title: [Primary carnitine deficiency in 17 patients: diagnosis, treatment and follow up].
abstract: OBJECTIVE
  Many children were found to have low free carnitine level in blood by tandem mass spectrometry technology. In some of the cases the problems occurred secondary to malnutrition, organic acidemia and other fatty acid oxidation metabolic diseases, and some of cases had primary carnitine deficiency (PCD). In the present article, we discuss the diagnosis of PCD and evaluate the efficacy of carnitine in the treatment of PCD.
  
  
  METHODS
  We measured the free carnitine (C0) and acylcarnitine levels in the blood of 270 000 neonates from newborns screening program and 12 000 children with suspected clinical inherited metabolic diseases by tandem mass spectrometry. The mutations of carnitine transporter protein were tested to the children with low C0 level and the diagnosis was made. The children with PCD were treated with 100 - 300 mg/kg of carnitine.
  
  
  RESULTS
  Seventeen children were diagnosed with PCD, 6 from newborn screening program and 11 from clinical patients. Mutations were found in all of them. The average C0 level [(2.9 ± 2.0) µmol/L] in patients was lower than the reference value (10 µmol/L), along with decreased level of different acylcarnitines. The clinical manifestations were diverse. For the 6 patients from newborn screening, 4 were asymptomatic, 1 showed hypoglycaemia and 1 showed movement intolerance from 2 years of age. For the 11 clinical patients, 8 showed hepatomegaly, 7 showed myasthenia, 6 showed cardiomyopathy, 1 showed chronic abdominal pain, and 1 showed restlessness and learning difficulty. Among these patients, 14 cases were treated with carnitine. Their clinical symptoms disappeared 1 to 3 months later. The C0 level in the blood rose to normal, with the average from (4.0 ± 2.7) µmol/L to (20.6 ± 8.3) µmol/L (P < 0.01). However, the level was still lower than the average level of healthy children [(27.1 ± 4.5) µmol/L, P < 0.01].
  
  
  CONCLUSIONS
  Seventeen patients were diagnosed with PCD by the test levels of free carnitine and acylcarnitines in blood with tandem mass spectrometry, and gene mutation test. Large dose of carnitine had a good effect in treatment of the PCD patients.
authors.affiliation: Department of Pediatric Endocrinologic and Genetic Metabolism, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Lian-shu
authors.initials: LS
authors.lastname: Han
authors.forename: Jun
authors.initials: J
authors.lastname: Ye
authors.forename: Wen-juan
authors.initials: WJ
authors.lastname: Qiu
authors.forename: Hui-wen
authors.initials: HW
authors.lastname: Zhang
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Wen-jun
authors.initials: WJ
authors.lastname: Ji
authors.forename: Xiao-lan
authors.initials: XL
authors.lastname: Gao
authors.forename: Xiao-yan
authors.initials: XY
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Jin
authors.forename: Xue-fan
authors.initials: XF
authors.lastname: Gu
mesh_terms: D009202:Cardiomyopathies / Q000175:diagnosis* / Q000188:drug therapy* / Q000235:genetics; D002331:Carnitine / Q000031:analogs & derivatives* / Q000097:blood* / Q000172:deficiency / Q000235:genetics; D002675:Child, Preschool; D004252:DNA Mutational Analysis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D022124:Hyperammonemia / Q000175:diagnosis* / Q000188:drug therapy* / Q000235:genetics; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009135:Muscular Diseases / Q000175:diagnosis* / Q000188:drug therapy* / Q000235:genetics; D009154:Mutation; D015997:Neonatal Screening / Q000379:methods; D027701:Organic Cation Transport Proteins / Q000172:deficiency / Q000235:genetics; D012016:Reference Values; D053719:Tandem Mass Spectrometry
chemical_list: D027701:Organic Cation Transport Proteins; D002331:Carnitine