Concurrent babesiosis and ehrlichiosis in an elderly host.

An 85-year-old man, actively infected with Babesia microti and Ehrlichia chaffeensis, presented with fatigue and thrombocytopenia. He developed rhabdomyolysis and multiple organ failure, which led to death 6 days after initial presentation. To our knowledge, concurrent acute disease due to these 2 organisms has not been reported previously, although serologic studies have shown that some patients acquire both infections in life.