Linked Life Data

2588121

Source:http://linkedlifedata.com/resource/pubmed/id/2588121

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1990-1-8
pubmed:abstractText
The usual recommendation is to follow total triiodothyronine (T3) concentration during levothyroxine (L-thyroxine) therapy because 65% of clinically euthyroid patients receiving L-thyroxine have normal T3 but elevated total thyroxine (T4) levels. Because free thyroxine (FT4) is the metabolically active form of T4, our study was designed to determine whether FT4 by analog radioimmunoassay method is normal or increased in euthyroid patients receiving L-thyroxine. Twenty-seven clinically euthyroid patients, 5 males and 22 females, receiving L-thyroxine for thyroid suppression, were studied in a prospective protocol. Twenty-one euthyroid patients not receiving L-thyroxine served as controls. Samples were analyzed for T4, T3, T3 (RU), TSH, and FT4 by three analog methods. Mean FT4 levels were greater than control for all three assays. The percentage of patients with FT4 in the hyperthyroid range was 63% for assay I, 41% for assay II, and 52% for assay III. When patients were grouped by dose of L-thyroxine, FT4 levels were not significantly increased. Sixty-two percent of patients receiving L-thyroxine had T4 levels in the hyperthyroid range. T3 concentrations were not significantly greater in the L-thyroxine group when compared with control. In the L-thyroxine group, thyrotropin was significantly less than in the control group. FT4 concentration by analog method is in the hyperthyroid range in as many as 63% of clinically euthyroid patients receiving L-thyroxine. The use of FT4 to assess thyroid status may cause inappropriate adjustment of L-thyroxine dose. T3 level continues to parallel closely the physician's clinical impression and best represents peripheral metabolic status.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0039-6060
pubmed:author
pubmed:issnType
Print
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
951-5
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Plasma free thyroxine concentrations in patients receiving levothyroxine for thyroid suppression.
pubmed:affiliation
Department of Internal Medicine, Mary Imogene Bassett Hospital, Cooperstown, N. Y. 13326.
pubmed:publicationType
Journal Article