TY - JOUR
T1 - Levothyroxine requirement in congenital hypothyroidism
T2 - a 12-year longitudinal study
AU - Delvecchio, Maurizio
AU - Salerno, Mariacarolina
AU - Vigone, Maria Cristina
AU - Wasniewska, Malgorzata
AU - Popolo, Pietro Pio
AU - Lapolla, Rosa
AU - Mussa, Alessandro
AU - Tronconi, Giulia Maria
AU - D’Acunzo, Ida
AU - Di Mase, Raffaella
AU - Falcone, Rosa Maria
AU - Corrias, Andrea
AU - De Luca, Filippo
AU - Weber, Giovanna
AU - Cavallo, Luciano
AU - Faienza, Maria Felicia
PY - 2015/12/1
Y1 - 2015/12/1
N2 - The aim of the replacement therapy with levothyroxine in congenital hypothyroidism (CH) is to correct hypothyroidism and ensure normal growth and neuropsychological development. Few data are available about the appropriate dose during childhood and early adolescence; therefore, we performed a multicenter observational study in a large population of patients with CH to assess the required levothyroxine dose to obtain euthyroidism. We recruited 216 patients with permanent CH classified into three groups (agenesia, ectopia, and in situ gland) on the basis of the thyroid imaging. The levothyroxine dose was recorded at 6 and 12 months and then yearly until 12 years of age. The daily levothyroxine requirement progressively decreased during the follow-up, irrespective of etiology. It was significantly lower in patients with in situ gland than in patients with athyreosis during the entire study period and with ectopic gland from the age of 1 year. The levothyroxine requirement at 6 months of age was correlated with the requirement at each later time-point. The daily dose was modified less frequently in patients with in situ thyroid (36 %) than in patients with ectopic gland (41.4 %) or with athyreosis (43.6 %). Patients with in situ gland required a lower dose than the other two subgroups. The dose at 6 months seems predictive of the requirement until 12 years of age. Euthyroidism may be achieved in pre-school and in-school patients by 3–4 and 2–3 µg/kg/day (70–90 and 60–80 µg/m2/day) of levothyroxine, respectively.
AB - The aim of the replacement therapy with levothyroxine in congenital hypothyroidism (CH) is to correct hypothyroidism and ensure normal growth and neuropsychological development. Few data are available about the appropriate dose during childhood and early adolescence; therefore, we performed a multicenter observational study in a large population of patients with CH to assess the required levothyroxine dose to obtain euthyroidism. We recruited 216 patients with permanent CH classified into three groups (agenesia, ectopia, and in situ gland) on the basis of the thyroid imaging. The levothyroxine dose was recorded at 6 and 12 months and then yearly until 12 years of age. The daily levothyroxine requirement progressively decreased during the follow-up, irrespective of etiology. It was significantly lower in patients with in situ gland than in patients with athyreosis during the entire study period and with ectopic gland from the age of 1 year. The levothyroxine requirement at 6 months of age was correlated with the requirement at each later time-point. The daily dose was modified less frequently in patients with in situ thyroid (36 %) than in patients with ectopic gland (41.4 %) or with athyreosis (43.6 %). Patients with in situ gland required a lower dose than the other two subgroups. The dose at 6 months seems predictive of the requirement until 12 years of age. Euthyroidism may be achieved in pre-school and in-school patients by 3–4 and 2–3 µg/kg/day (70–90 and 60–80 µg/m2/day) of levothyroxine, respectively.
KW - Congenital hypothyroidism
KW - Congenital hypothyroidism etiology
KW - Congenital hypothyroidism severity
KW - Replacement therapy
KW - Thyroxine requirement
UR - http://www.scopus.com/inward/record.url?scp=84949102334&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84949102334&partnerID=8YFLogxK
U2 - 10.1007/s12020-015-0574-1
DO - 10.1007/s12020-015-0574-1
M3 - Article
C2 - 25762444
AN - SCOPUS:84949102334
VL - 50
SP - 674
EP - 680
JO - Endocrine
JF - Endocrine
SN - 1355-008X
IS - 3
ER -