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Original article

Vol. 144 No. 5152 (2014)

Integration of adult patients with phenylketonuria into professional life: Long-term follow-up of 27 patients in a single centre in Switzerland

  • Sabrina Pers
  • Matthias Gautschi
  • Jean-Marc Nuoffer
  • Hanspeter Schwarz
  • Emanuel Christ
Cite this as:
Swiss Med Wkly. 2014;144:w14074


BACKGROUND: Neonatal screening and treatment of phenylketonuria (PKU) prevent the development of neurocognitive impairment. The degree of dysfunction may be related to metabolic control and responsible for a hampered school career.

METHODS: This was a retrospective study from a single metabolic unit of a Swiss University Hospital. The time point of diagnosis and all Phenylalanin (Phe) concentrations during the follow-up were recorded. The primary outcome was integration into professional life defined as no professional studies versus accomplished apprenticeship versus high school diploma/university. Phe levels were correlated with professional outcome. The control group consisted of the patients’ healthy parents and siblings.

RESULTS: A total of 27 patients (13 females, 14 males) were included in the study. The mean (SD) follow-up period was 25.1 (7.6) years. The control group consisted of 57 subjects. Overall, 23 patients were diagnosed by neonatal screening, and 4 patients were diagnosed later. All 4 were in the non-professional study group. Compared with the controls there were significantly more patients in the non-professional study group (26% vs 9%, p <0.05) and significantly less in the accomplished apprenticeship group (59% vs 82%; p <0.04). After exclusion of the patients with late diagnosis no significant differences were found with regard to the professional integration between patients and controls. Significant differences in Phe-levels between the three groups could be documented between 2–10 years of age with the highest levels in the non-professional study followed by the accomplished apprenticeship and the high school diploma group (p <0.01).

CONCLUSION: Patients who are diagnosed by neonatal screening and are consequently cared for are able to accomplish an apprenticeship or a high school diploma.

Reference to electronic database: Phenylketonuria MIM # 261600


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