Legionellosis presenting as singultus and external ophthalmoplegia

We report a 71-year-old man with legionellosis, who presented with abducens nerve palsy, singultus, confusion, memory impairment, ataxia, and hyporeflexia. Legionella pneumonia was diagnosed on the basis of detection of Legionella pneumophila antigen in the urine. The cerebrospinal fluid was negative for the antigen and antibody, but an oligoclonal band was detected, and the IgG index was elevated. It was speculated that an undetermined immune-mediated mechanism had contributed to the development of the neurological manifestations.