Nov. 05' : Thyroid Disorders in Down Syndrome
Juan José Chillarón Jordán1, Alberto Goday Arno11, 2 María José Carrera Santaliestra1, Juana Antonia Flores Le Roux1, Jaume Puig de Dou1, Juan Francisco Cano Pérez1
1 Endocrinology and Nutrition Service. Hospital Universitari del Mar de Barcelona. Facultat de Medicina. Universitat Autònoma de Barcelona.
2 Endocrinologist at Centre Mèdic Down
Correspondence to:
Dr. Alberto Goday Arno.
Servei d’Endocrinologia i Nutrició.
Hospital del Mar.
Passeig Marítim 25-29.
08003 Barcelona.
E-mail: agoday@imas.imim.es
Article received: 31-Oct-05
Abstract
Thyroid dysfunctions are important among the conditions associated with Down Syndrome (DS), due to their high prevalence and to their potential impact on quality of life. That is why routine TSH, T4 and T3 determination must be carried out at regular intervals on all patients with DS.
Hypothyroidism is common in DS patients, and levothyroxine replacement therapy must be started if TSH levels exceed 10 mcU/mL, T3 or T4 levels are low, or antithyroid antibody titres are high. A need for cardiac surgery is also an indication. It is advisable to start with a low-dose treatment (12.5 µg/day) and then adjust it until TSH levels have been normalized.
Slight and usually transitory minor subclinical hypothyroidism is a common occurrence in the first three years of life, and the need for treatment with levothyroxine is to a certain extent disputed. In this respect, a recent clinical trial showed an improvement in terms of psychomotor development in a group of patients treated with levothyroxine from the neonatal period. Follow-up in the trial was carried out for 24 months, and the improvement in psychomotor development was estimated at 0.7 months, while allowing for the possibility of magnified differences in subsequent checks.
Regarding hyperthyroidism in DS, although it arises in a higher percentage than among the general population, it has a much lower incidence than hypothyroidism. The most frequent etiology is toxic diffuse goitre, or Graves-Basedow disease, which is initially treated with synthetic antithyroids (metimazol or carbimazol) and beta-adrenergic blocking agents (propranolol or atenolol). Where hyperthyroidism persists, a definitive treatment must be considered, preferably with radioiodine, given the advantages it offers over surgery (with its attendant hospital stay, anaesthesia, and so on.).
Keywords: Diabetes mellitus. Hyperthyroidism. Hypothyroidism. Obesity. Low height.
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1 Endocrinology and Nutrition Service. Hospital Universitari del Mar de Barcelona. Facultat de Medicina. Universitat Autònoma de Barcelona.
2 Endocrinologist at Centre Mèdic Down
Correspondence to:
Dr. Alberto Goday Arno.
Servei d’Endocrinologia i Nutrició.
Hospital del Mar.
Passeig Marítim 25-29.
08003 Barcelona.
E-mail: agoday@imas.imim.es
Article received: 31-Oct-05
Abstract
Thyroid dysfunctions are important among the conditions associated with Down Syndrome (DS), due to their high prevalence and to their potential impact on quality of life. That is why routine TSH, T4 and T3 determination must be carried out at regular intervals on all patients with DS.
Hypothyroidism is common in DS patients, and levothyroxine replacement therapy must be started if TSH levels exceed 10 mcU/mL, T3 or T4 levels are low, or antithyroid antibody titres are high. A need for cardiac surgery is also an indication. It is advisable to start with a low-dose treatment (12.5 µg/day) and then adjust it until TSH levels have been normalized.
Slight and usually transitory minor subclinical hypothyroidism is a common occurrence in the first three years of life, and the need for treatment with levothyroxine is to a certain extent disputed. In this respect, a recent clinical trial showed an improvement in terms of psychomotor development in a group of patients treated with levothyroxine from the neonatal period. Follow-up in the trial was carried out for 24 months, and the improvement in psychomotor development was estimated at 0.7 months, while allowing for the possibility of magnified differences in subsequent checks.
Regarding hyperthyroidism in DS, although it arises in a higher percentage than among the general population, it has a much lower incidence than hypothyroidism. The most frequent etiology is toxic diffuse goitre, or Graves-Basedow disease, which is initially treated with synthetic antithyroids (metimazol or carbimazol) and beta-adrenergic blocking agents (propranolol or atenolol). Where hyperthyroidism persists, a definitive treatment must be considered, preferably with radioiodine, given the advantages it offers over surgery (with its attendant hospital stay, anaesthesia, and so on.).
Keywords: Diabetes mellitus. Hyperthyroidism. Hypothyroidism. Obesity. Low height.
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