Lyme Disease in Canada

We diagnosed severe human granulocytic anaplasmosis with secondary HLH, as well as coinfection with Lyme disease and Powassan virus. The patient completed a 10-day course of doxycycline for anaplasmosis and a 3-week course of ceftriaxone for presumed Lyme encephalitis, with complete recovery. Given his clinical improvement with antimicrobials, we did not start the patient on other treatments for HLH. He was discharged home after a 55-day admission to hospital. The patient was seen in follow-up 3 months after presentation and was clinically well, with complete resolution of hematologic derangements.