title: Unusual case of thiamine responsive megaloblastic anemia.
abstract: BACKGROUND
  Thiamine-responsive megaloblastic anemia syndrome is a rare autosomal recessive disorder defined by the occurrence of megaloblastic anemia, diabetes mellitus, and neurosensoriel deafness, responding in varying degrees to thiamine treatment.
  
  
  OBJECTIVE
  Report an unusual case of this rare disorder
  
  
  METHODS
  We report the case of a four-year-old boy who presented unusual features of thiamine-responsive megaloblastic anemia. In addition to the typical triad of the syndrome, he presented leuconeutropenia, hepatosplenomegalia, cardiac abnormalities including absent P waves, mitral and tricuspid insufficiency, retinitis pigmentosa, nystagmus, developmental delay and a brain Magnetic resonance imaging ischemic lesion. Lactate levels in serum and the lactate/pyruvate ratio were increased. The mitochondrial mutation m.3243A > G located in MTTL1 gene encoding for transfer RNA leucine (tRNALeu(UUR)) was not found. Treatment with thiamine resulted in normalisation of the haemoglobin level, white cell count, and glucose and lactate levels. On three years follow up, the patient did not need insulinotherapy.
  
  
  CONCLUSIONS
  These data sign the crucial role that thiamine plays for many cells and tissues and its importance in the activity of the respiratory chain.
authors.affiliation: Department of Pediatrics B, Children's Hospital of Tunis.
authors.forename: Faten
authors.initials: F
authors.lastname: Tinsa
authors.forename: Saadia
authors.initials: S
authors.lastname: Ben Amor
authors.forename: Naziha
authors.initials: N
authors.lastname: Kaabachi
authors.forename: Mehdi
authors.initials: M
authors.lastname: Ben Lasouad
authors.forename: Khadija
authors.initials: K
authors.lastname: Boussetta
authors.forename: Souad
authors.initials: S
authors.lastname: Bousnina
mesh_terms: D000749:Anemia, Megaloblastic / Q000150:complications / Q000188:drug therapy* / Q000235:genetics; D001786:Blood Glucose / Q000187:drug effects; D002675:Child, Preschool; D003241:Consanguinity; D006454:Hemoglobins / Q000187:drug effects; D006801:Humans; D007773:Lactates / Q000097:blood; D007962:Leukocytes / Q000187:drug effects; D008297:Male; D013577:Syndrome; D013831:Thiamine / Q000627:therapeutic use*; D016896:Treatment Outcome; D014803:Vitamin B Complex / Q000627:therapeutic use*
chemical_list: D001786:Blood Glucose; D006454:Hemoglobins; D007773:Lactates; D014803:Vitamin B Complex; D013831:Thiamine