AUTHOR=Santoro Jonathan D. , Patel Lina , Kammeyer Ryan , Filipink Robyn A. , Gombolay Grace Y. , Cardinale Kathleen M. , Real de Asua Diego , Zaman Shahid , Santoro Stephanie L. , Marzouk Sammer M. , Khoshnood Mellad , Vogel Benjamin N. , Tanna Runi , Pagarkar Dania , Dhanani Sofia , Ortega Maria del Carmen , Partridge Rebecca , Stanley Maria A. , Sanders Jessica S. , Christy Alison , Sannar Elise M. , Brown Ruth , McCormick Andrew A. , Van Mater Heather , Franklin Cathy , Worley Gordon , Quinn Eileen A. , Capone George T. , Chicoine Brian , Skotko Brian G. , Rafii Michael S. TITLE=Assessment and Diagnosis of Down Syndrome Regression Disorder: International Expert Consensus JOURNAL=Frontiers in Neurology VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.940175 DOI=10.3389/fneur.2022.940175 ISSN=1664-2295 ABSTRACT=Objective

To develop standardization for nomenclature, diagnostic work up and diagnostic criteria for cases of neurocognitive regression in Down syndrome.

Background

There are no consensus criteria for the evaluation or diagnosis of neurocognitive regression in persons with Down syndrome. As such, previously published data on this condition is relegated to smaller case series with heterogenous data sets. Lack of standardized assessment tools has slowed research in this clinical area.

Methods

The authors performed a two-round traditional Delphi method survey of an international group of clinicians with experience in treating Down syndrome to develop a standardized approach to clinical care and research in this area. Thirty-eight potential panelists who had either previously published on neurocognitive regression in Down syndrome or were involved in national or international working groups on this condition were invited to participate. In total, 27 panelists (71%) represented nine medical specialties and six different countries reached agreement on preliminary standards in this disease area. Moderators developed a proposed nomenclature, diagnostic work up and diagnostic criteria based on previously published reports of regression in persons with Down syndrome.

Results

During the first round of survey, agreement on nomenclature for the condition was reached with 78% of panelists agreeing to use the term Down Syndrome Regression Disorder (DSRD). Agreement on diagnostic work up and diagnostic criteria was not reach on the first round due to low agreement amongst panelists with regards to the need for neurodiagnostic testing. Following incorporation of panelist feedback, diagnostic criteria were agreed upon (96% agreement on neuroimaging, 100% agreement on bloodwork, 88% agreement on lumbar puncture, 100% agreement on urine studies, and 96% agreement on “other” studies) as were diagnostic criteria (96% agreement).

Conclusions

The authors present international consensus agreement on the nomenclature, diagnostic work up, and diagnostic criteria for DSRD, providing an initial practical framework that can advance both research and clinical practices for this condition.