title: Cerebrospinal fluid alterations of the serotonin product, 5-hydroxyindolacetic acid, in neurological disorders.
abstract: Although patients with low cerebrospinal fluid (CSF) serotonin metabolite levels have been reported, inborn errors of the rate-limiting enzyme of serotonin synthesis (tryptophan hydroxylase, TPH) have not been described so far. In this study we aimed to evaluate CSF alterations of the serotonin metabolite 5-hydroxyindolacetic acid (5-HIAA) in patients with neurological disorders and to explore a possible TPH deficiency in some of them. A total of 606 patients (286 males, 320 females, mean age 4 years and 6 months, SD 5 years and 7 months) underwent CSF analysis of neurotransmitter metabolites by reverse phase high performance liquid chromatography. Results were compared with values established in a control population. Patients' medical records were reviewed to determine diagnosis and clinical features. A primary defect of biogenic amines was genetically investigated in indicated patients. Low 5-HIAA was seen in 19.3%. Of these, 22.2% showed inborn errors of metabolism (mitochondrial disorders being the most frequent at 10.2% of low 5-HIAA patients) and neurogenetic conditions. Other relatively frequent conditions were pontocerebellar hypoplasia (4.3%), Rett syndrome (4.3%), and among congenital nonetiologically determined conditions, epilepsy including epileptic encephalopathies (26.4%), leukodystrophies (6.8%), and neuropsychiatric disturbances (4.2%). Mutational analysis of the TPH2 gene, performed in five candidate patients, was negative. Although frequency of secondary alteration of 5-HIAA was relatively high in patients with neurological disorders, this finding was more frequently associated with some neurometabolic disorders, epileptic encephalopathies, and neuropsychiatric disturbances. No inborn errors of TPH were found. Due to serotonin's neurotrophic role and to ameliorate symptoms, a supplementary treatment with 5-hydroxytriptophan would seem advisable in these patients.
authors.affiliation: Neurology Department, Hospital Sant Joan de Deu, Barcelona, Spain.
authors.forename: Elisa
authors.initials: E
authors.lastname: De Grandis
authors.forename: Mercedes
authors.initials: M
authors.lastname: Serrano
authors.forename: Belén
authors.initials: B
authors.lastname: Pérez-Dueñas
authors.forename: Aida
authors.initials: A
authors.lastname: Ormazábal
authors.forename: Raquel
authors.initials: R
authors.lastname: Montero
authors.forename: Edvige
authors.initials: E
authors.lastname: Veneselli
authors.forename: Mercè
authors.initials: M
authors.lastname: Pineda
authors.forename: Verónica
authors.initials: V
authors.lastname: González
authors.forename: Francesc
authors.initials: F
authors.lastname: Sanmartí
authors.forename: Carmen
authors.initials: C
authors.lastname: Fons
authors.forename: Anna
authors.initials: A
authors.lastname: Sans
authors.forename: Bru
authors.initials: B
authors.lastname: Cormand
authors.forename: Luis
authors.initials: L
authors.lastname: Puelles
authors.forename: Antonia
authors.initials: A
authors.lastname: Alonso
authors.forename: Jaime
authors.initials: J
authors.lastname: Campistol
authors.forename: Rafael
authors.initials: R
authors.lastname: Artuch
authors.forename: Angels
authors.initials: A
authors.lastname: García-Cazorla
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D002658:Developmental Disabilities / Q000134:cerebrospinal fluid / Q000235:genetics; D005260:Female; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid* / Q000378:metabolism; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009422:Nervous System Diseases / Q000134:cerebrospinal fluid* / Q000453:epidemiology / Q000235:genetics / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism; D014365:Tryptophan Hydroxylase / Q000235:genetics
chemical_list: D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; C494784:TPH2 protein, human; D014365:Tryptophan Hydroxylase