Miller Fisher syndrome in infancy.

Miller Fisher syndrome (MFS) is characterized by the triad of ataxia, areflexia and ophthalmoplegia. It is exceptional for infants to be involved. Two infants, aged 11 and 16 months, developed acute-onset MFS. Both patients had prodromal upper respiratory tract infection. Pupillary responses to light, strength and sensation modalities were preserved. One patient was lethargic for a day; the electroencephalogram disclosed slightly slow background activity that later became normal. The other received high-dose intravenous immunoglobulins for 5 consecutive days starting at once on admission; within the next 7 days he became asymptomatic. Increased cerebrospinal fluid protein content and delayed nerve conduction studies with prolonged distal latencies were encountered in both patients.