title: Maternal vitamin B12 deficiency detected in expanded newborn screening.
abstract: OBJECTIVE
  Besides the inherited form, vitamin B(12) deficiency may be due to diet restrictions or abnormal absorption. The spread of newborn screening programs worldwide has pointed out that non-inherited conditions are mainly secondary to a maternal deficiency. The aim of our work was to study seven cases of acquired vitamin B12 deficiency detected during our newborn screening project. Moreover, we aimed to evaluate vitamin B(12) and related biochemical parameters status on delivering female to verify the consequences on newborns of eventually altered parameters.
  
  
  METHODS
  35,000 newborns were screened; those showing altered propionyl carnitine (C3) underwent second-tier test for methylmalonic acid (MMA) on dried blood spot (DBS). Subsequently, newborns positive to the presence of MMA on DBS and their respective mothers underwent further tests: serum vitamin B(12), holo-transcobalamin (Holo-TC), folate and homocysteine; newborns were also tested for urinary MMA content. A control study was conducted on 203 females that were tested for the same parameters when admitted to hospital for delivery.
  
  
  RESULTS
  Approximately 10% of the examined newborns showed altered C3. Among these, seven cases of acquired vitamin B(12) deficiency were identified (70% of the MMA-positive cases). Moreover, our data show a high frequency of vitamin B(12) deficiency in delivering female (approximately 48% of examined pregnants).
  
  
  CONCLUSIONS
  We suggest to monitor vitamin B(12) and Holo-TC until delivery and to reconsider the reference interval of vitamin B(12) for a better identification of cases at risk. Finally, newborns from mothers with low or borderline levels of vitamin B(12) should undergo second-tier test for MMA; in the presence of MMA they should be supplemented with vitamin B(12) to prevent adverse effects related to vitamin B(12) deficiency.
authors.affiliation: CEINGE Biotecnologie Avanzate Scarl, Napoli, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Scolamiero
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy.
authors.forename: Guglielmo Rosario Domenico
authors.initials: GR
authors.lastname: Villani
authors.affiliation: CEINGE Biotecnologie Avanzate Scarl, Napoli, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Ingenito
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Pecce
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Albano
authors.affiliation: CEINGE Biotecnologie Avanzate Scarl, Napoli, Italy.
authors.forename: Marianna
authors.initials: M
authors.lastname: Caterino
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: di Girolamo
authors.affiliation: T.I.N.-P.O. Umberto I Nocera Inferiore, Salerno, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Di Stefano
authors.affiliation: T.I.N.-P.O. Umberto I Nocera Inferiore, Salerno, Italy.
authors.forename: Ignazio
authors.initials: I
authors.lastname: Franzese
authors.affiliation: Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Gallo
authors.affiliation: CEINGE Biotecnologie Avanzate Scarl, Napoli, Italy; Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli "Federico II", Napoli, Italy. Electronic address: margherita.ruoppolo@unina.it.
authors.forename: Margherita
authors.initials: M
authors.lastname: Ruoppolo
mesh_terms: D002331:Carnitine / Q000031:analogs & derivatives / Q000097:blood; D005260:Female; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D008764:Methylmalonic Acid / Q000097:blood / Q000652:urine; D015997:Neonatal Screening / Q000379:methods*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000175:diagnosis*; D014155:Transcobalamins / Q000378:metabolism; D014805:Vitamin B 12 / Q000097:blood / Q000378:metabolism*; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000175:diagnosis*
chemical_list: D014155:Transcobalamins; D006710:Homocysteine; C003223:propionylcarnitine; D008764:Methylmalonic Acid; D005492:Folic Acid; D014805:Vitamin B 12; D002331:Carnitine
keywords: Methylmalonic acid; Newborn screening; Tandem mass spectrometry; Vitamin B(12) deficiency