk factors include age>50 years, HIV/AIDS, malignancy etc. The presence of rash in a patient with Babesiosis should prompt investigation for concurrent tick-borne illnesses. Babesiosis presents as fever of unknown origin, hemolytic anemia, thrombocytopenia, liver or renal dysfunction, neurological impairment. Our patient had concurrent infection as evidenced by Bell’s palsy and positive Lyme serologies. In hemodynamically unstable patients with ongoing hemorrhage, splenic rupture should be suspected, albeit rare. On literature review, approximately 100 cases of severe babesiosis have been successfully treated with exchange transfusion. There are no universally accepted criteria for therapeutic apheresis in severe babesiosis, though recommended for high parasitemia >10%, end-organ damage (renal, pulmonary, or hepatic), and severe hemolysis, as seen in our patient. Rebound parasitemia has been reported, requiring additional exchange transfusions. Novel therapeutics such as combination of Tafenoquine and Atovaquone is being investigated for severe babesiosis. Our case demonstrates utilizing Exchange Transfusion, early in the course of severe babesiosis, can potentially mitigate end-organ damage and parasite burden. This abstract is funded by: None