A patient with relapsed/refractory B-cell acute lymphoblastic leukemia developed babesiosis before allogeneic hematopoietic cell transplantation while on atovaquone for Pneumocystis jirovecii pneumonia prophylaxis. Despite receiving a prolonged course of atovaquone and azithromycin until whole-blood Babesia microti DNA was no longer detected by polymerase chain reaction, her post-transplant course was complicated by relapsed babesiosis. We investigate the potential host and parasite characteristics causing relapsing/persistent infection.
- Babesia microti
- hematopoietic cell transplantation
- immunocompromised host
- tick-borne pathogens