title: Neurophysiological findings in a case of carbohydrate-deficient glycoprotein (CDG) syndrome type I with phosphomannomutase deficiency.
abstract: The carbohydrate-deficient glycoprotein (CDG) syndromes are multisystemic disorders involving the glycosylation pathway. The most common subtype is CDG syndrome type I (CDG I). In most CDG I patients a phosphomannomutase (PMM) deficiency has been recognized as the basic defect. We made a neurophysiological evaluation in an 8-year-old boy affected by CDG I with PMM deficiency. The evaluation included central and peripheral nervous system assessment [electroencephalogram (EEG), multimodal evoked potentials (MEP), somatosensory evoked potentials (SEP), visual evoked potentials (VEP), auditory brainstem response (ABR), electroretinogram (ERG) and motor and sensory nervous conduction velocity (NCV)]. We found a peculiar electrophysiological pattern characterized by slowly and mildly progressive motor NCV reduction; progressive impairment of ERG and VEP; slowing of background activity and sharp waves at the EEGs; late sensorineural abnormality of ABR; decreased amplitude and increased latency of SEP. To our knowledge this is the first report involving the neurophysiological aspects both at onset and during follow-up of a case of CDG I with proven PMM deficiency.
authors.affiliation: Department of Neurological Science and Neurorehabilitation, University of Genoa, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Veneselli
authors.forename: R
authors.initials: R
authors.lastname: Biancheri
authors.forename: M
authors.initials: M
authors.lastname: Di Rocco
authors.forename: S
authors.initials: S
authors.lastname: Tortorelli
mesh_terms: D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D018981:Congenital Disorders of Glycosylation / Q000175:diagnosis*; D004569:Electroencephalography; D004596:Electroretinography / Q000379:methods; D005071:Evoked Potentials / Q000502:physiology; D017809:Fatal Outcome; D006031:Glycosylation; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009431:Neural Conduction / Q000502:physiology; D010525:Peripheral Nerves / Q000503:physiopathology; D017875:Phosphotransferases (Phosphomutases) / Q000172:deficiency*; D011596:Psychomotor Disorders / Q000175:diagnosis; D012720:Severity of Illness Index
chemical_list: D017875:Phosphotransferases (Phosphomutases)