…thyroid hormone receptor beta (THRB) gene. The mutant receptor has lower binding affinity for thyroid hormone and, as a consequence, serum thyroid-stimulating hormone (TSH) levels remain nonsuppressed despite elevated thyroid hormones (Dumitrescu and Refetoff 2013 Biochim Biophys Acta. 1830:3987–4003). Patients with pathogenic variants in…View
RET GENE ANALYSIS IN FAMILIAL MEDULLARY THYROID CARCINOMA & ANALYSIS OF RET AND RAS GENES IN SPORADIC MEDULLARY THYROID CARCINOMA
Familial Medullary Thyroid Cancer (FMTC) is characterised by the presence of medullary thyroid cancer (MTC) in the absence of phaeochromocytoma or parathyroid
…TPOAb. Subjects with subclinical hypothyroidism who are thyroid peroxidase antibody positive should have an annual thyroid function test.
Subjects with subclinical hypothyroidism who are thyroid peroxidase antibody negative should have repeat thyroid function testing approximately every 3 years.
Once a biochemical…View
…with, and presumably is a consequence of, thyroid dysgenesis. In these cases, the thyroid gland can be absent (agenesis), ectopically located, and/or severely reduced in size (hypoplasia). Thyroid dysgenesis is due to pathogenic variants in the FOXE1, GLIS3, NKX2-1, PAX8, THRA and TSHR genes.
…thyroid cancer, or secondary hypothyroidism due to pituitary or hypothalamic disorders.
If TSH >4.5 Patient Undertreated – if taking medication as prescribed, increase dose and retest in 4-6 weeks. This guidance is not applicable for pregnancy, thyroid cancer, or secondary hypothyroidism due to pituitary…View
Please note: TSH is done as a first line test for all thyroid function requests. If the TSH is abnormal, then a fT4 is cascaded. Marking “On T4” does not automatically result in a fT4 request being made. Please take care to appropriately mark
The Exeter laboratory thyroid function test testing strategy uses TSH as a front-line test.
Secondary hypothyroidism due to pituitary disease will be difficult to detect using TSH as a front-line test, and cannot be expected to be picked up as a matter
…undetectable in pituitary disease and thyrotoxicosis but also in some cases of euthyroid ophthalmic Grave’s disease and multinodular goitre.
A late rise in TSH may be seen rarely in thyroid and pituitary disease as well as hypothalamic disease.
Hall et al., Lancet…View
…characterised by the presence of mucosal neuromas of lips and tongue as well as distinctive facies with enlarged lips, a ‘marfanoid’ body habitus and medullary thyroid cancer.
Patients with Familial Medullary Thyroid Cancer (FMTC) have medullary thyroid cancer (MTC) without additional MEN2A or…View