One man, three tick-borne illnesses

A 70-year-old man presented to the emergency department with fevers, ankle edema and nausea following a presumed insect bite on his ankle 1 month prior. On examination, he was febrile and had left leg pain with passive range of motion. Laboratory studies revealed anemia, thrombocytopenia, acute kidney injury and elevated aminotransaminases. Due to his recent travel to the Northeastern United States, he was suspected of having a possible tick-borne illness. Serologies were positive for Borrelia burgdorferi, Anaplasma phagocytophilum and Babesia microti, and the patient was diagnosed with Lyme disease, babesiosis and anaplasmosis. He was treated with doxycyline, atovaquone and azithromycin, leading to resolution of symptoms. While co-infection with Lyme disease is common, infection with three tickborne illnesses at one time is relatively rare.