title: [Autosomal recessive GTPCH 1 deficiency: the importance of the analysis of neurotransmitters in cerebrospinal fluid].
abstract: BACKGROUND
  A deficiency of the enzyme guanosine triphosphate cyclohydrolase I (GTPCH 1) causes a reduction in the synthesis of tetrahydrobiopterin (BH4), a cofactor that is essential in the synthesis of tyrosine, dopamine and serotonin. It is an infrequent disease that produces psychomotor delay or regression and movement disorders, although treatment can improve or even correct the clinical signs and symptoms.
  
  
  METHODS
  We report the case of a girl with autosomal recessive GTPCH deficiency, who was diagnosed at 14 months by means of an analysis of the cerebrospinal fluid with pterin, HVA and 5-HIAA deficiency, and positive phenylalanine overload test and genetic study. The clinical features began at the age of 5 months with intermittent upper limb and brain tremors, both at rest and intentional, that disappeared after a month. Psychomotor development was normal, mild axial hypotonia being found in the examination while the complementary tests that were performed were normal. The patient later presented psychomotor regression with loss of head control, diminished active movements, difficulty in bimanual manipulation, hypomimia and severe global hypotonia, which was the reason for the study of a progressive encephalopathy. Following the diagnosis of GTPCH deficiency, replacement therapy was established with levodopa/carbidopa, OH tryptophan and BH4, with excellent progress made in motor and cognitive functioning. Today, the patient is 5 years old, has an adequate psychomotor development for her age, is in the third year of preschool education and has caught up with the level of the rest of her classmates.
  
  
  CONCLUSIONS
  In this case attention must be drawn to the extremely satisfactory motor and cognitive improvement of the patient after starting replacement therapy, as in many cases the cognitive level is usually affected on a permanent basis.
authors.affiliation: Hospital Regional Universitario de Malaga, Malaga, Espana.
authors.forename: E E
authors.initials: EE
authors.lastname: Moreno-Medinilla
authors.affiliation: Hospital Regional Universitario de Malaga, Malaga, Espana.
authors.forename: M D
authors.initials: MD
authors.lastname: Mora-Ramirez
authors.affiliation: Hospital Regional Universitario de Malaga, Malaga, Espana.
authors.forename: R
authors.initials: R
authors.lastname: Calvo-Medina
authors.affiliation: Hospital Regional Universitario de Malaga, Malaga, Espana.
authors.forename: J
authors.initials: J
authors.lastname: Martinez-Anton
mesh_terms: D001708:Biopterins / Q000096:biosynthesis*; D005260:Female; D006136:GTP Cyclohydrolase / Q000172:deficiency*; D006801:Humans; D007223:Infant; D018377:Neurotransmitter Agents / Q000134:cerebrospinal fluid*; D010649:Phenylalanine; D011596:Psychomotor Disorders / Q000175:diagnosis*
chemical_list: D018377:Neurotransmitter Agents; D001708:Biopterins; D010649:Phenylalanine; D006136:GTP Cyclohydrolase