Developmental stutter in a patient with callosal agenesis disappears during steroid therapy.

A 10-year-old left-handed girl with a developmental stutter and agenesis of the corpus callosum with associated hydrocephalus ceased stuttering immediately upon initiation of steroid therapy for colitis. Steroid taper resulted in a recurrence of the stutter and resumption for treatment of recrudescent colitis caused its disappearance again. Baseline agenesis of the corpus callosum with hydrocephalus and the patient's course in the face of the known effects of steroids on white matter lend support to the hypothesis that stuttering reflects anomalous dominance and/or atypical interhemispheric connectivity, as evidenced by the fact that presumed alterations of white matter tracts affected speech rhythms/stuttering.