The International Working Group on Neurotransmitter related Disorders (iNTD): A worldwide research project focused on primary and secondary neurotransmitter disorders.
BACKGROUND
Neurotransmitters are chemical messengers that enable communication between the neurons in the synaptic cleft. Inborn errors of neurotransmitter biosynthesis, breakdown and transport are a group of very rare neurometabolic diseases resulting in neurological impairment at any age from newborn to adulthood.


RESULTS
The International Working Group on Neurotransmitter related Disorders (iNTD) is the first international network focusing on the study of primary and secondary neurotransmitter disorders. It was founded with the aim to foster exchange and improve knowledge in the field of these rare diseases. The newly established iNTD patient registry for neurotransmitter related diseases collects longitudinal data on the natural disease course, approach to diagnosis, therapeutic strategies, and quality of life of affected patients. The registry forms the evidence base for the development of consensus guidelines for patients with neurotransmitter related disorders.


CONCLUSIONS
The iNTD network and registry will improve knowledge and strengthen research capacities in the field of inborn neurotransmitter disorders. The evidence-based guidelines will facilitate standardized diagnostic procedures and treatment approaches.
Division of Child Neurology and Metabolic Diseases, University Children's Hospital Heidelberg, Germany.
Thomas
T
Opladen
Department of Child Neurology, Neurometabolic Unit, CIBERER-ISCIII, Hospital Sant Joan de Déu Barcelona, Spain.
Elisenda
E
Cortès-Saladelafont
Department of Pediatrics and Child Neuropsychiatry, Sapienza Università di Roma, Rome, Italy.
Mario
M
Mastrangelo
Division of Biochemical Diseases, BC, Childrens Hospital, Vancouver, Canada.
Gabriella
G
Horvath
First Department of Pediatrics, Pediatric Neurology Unit, Agia Sofia Hospital, National and Kapodistrian University of Athens, Athens, Greece.
Roser
R
Pons
Department of Pediatric Neurology, Reina Sofia University Hospital, Maimonides Biomedical Research Institute of Cordoba (IMIBIC), University of Cordoba, CIBERER-ISCIII, Cordoba, Spain.
Eduardo
E
Lopez-Laso
Department of Pediatric Neurology, Reina Sofia University Hospital, Maimonides Biomedical Research Institute of Cordoba (IMIBIC), University of Cordoba, CIBERER-ISCIII, Cordoba, Spain.
Joaquín A
JA
Fernández-Ramos
Dep. of Pediatrics, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic.
Tomas
T
Honzik
Department of Neurology, Washington University School of Medicine, St. Louis, USA.
Toni
T
Pearson
Department of Neurosciences, University of California San Diego, Division of Neurology Rady Children's Hospital, Rady Children's Institute Genomic Medicine, San Diego, USA.
Jennifer
J
Friedman
Department of Pediatrics I, Inherited Metabolic Disorders, Medical University of Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
Sabine
S
Scholl-Bürgi
Department of Neurology and Child Neurology, Radboudumc Nijmegen, Donders Institute of Brain Cognition and Behaviour, The Netherlands.
Tessa
T
Wassenberg
Division of Child Neurology and Metabolic Diseases, University Children's Hospital Heidelberg, Germany.
Sabine
S
Jung-Klawitter
Division of Child Neurology and Metabolic Diseases, University Children's Hospital Heidelberg, Germany.
Oya
O
Kuseyri
Division of Child Neurology and Metabolic Diseases, University Children's Hospital Heidelberg, Germany.
Kathrin
K
Jeltsch
Developmental Neurosciences, UCL- Institute of Child Health and Department of Neurology, Great Ormond Street Hospital for Children NHS Foundations Trust, London, United Kingdom.
Manju A
MA
Kurian
Department of Child Neurology, Neurometabolic Unit, CIBERER-ISCIII, Hospital Sant Joan de Déu Barcelona, Spain.
Àngels
À
Garcia-Cazorla
3-PGDH, 3-phosphoglycerat dehydrogenase; 3-PGH, 3-phosphoglycerat dehydrogenase; 3-PSP, 3-phosphoserine phosphatase; 5-MTHF, 5-methyltetrahydrofolate; AADC, aromatic l-amino acid decarboxylase; AR/ADGTPCH, autosomal recessive/dominant GTP-cyclohydrolase deficiency; BH4, tetrahydrobiopterin; DAT, dopamine transporter; DHFR, dihydrofolate reductase deficiency; DHPR, dihydropteridine reductase; Database; Dopamine; DßH, dopamine β-hydroxylase; FOLR1, folate receptor alpha; GABA; GABA, gamma aminobutyric acid; Glycine; Guideline; MAOA, monoamine oxidase A; NKH, nonketotic hyperglycinemia; NOS, nitric oxide synthase; Network; Neurotransmitter; PAH, phenylalanine hydroxylase; PSAT, phosphoserine aminotransferase; PTPS, 6-pyruvoyl-tetrahydropterin synthase; Patient registry; SR, sepiapterin reductase; SSADH, succinic semialdehyde dehydrogenase; Serine; Serotonin; TH, tyrosine hydroxylase; TPH, tryptophan hydroxylase; VMAT, vesicular monoamine transporter