Endocrine Abstracts

Adult growth hormone replacement is currently given by daily sc injections in the vast majority of children and adults treated for growth hormone (GH) deficiency. In recent years, sustained-release preparations of GH have been developed; the preparations available so far maintained therapeutic GH concentrations for approximately 14 days, but were characterised by a dominant early release, which resulted in high supraphysiological early GH peaks, and a rapid decline thereafter....

One study examining the lipid profile of adults with partial GH deficiency (GH insufficiency, GHI) suggested they are dyslipidaemic. We defined GH status using two stimulation tests, the ITT and AST, in to patients with severe GHD (pGH < 3ng/ml, n = 30) or GHI (pGH 3 - 7ng/ml, n = 24). Thirty age and gender matched controls were studied.There were no differences in age between the GHD, GHI, and control subjects (30.9 vs 31.5 vs 34.2 yrs). IGF-I levels...

The hypothalamic-pituitary-thyroid axis can be affected following therapy for brain tumours. Primary thyroid damage is frequent following craniospinal irradiation(CSI). Central hypothyroidism is less commonly reported following cranial irradiation(CI), however, some investigators have argued it is underdiagnosed and may be more prevalent than growth hormone deficiency(GHD). Utilising thyroid function tests(TFT) for the diagnosis of central hypothyroidism is notoriously difficu...

Decreased GH secretion and increased GH clearance contribute to low GH levels found in obesity; in spite of which IGF-1 levels are reported as normal. To explain the discordancy between GH and IGF-1 status in obese subjects, an increase in peripheral (hepatic) sensitivity to GH activity has been hypothesized. Previously peripheral responsiveness to GH in obesity has been investigated and reported to be increased, however the use of weight-based GH doses made interpretation dif...

OBJECTIVE: To quantify the extent of change in total body water (TBW) and nature of its relationship with changes in body composition, measured by direct methods, during physiological GH replacement in severely GHD adults.METHODS: Thirty (16 female, age range 17-65 years) severely GHD adults were studied. Patients with diabetes insipidus, cardiovascular or renal disease requiring diuretic therapy were excluded. Patients with other pituitary deficits had ...

OBJECTIVE: To determine whether the quality of life improvement, observed with long-term physiological GH replacement, is correlated with favourable changes in body composition or total body water (TBW) measured by direct methods.METHODS: Thirty (16 female, age range 17-65 years) severely GHD adults were studied. Patients with diabetes insipidus, cardiovascular or renal disease requiring diuretic therapy were excluded. Patients with additional pituitary ...

OBJECTIVE: To investigate the association between APD, treated Cushing's disease and severe hypopituitarism.METHODS: Fifty-seven patients (42 female), in remission after treatment for Cushing's disease, were studied. The cohort comprised 13 patients with, and 44 without APD. APD was defined as a serum prolactin persistently below the detection limit of the assay. Age and gender did not significantly differ between sub-groups.RESULT...

The diagnosis of GHD is based on GH stimulation tests. The test of choice is the ITT and a peak GH response of less than 9mU/L is considered diagnostic of GHD. Peak GH values of less than 20mU/L during an ITT are infrequently observed in healthy adults. In hypopituitary patients a peak GH values to the ITT of 9-20 mU/L likely represents a state of partial GHD, or GH insufficiency (GHI). To investigate if patients with GHI have similar features to GHD adults we assessed body co...

The thyroid hormones, L-thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are essential for skeletal development and regulate bone mineralisation in the adult. T4 is a pro-hormone that is converted to active T3 by the type I and II 5'-iodothyronine deiodinase enzymes (D1 and D2). T4 and T3 are substrates for the type III 5-deiodinase enzyme (D3) which catalyses the irreversible production of inactive metabolites. The deiodinases are expressed widely in T3-target tissues and the...

Objective: To identify a range of IGF-I values representative of growth hormone deficiency (GHD), which could be utilised to reduce the risk of 'functional' GHD in Pegvisomant treated acromegaly.Method: We analysed centrally measured IGF-I data from the KIMS European GHD database. We stratified this cohort into six gender based, age ranges and assessed IGF-I and IGF-I standard deviation scores (SDS).Results: Baseline measurements f...