Irish Journal of Medical Science (1971 -)

, Volume 185, Issue 1, pp 241–248 | Cite as

Unexplained developmental delay/learning disability: guidelines for best practice protocol for first line assessment and genetic/metabolic/radiological investigations

  • J. J. O’ByrneEmail author
  • S. A. Lynch
  • E. P. Treacy
  • M. D. King
  • D. R. Betts
  • P. D. Mayne
  • F. Sharif
Original Article



Investigation of patients, particularly children, with unexplained global developmental delay (GDD)/learning disability (LD) has been challenging due to a lack of clear guidance from specialised centres. Limited knowledge of rare diseases and a poor understanding of the purpose or limitations of appropriate investigations have been some of the principal reasons for this difficulty.


A guideline development group was formed to recommend on appropriate, first line metabolic, genetic and radiological investigations for children and adults with unexplained GDD/ID.

Methods and recommendations

A comprehensive literature search was conducted, evaluated and reviewed by the guideline committee and a best practice protocol for first line assessment and genetic, metabolic and radiological investigations was decided upon after considering diagnostic yield, practicality, treatability and costs.


It is hoped that these recommendations will become national guidelines for the first line metabolic, genetic and radiological investigation of patients presenting with unexplained GDD/ID.


Guidelines Global developmental delay Learning disability First line investigations 



This guideline has been developed in collaboration with the following contributions:

Prof. A.J. Green, Dr. D.E. Barton, Dr. M. Sweeney: contributions from The Department of Clinical Genetics, Our Lady’s Children’s Hospital, Crumlin, Dublin 12, Ireland.

Dr. A.A. Monavari, Dr. E. Crushell, Dr. J. Hughes, Dr. I. Knerr: contributions from The National Centre for Inherited Metabolic Disorders, Temple Street Children’s University Hospital, Dublin 1, Ireland

Ms. P. Fitzsimons: contributions from The Department of Biochemistry, Temple Street Children’s University Hospital, Dublin 1, Ireland.

Dr. S. Macken: contributions from The Department of Developmental Paediatrics, Temple Street Children’s University Hospital, Dublin 1, Ireland.


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Copyright information

© European Union 2015

Authors and Affiliations

  • J. J. O’Byrne
    • 1
    Email author
  • S. A. Lynch
    • 1
  • E. P. Treacy
    • 2
  • M. D. King
    • 3
  • D. R. Betts
    • 1
  • P. D. Mayne
    • 4
  • F. Sharif
    • 5
  1. 1.Department of Clinical GeneticsOur Lady’s Children’s HospitalDublin 12Ireland
  2. 2.National Centre for Inherited Metabolic DisordersTemple Street Children’s University HospitalDublin 1Ireland
  3. 3.Department of NeurologyTemple Street Children’s University HospitalDublin 1Ireland
  4. 4.Department of BiochemistryTemple Street Children’s University HospitalDublin 1Ireland
  5. 5.Department of PaediatricsMidland Regional HospitalMullingarIreland

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