Alternating hemiplegia in childhood: a cross-sectional study

Six patients with alternating hemiplegia in childhood (AHC) were followed, some of them up to childhood. Progressive intellectual deterioration and disturbance of pyramidal, extrapyramidal and cerebellar functions were found in all of them. Multimodal evoked potential abnormalities, changes of sleep structure and HMPAO-SPECT results were correlated with increasing clinical handicap. In older patients increases in the plasma level of lactate, as well as in the lactate: pyruvate ratio, were revealed, accompanied by elevated inorganic phosphate (Pi) values on 31P MR spectroscopy. These findings support the hypothesis of a possible secondary mitochondrial deficit in AHC. However, no specific bioptic changes (muscle, skin, or buccal mucous membrane) were found, and thus the etiology of AHC remains unclear.