Bone mineral density in children and adolescent females treated with high doses of L-thyroxine.
Single-photon absorptiometry was used to assess forearm bone mineral content (BMC) at a proximal site (PBMC) and at a more distal site (DBMC) of the non-dominant distal forearm in 20 children and adolescent females taking high doses of L-thyroxine (120 micrograms/m2/day) for a period of 6-96 months for endemic goiter, Hashimoto's thyroiditis or thyroid cancer. PBMC was significantly reduced compared to controls (p < 0.002). No correlation was found between PBMC, the values of circulating thyroid hormones and the indices of tissue hyperthyroidism such as TSH and systolic time intervals (STI), suggesting that bone is a very sensitive target for thyroid hormones. Further studies are necessary to confirm our findings and to verify their clinical significance. At present, we believe that suppressive doses of L-thyroxine should be reserved for cancer patients only.
Radetti
G
G
Department of Pediatrics, General Hospital of Bolzano, Italy.
Castellan
C
C
Tatò
L
L
Platter
K
K
Gentili
L
L
Adami
S
S
D000293:Adolescent; D015519:Bone Density; D002648:Child; D005260:Female; D005542:Forearm; D006043:Goiter, Endemic / Q000188:drug therapy; D006801:Humans; D008297:Male; D013599:Systole; D013963:Thyroid Hormones / Q000097:blood; D013964:Thyroid Neoplasms / Q000188:drug therapy; D013967:Thyroiditis, Autoimmune / Q000188:drug therapy; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use
D013963:Thyroid Hormones; D013972:Thyrotropin; D013974:Thyroxine