Endocrine Abstracts

We present two cases where, without measurement of cortisol binding globulin (CBG), interpretation of their 250mcg short synacthen test (SST) would have falsely suggested inadequate pituitary-adrenal reserve.A 62yr old woman was referred with an incidental finding of a pituitary adenoma. Pituitary function tests confirmed gonadotrophin and growth hormone deficiency. Initial and subsequent SSTs were normal (30min cortisol reater than 600nmol/L). Follow up...

Lithium blocks the release of organic iodine and thyroid hormone from the thyroid gland without affecting thyroidal radioactive iodine (RAI) uptake. From August 2001, we have been using lithium carbonate 800mg nocte as an adjunct to RAI treatment for thyrotoxicosis. Antithyroid medication is stopped and lithium started 3 days before RAI. Lithium is continued for 10 days in total with levels checked at 3 and 10 days. Thyroid function tests (TFTs) are measured 1, 3, 6, 9 and 12 ...

Significant delays in follow up and institution of thyroxine replacement for patients developing post-radioiodine (RAI) hypothyroidism were revealed by a three year retrospective audit. To reduce the incidence of undiagnosed early hypothyroidism and lengthy waits between outpatient visits, a telephone clinic was introduced in August 2000. Thyroid function tests are checked at 3, 6, 9 and 12 weeks post-treatment. Results are checked weekly by a Specialist Registrar. Patients wh...

Following the establishment of a telephone clinic follow-up for patients receiving radioiodine for recurrent thyrotoxicosis, we wished to further improve our results in achieving hypo(eu)thyroidism while minimising the risk of transient hyperthyroidism and thyroid storm post-therapy. Although not widely used, lithium has been shown to increase the effectiveness of radioiodine therapy, leading to prompter control of hyperthyroidism. Since August 2001, patients undergoing radioi...

Recent studies suggest TSH inhibits bone remodeling, indicating that TSH deficiency rather than thyroid hormone excess could cause bone loss in thyrotoxicosis. The findings predict that TSH receptor (TSHR) stimulating antibodies (TSHRAb) should inhibit bone turnover, whereas Graves’ disease patients exhibit high bone turnover with increased fracture susceptibility. We characterized TSH-action in primary human and mouse osteoblasts and osteoclasts, and explored whether a p...

In August 1999, to reduce pressure on an overcrowded outpatient department and the incidence of undetected early hypothyroidism, we implemented a new protocol for the follow-up of patients undergoing radioiodine treatment for recurrent thyrotoxicosis. Suitable patients are invited to participate in follow-up by telephone. Thyroid function tests are checked at 3, 6, 9 and 12 weeks post-treatment. Patients who become hypothyroid post-treatment (fT4 <14 picomoles per litre) a...

Studies of TSHR−/− mice suggest that TSH inhibits bone turnover, but these mice have congenital hypothyroidism and the actions of TSH cannot be separated from effects of thyroid hormone deficiency. We characterised skeletal development in hyt/hyt mice, which have a point mutation in the Tshr gene, and Pax8−/− mice with thyroid gland agenesis. Hyt/hyt mice have a 100-fold increase in TSH but inactive TSHRs, whereas Pax8&...