title: Cerebral folate deficiency and leukoencephalopathy caused by a mitochondrial DNA deletion.
abstract: OBJECTIVE
  Our aim was to describe a child with an incomplete form of Kearns-Sayre syndrome who presented profound cerebrospinal fluid (CSF) folate deficiency and his response to folinic acid supplementation
  
  
  METHODS
  CSF 5-methyltetrahydrofolate was analyzed by HPLC with fluorescence detection and mitochondrial DNA deletions by southern blot hybridization.
  
  
  RESULTS
  Cranial magnetic resonance imaging showed a leukoencephalopathy. Profound CSF 5-methyltetrahydrofolate deficiency was observed with normal blood folate values and decreased CSF/serum folate ratio, suggesting a transport defect across the blood-brain barrier. Folinic acid treatment was established, and after 1 year clinical response to folinic supplementation was remarkable, with almost normal white matter image.
  
  
  CONCLUSIONS
  The clinical response after folinic therapy highlights the need for the study of cerebral folate deficiency in patients with mitochondrial disorders and white matter lesions.
authors.affiliation: Servicios de Neuropediatría, Bioquímica y Endocrinología, Hospital Sant Joan de Déu, Clínic, Barcelona, Spain. pineda@hsjdbcn.org
authors.forename: Merce
authors.initials: M
authors.lastname: Pineda
authors.forename: Aida
authors.initials: A
authors.lastname: Ormazabal
authors.forename: Esther
authors.initials: E
authors.lastname: López-Gallardo
authors.forename: Andres
authors.initials: A
authors.lastname: Nascimento
authors.forename: Abelardo
authors.initials: A
authors.lastname: Solano
authors.forename: Maria D
authors.initials: MD
authors.lastname: Herrero
authors.forename: Maria A
authors.initials: MA
authors.lastname: Vilaseca
authors.forename: Paz
authors.initials: P
authors.lastname: Briones
authors.forename: Lourdes
authors.initials: L
authors.lastname: Ibáñez
authors.forename: Julio
authors.initials: J
authors.lastname: Montoya
authors.forename: Rafael
authors.initials: R
authors.lastname: Artuch
mesh_terms: D001923:Brain Chemistry / Q000235:genetics; D002648:Child; D004252:DNA Mutational Analysis / Q000379:methods; D004272:DNA, Mitochondrial / Q000235:genetics*; D005492:Folic Acid / Q000097:blood / Q000134:cerebrospinal fluid; D005494:Folic Acid Deficiency / Q000150:complications / Q000235:genetics* / Q000473:pathology; D017353:Gene Deletion; D006801:Humans; D007625:Kearns-Sayre Syndrome / Q000134:cerebrospinal fluid / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009132:Muscles / Q000378:metabolism
chemical_list: D004272:DNA, Mitochondrial; D005492:Folic Acid