title: Biotin and carnitine profiles in preterm infants in Japan.
abstract: BACKGROUND
  Biotin plays an important role as a covalently bound coenzyme for carboxylases. Carnitine is essential in β-oxidation to transport long-chain fatty acids across the inner mitochondrial membrane. The present study was conducted to assess the risk of biotin and carnitine deficiencies in preterm infants who received enteral feeding with maternal milk and/or standard infant formula made in Japan.
  
  
  METHODS
  Forty-six infants were enrolled in the study. Urine and serum samples and dried blood spots were collected at 1 week and 1 month of age. Additionally, samples were collected at 40 and 44 weeks post-menstrual age (PMA) in preterm infants. Free carnitine and C5-OH acylcarnitine, which consist of 3-hydroxyisovalerylcarnitine as a major isomer, were measured in serum samples and dried blood spots using tandem mass spectrometry. Urine 3-hydroxyisovaleric acid (3-HIVA) was measured using gas chromatography/mass spectrometry.
  
  
  RESULTS
  The free carnitine levels in preterm infants were significantly lower than those in term infants, but increased with PMA in serum samples and dried blood spots. C5-OH acylcarnitine and urinary 3-HIVA levels, which were very low in term infants, were increased with PMA in preterm infants.
  
  
  CONCLUSIONS
  The present results may indicate chronic biotin deficiency in preterm infants fed maternal milk and/or standard infant formula. Analyses of carnitine profiles of dried blood spots and urine 3-HIVA are relatively non-invasive and useful for the early detection of biotin deficiency in preterm infants.
authors: Department of Pediatrics, University of Fukui, Fukui, Japan. shu@u-fukui.ac.jp
authors: Shuko
authors: S
authors: Tokuriki
authors: Hisako
authors: H
authors: Hayashi
authors: Takashi
authors: T
authors: Okuno
authors: Kikuko
authors: K
authors: Yoshioka
authors: Shintaro
authors: S
authors: Okazaki
authors: Akiko
authors: A
authors: Kawakita
authors: Genrei
authors: G
authors: Ohta
authors: Ikue
authors: I
authors: Hata
authors: Yosuke
authors: Y
authors: Shigematsu
authors: Yusei
authors: Y
authors: Ohshima
mesh_terms: D001710:Biotin / Q000097:blood* / Q000172:deficiency*; D002331:Carnitine / Q000097:blood* / Q000172:deficiency*; D059788:Dried Blood Spot Testing; D004750:Enteral Nutrition; D005260:Female; D005865:Gestational Age; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000097:blood*; D007363:Intensive Care Units, Neonatal; D007564:Japan; D008297:Male; D008895:Milk, Human; D012016:Reference Values
chemical_list: D001710:Biotin; D002331:Carnitine