Neurologic complications following the treatment of human Babesia microti infection with diminazene aceturate.

A 65-year-old man infected with Babesia microti failed to respond to therapy with oral chloroquine phosphate. He was then successfully dreated with diminazene aceturate, an experimental anti-protozoal agent. After his recovery from babesiosis, the patient developed acute idiopathic polyneuritis (Landry-Guillain-Barré Syndrome), which was probably related to his diminazene therapy.