European Journal of Pediatrics

, Volume 155, Supplement 1, pp S64–S68 | Cite as

Studies of multimodal evoked potentialsin treated phenylketonuria: the pattern of vulnerability

  • A. C. Ludolph
  • U. Vetter
  • K. Ullrich


We performed studies of multimodal evoked potentials and peripheral sensory and motor nerve conductions in 33 early and 6 late treated patients with phenylketonuria. The studies revealed the following picture:
  1. 1.

    In 27% of early treated patients latencies of visual evoked potentials were increased. The cause for these changes is unknown.

  2. 2.

    Nerve conduction studies showed the presence of a minor sensory neuropathy which in rare cases may also affect peripheral motor nerves. This neuropathy did not have features of a central-peripheral distal axonopathy which argues against a toxic/nutritional causation.

  3. 3.

    Deficits in the central sensory, motor, and auditory pathways were present, but rare in early treated patients.


If the results of electrophysiological studies reported by different groups are compared, the emerging picture is very similar and the majority of the — minor — differences is likely to be explained by technical aspects.

Key words

Hyperphenylaninaemia Phenylketonuria Evoked potentials Metabolic disorders Dopamine 





visual evoked potential


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Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  • A. C. Ludolph
    • 1
  • U. Vetter
    • 2
  • K. Ullrich
    • 3
  1. 1.Department of NeurologyHumboldt UniversityBerlinGermany
  2. 2.Department of PaediatricsHumboldt UniversityBerlinGermany
  3. 3.Department of PaediatricsUniversity of MünsterMünsterGermany

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