[Inborn errors of neurotransmitters in neuropaediatrics].
OBJECTIVE
The aim of this work is to describe the clinical, biochemical and genetic characteristics of neurotransmitter diseases at the paediatric age, together with possible forms of treatment. We also sought to determine the diagnostic methodology of these disorders (collection and analysis of samples).


METHODS
These diseases essentially consist of a deficit of biogenic amines and alterations in GABA metabolism (gamma-aminobutyric acid). Disorders affecting the neurotransmission of biogenic amines often present in the form of hypokinesia, trunk hypotonia with increased limb tone, oculogyric crises, ptosis, faulty temperature regulation or abnormal movements. Defects in GABA metabolism give rise to epileptic encephalopathies and unspecific mental retardation, sometimes associated to signs of cerebellar dysfunction, convulsions and alterations in neuroimaging studies. Overall incidence of these diseases is low but they are unquestionably under-diagnosed, since they cannot be detected by conventional studies in plasma and urine, and require extraction and directed analysis of cerebrospinal fluid (CSF) for their detection. Additionally, the CSF study must be carried out in specific standardised conditions. Segawa's disease, or dopa-responsive dystonia, responds extremely well to therapy, whereas the other entities respond in varying ways to the different therapeutic alternatives.


CONCLUSIONS
It is important for the paediatrician to know about these entities as a group of treatable neurometabolic diseases. Moreover, their detection would allow prenatal diagnosis in the vast majority of cases.
García-Cazorla
A
A
Hospital Sant Joan de Déu, Esplugues de Llobregat, Barcelona, Spain. agarcia@hsjdbcn.org
Ormazábal
A
A
Artuch
R
R
Pérez-Dueñas
B
B
López-Casas
J
J
Fernández-Alvarez
E
E
Campistol
J
J
D000293:Adolescent; D017668:Age of Onset; D002648:Child; D002653:Child Behavior Disorders / Q000235:genetics; D002675:Child, Preschool; D004827:Epilepsy / Q000235:genetics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000235:genetics; D008297:Male; D008661:Metabolism, Inborn Errors / Q000134:cerebrospinal fluid / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D009419:Nerve Tissue Proteins / Q000172:deficiency / Q000235:genetics; D009422:Nervous System Diseases / Q000134:cerebrospinal fluid / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism / Q000628:therapy; D009462:Neurology; D018377:Neurotransmitter Agents / Q000378:metabolism*; D010372:Pediatrics
D009419:Nerve Tissue Proteins; D018377:Neurotransmitter Agents