Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Thyroid Function Tests”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed1980

Thyroid function tests during carbimazole therapy.

Changes in plasma thyroxine (T4), triiodothyronine (T3), free thyroxine index (FT4I) and thyroid stimulating hormone were studied in 100 patients with Graves' disease treated with carbimazole. During therapy plasma T3 concentrations were disproportionately high compared to those of T4, the T4 : T3 ratio was low, and many patients were clinically euthyroid with a normal plasma T3 but low T4 concentration. Although there was considerable individual variation in response, the order of response was always the same with plasma T4 falling to normal or low levels before T3. Plasma T3 was the best indicator of clinical status and the best predictor of the impending change; additional information of changes in thyroid status was obtained from plasma T4 and FT4I estimation, especially when these were followed sequentially. Single measurements of T4 or FT4I only are not recommended for assessing thyroid function during carbimazole therapy.

Adolescent↗
PubMed1996

How useful is thyroid function testing in patients with recent-onset atrial fibrillation? The Canadian Registry of Atrial Fibrillation Investigators.

BACKGROUND: Patients with recent-onset atrial fibrillation often undergo routine thyroid function screening to rule out thyroid disease as a cause of atrial fibrillation. METHODS: Patients with recent (< 3 months) onset of documented atrial fibrillation or flutter were enrolled in the Canadian Registry of Atrial Fibrillation from outpatient clinics, emergency departments, and hospital wards across Canada. Seven hundred twenty-six patients underwent baseline thyroid function screening and were assessed for presence of clinical thyroid disease. Serum thyrotropin level (TSH) was measured in 707 patients (97%), and thyroxine level (T4) in 407 patients (56%). RESULTS: A TSH level less than 0.1 mU/L was present in 5 patients (0.7%). A TSH level less than normal but more than 0.1 mU/L was present in 34 patients (4.7%). No patient had definite hypothyroidism (TSH > 20 mU/L), but 56 patients (7.7%) had an elevated TSH level that was less than 20 mU/L. During 1.7 years of follow-up, only 7 patients were found to have clinical hyperthyroidism, and 11 patients (1.5%) had hypothyroidism. Logistic regression analysis showed that palpitations (odds ratio, 4.9; 95% confidence interval, 1.7-14.0) and asymptomatic presentation (odds ratio, 5.5; 95% confidence interval, 1.9-16.2) were risk factors for low TSH level, and increasing age (odds ratio, 1.32 every 10 years; 95% confidence interval, 1.01-1.66) was a risk factor for high TSH level. The positive predictive value of palpitations and asymptomatic presentation for low TSH level were 9% and 8%, respectively. CONCLUSIONS: An abnormal TSH level is common in patients with recent-onset atrial fibrillation. However, clinical thyroid disease is uncommon. Routine TSH screening of patients who have atrial fibrillation has a low yield and may be better applied to those patients at higher risk of having undiagnosed clinical thyroid disease.

Atrial Fibrillation↗
PubMedDate not supplied

[Ultrasensitive determination of thyrotropin. Improvement in the performance and reduction of the cost of thyroid function tests].

The characteristics of an ultrasensitive thyrotropin (TSH) assay method using monoclonal antibodies (TSH-U) were determined in euthyroid subjects, either healthy or with extra-thyroid disease, in treated and untreated hyper-and hypothyroid subjects and in subjects under amiodarone. The thyroid function was evaluated by free thyroxine (FT4) and free triiodothyronine (FT3) assays and by TSH tests and TSH response to TRH. With a sensitivity of 1 and a specificity of 0.94, the TSH-U assay proved highly reliable to evaluate the thyroid function. Dysthyroidism can be excluded when TSH-U levels are normal (0.15 to 4.5 microU/ml). In case of low TSH-U level, measurements of FT4 and FT3 and, if required, thyroid gland scintigraphy are necessary to confirm a diagnosis of hyperthyroidism. In contrast, a high TSH-U level is sufficient for affirm diagnosis of hypothyroidism. The TSH-U assay makes the TRH test redundant and can differentiate between hyperthyroxinaemia with euthyroidism and with hyperthyroidism. It is an effective method to detect disorders in thyroid function and it calls for a re-evaluation of thyroid diagnostic strategy.

Adult↗