A new case of hyperargininaemia: neurological and biochemical findings prior to and during dietary treatment.

We present clinical and biochemical data on a further patient with hyperargininaemia and the results of neurophysiological tests both before and during dietary treatment with an essential amino acid mixture. With normalisation of plasma arginine concentrations, neurological functions improved and brain stem auditory evoked potentials normalized suggesting a partially reversible central conduction disorder. Neuroradiological findings included cerebral cortical atrophy on computed tomography scan and patchy abnormal myelination on magnetic resonance imaging (MRI). The typical clinical picture is discussed with reference to published therapeutical trials.