Absence of small-vessel abnormalities in alternating hemiplegia of childhood

Objective: To investigate whether Japanese patients with alternating hemiplegia of childhood (AHC) have the similar small-vessel abnormalities in skin reported in European patients with AHC. Methods: Electron microscopic observation of biopsied skin specimens were carried out in six Japanese patients with AHC. All patients (aged 5–17, all boys) had been diagnosed with AHC through their typical clinical courses and symptoms. Results: No abnormal findings in both endothelial cells and smooth muscle cells in skin small-vessels were obtained in the present study, either in the five flunarizine responders or in the one non-responder. Conclusions: From our observations, we hypothesized that there may be some subtypes of AHC. The diverse clinical courses in patients with AHC and the differing efficacy of flunarizine treatment could be explained because of the heterogeneity of AHC subtypes.