title: [Thyroid dysfunction after haematopoietic stem cell transplantation during childhood].
abstract: To evaluate the percentage and risk factors of thyroid dysfunction in 79 children who underwent bone marrow transplantation in a single centre.
  
  
  METHODS
  The mean age of the cohort was 6.8 and mean follow-up 5.5 years. The 79 patients were divided in two groups according to the pretransplant conditioning regimen: fractionated total body irradiation (TBI)(N=54), chemotherapy with Busulphan (N=25). Thyroid function was evaluated by thyroid-stimulating hormone (TSH) and free thyroxine (fT4) tests. Overt hypothyroidism was defined by low fT4 blood levels and TSH > 4 mU/l, and compensated hypothyroidism by normal fT4 index and TSH >4 mU/L.
  
  
  RESULTS
  The six-year probability of hypothyroidism was 36 +/-6% for the whole group of 79 patients, 49 +/-8% after TBI and 9 +/-6% in the Busulphan group (P <0.001). Neither gender, nor primary disease, nor presence of graft versus host disease were found to be statistically significant for occurrence of hypothyroidism in the TBI group. However, a younger age seemed to influence statistically the 6-year probability of hypothyroidism in the TBI group: 59 +/-9% if age <7.7 years versus 34 +/-13% if age >7.7 years (P =0.02).
  
  
  CONCLUSIONS
  A careful follow-up of thyroid function is recommended even without TBI conditioning regimen. Young age as a potential risk factor of hypothyroidism has never been described and needs to be studied in a larger cohort.
authors.affiliation: Service hématologie pédiatrique du professeur Michel, hôpital Timone-Enfants, 264, rue Saint-Pierre, 13385 Marseille cedex 05, France. Catherine.Curtillet@mail.ap-hm.fr
authors.forename: C
authors.initials: C
authors.lastname: Curtillet
authors.forename: P
authors.initials: P
authors.lastname: Cuadras
authors.forename: E
authors.initials: E
authors.lastname: Dore
authors.forename: H
authors.initials: H
authors.lastname: Chambost
authors.forename: I
authors.initials: I
authors.lastname: Thuret
authors.forename: G
authors.initials: G
authors.lastname: Michel
mesh_terms: D000293:Adolescent; D000367:Age Factors; D016026:Bone Marrow Transplantation / Q000009:adverse effects*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000209:etiology*; D007223:Infant; D008297:Male; D009369:Neoplasms / Q000628:therapy; D012307:Risk Factors; D014916:Whole-Body Irradiation / Q000009:adverse effects