Reverse Shapiro's syndrome--an unusual cause of fever of unknown origin.

Reverse Shapiro's syndrome was first described by Hirayama et al. in a girl with periodic hyperthermia associated with complete agenesis of the corpus callosum. Here we report another such case in a 9-month-old girl presenting with fever of unknown origin since the age of 7 months. On examination, she had mild hypotonia with delayed developmental milestones. No other neurological or physical abnormalities were noted. The cause of her prolonged fever of unknown origin was investigated and all results were negative. Her brain magnetic resonance images showed agenesis of the corpus callosum. On the basis of the previous literature, we suggest that the periodic hyperthermia of this girl was caused by dopaminergic denervation of the hypothalamic thermoregulatory center. Treatment with dopamine agonists (levodopa plus carbidopa) failed to control the hyperthermia.