title: Carnitine-acylcarnitine translocase deficiency: experience with four cases in Spain and review of the literature.
abstract: BACKGROUND
  Carnitine-acylcarnitine translocase (CACT) deficiency is a rare autosomal recessive disease in the mitochondrial transport of long-chain fatty acids. Despite early diagnosis and treatment, the disease still has a high mortality rate.
  
  
  METHODS
  Clinical symptoms, long-term follow-up, and biochemical and molecular results of four cases are described and compared with the reviewed literature data of 55 cases.
  
  
  RESULTS
  Two cases with neonatal onset, carrying in homozygosity the novel variant sequences p.Gly20Asp (c.59G>A) and p.Arg179Gly (c.536A>G), died during an intercurrent infectious process in the first year of life despite adequate dietetic treatment (frequent feeding, high-carbohydrate/low-fat diet, MCT, carnitine). The other two cases, one with infantile onset and the other diagnosed in the newborn period after a previous affected sibling, show excellent development at 4 and 16 years of age under treatment. The review shows that the most frequent presenting symptoms of CACT deficiency are hypoketotic hypoglycemia, hyperammonemia, hepatomegaly, cardiomyopathy and/or arrhythmia, and respiratory distress. The onset of symptoms is predominantly neonatal in 82% and infantile in 18%. The mortality rate is high (65%), most in the first year of life due to myocardiopathy or sudden death. Outcomes seem to correlate better with the absence of cardiac disease and with a higher long-chain fatty acid oxidation rate in cultured fibroblasts than with residual enzyme activity.
  
  
  CONCLUSIONS
  Diagnosis before the occurrence of clinical symptoms by tandem MS-MS and very early therapeutic intervention together with good dietary compliance could lead to a better prognosis, especially in milder clinical cases.
authors.affiliation: Unit of Metabolopathies, Hospital la Fe, Bulevar sur s/n, 46021, Valencia, Spain, Vitoria_isi@gva.es.
authors.forename: Isidro
authors.initials: I
authors.lastname: Vitoria
authors.forename: Elena
authors.initials: E
authors.lastname: Martín-Hernández
authors.forename: Luis
authors.initials: L
authors.lastname: Peña-Quintana
authors.forename: María
authors.initials: M
authors.lastname: Bueno
authors.forename: Pilar
authors.initials: P
authors.lastname: Quijada-Fraile
authors.forename: Jaime
authors.initials: J
authors.lastname: Dalmau
authors.forename: Sofia
authors.initials: S
authors.lastname: Molina-Marrero
authors.forename: Belén
authors.initials: B
authors.lastname: Pérez
authors.forename: Begoña
authors.initials: B
authors.lastname: Merinero