Abstract
Anaplasma phagocytophilum is the causative agent of human granulocytic anaplasmosis (HGA), a tick-borne illness with increasing incidence since being described in the 1990s. Importantly, the presentation can be vague, yet prompt treatment is paramount. An 81-year-old Caucasian female was hospitalized in Cincinnati, Ohio, for fever and confusion following prolonged outdoor exposure in Emlenton, Pennsylvania. She initially was treated for sepsis from presumed community-acquired pneumonia; however, the combination of leukopenia, thrombocytopenia, and elevated liver enzymes prompted empiric tick-borne illness consideration and treatment with rapid resolution in symptoms. Early recognition of HGA can reduce unnecessary treatments and improve patient outcomes.