ALTERNATING HEMIPLEGIA OF CHILDHOOD - REPORT OF A CASE HAVING A LONG HISTORY

We examined a patient with alternating hemiplegia of childhood (AHC) w ho had over a 23-year history of AHC to investigate the origin of the neurological deterioration with increasing age. Hemiplegic attacks had occurred consistently at a frequency of a few per week since infancy, and he first experienced attacks of cerebellar ataxia at the age of 2 3 years. Intellectual impairment, dysarthria, dystonic posturing, and a wide-based gait had been slowly progressive, but they had been stabl e since he turned twenty. The electromyographic response to transcrani al magnetic stimulation was normal between attacks and showed reversib le alteration during an attack. MRI revealed slight dilatation of the lateral ventricles, and MR angiography showed normal cerebral blood fl ow. Proton MR spectroscopy between attacks showed normal peak area rat ios for N-acetyl groups, choline-containing compounds, and creatine an d phosphocreatine, and it also demonstrated no lactic peak. I-123-IMP SPECT between attacks demonstrated diffuse cerebral hypoperfusion desp ite no evidence of ischemic change in the above MR study. These result s suggest that the slowly progressive neurological deficits are due to the primary underlying pathology rather than the secondary neuronal l oss as a result of frequent ischemic attacks. (C) 1997 Elsevier Scienc e B.V.