Purpose: In patients with progressive encephalopathy, hypsarrhythmia, and optic atrophy (PEHO) syndrome, the pathophysiology underlying early progressive cerebellar and brainstem degeneration and severe epilepsy is unknown. Because insulin-like growth factor (IGF)-1 has been shown significantly to promote survival of cerebellar neurons, we wanted to see if the IGF system played a role in the pathogenesis of cerebellar atrophy.
Methods: We used a sensitive enzyme immunoassay kit for measuring cerebrospinal fluid (CSF) IGF-1 and insulin-like growth-binding protein (IGFBP)-3 in four groups of patients: PEHO syndrome patients (eight), PEHO-like patients (seven), age-matched controls (31), and patients with other types of cerebellar atrophy (11).
Results: Patients with PEHO syndrome and those with other progressive, degenerative cerebellar diseases had lower levels of CSF IGF-1 than the controls with other neurologic diseases. The CSF IGF-1 also allowed us to differentiate the "true" PEHO patients from the "PEHO-like" patients (those with similar clinical symptoms but without the typical neuroophthalmologic or neuroradiologic findings). The concentrations of IGFBP-3 did not significantly differ in any of the patient or control groups studied.
Conclusions: CSF IGF-1 levels might be used as a marker of the degeneration of neurons in specific areas.