Transfusion‐transmitted babesiosis in a patient with sickle cell disease undergoing chronic red cell exchange

Abstract

Background Prior to laboratory‐based blood donor screening for Babesia, transfusion‐transmitted babesiosis (TTB) was a leading infectious risk to the blood supply in the United States. Case Report A 30‐year‐old man with sickle cell disease (SCD) who had been on a chronic automated red cell exchange (RCE) regimen since childhood, presented approximately 2 months after an RCE, with fever, neck pain, and photophobia. Meningitis was excluded, and he was discharged. He presented again 2 days later with persistent fever, chills, headache, fatigue, and loss of appetite. Results On examination, the patient was febrile but hemodynamically stable. Intra‐erythrocytic inclusions were identified on a peripheral blood smear (<0.5%). B. microti IgM and IgG titers were >1:320 (Reference <1:20) >1:1024 (Reference <1:64), respectively. B. microti was confirmed by nucleic acid testing. The patient lived in a Babesia endemic state but had no risk factors for tick‐borne acquisition. Of the 65 units he received in the preceding 6 months, 58 had been screened for Babesia. One of the donors of the 7 untested units was B. microti seropositive (titer 1:128; Reference 1: 64). The donor was asymptomatic and resided in a state in which Babesia screening was not required. He reported traveling in the year before his donation. Conclusion Although rare, TTB is still possible despite regional screening, underscoring the need for provider vigilance and education, especially in non‐endemic areas. Patients with SCD are particularly vulnerable given their high frequency of transfusion and complex needs requiring blood procurement from states where Babesia screening is not mandatory.