Endocrine Abstracts

Introduction: The quality of testosterone assays has been a matter of debate for several years. Known limitations of testosterone immunoassays are the cross-reactivity with other steroids and a high variation in the low concentration range. We hypothesized that one of the additional limitations of testosterone immunoassays is an ineffective displacement of testosterone from its binding protein.Methods: Thirty samples from women not using oral contracepti...

Background: Autoimmune hypophysitis can result in growth hormone deficiency (GHD). Although autoimmune hypophysitis is uncommon, it is associated with other autoimmune endocrine diseases like autoimmune hypothyroidism (AIH). Recent studies suggest a high prevalence (5%) of GHD in AIH, which could contribute to the reduced quality of life frequently observed in patients with AIH despite adequate treatment with thyroxine.Objective: To establish the prevale...

1,25-dihydroxyvitamin D3, the hormonally active metabolite of vitamin D3, tightly controls calcium blood levels. An increase of 1,25-dihydroxyvitamin D3 leads to an increase in calcium concentration with calcium originating from various resources, including bone tissue. To assess a patient’s vitamin D status the precursor metabolite 25-hydroxyvitamin D3 is determined. However, measurement of 1,25-dihydroxyvitamin D is required w...

Context: Loss-of-function of immunoglobulin superfamily 1 (IGSF1) causes an X-linked syndrome of central hypothyroidism, macroorchidism, and variable prolactin deficiency, GH deficiency in childhood, delayed pubertal testosterone rise, and/or obesity. The clinical features advert towards a pivotal role for IGSF1 in the pituitary gland, but detailed knowledge on pituitary hormone secretion in this syndrome is lacking.Objective: To study detailed ...

X-linked IGSF1 (immunoglobulin superfamily, member 1) loss-of-function mutations in males are associated with central hypothyroidism, macroorchidism, and a variable spectrum of anterior pituitary dysfunction. Igsf1 deficient male mice also exhibit central hypothyroidism, however, the physiological and molecular function of IGSF1 in both species has not yet been elucidated. Although partial transient GH deficiency is a ra...

X-linked IGSF1 (immunoglobulin superfamily, member 1) loss-of-function mutations in males are associated with central hypothyroidism, macroorchidism, and a variable spectrum of anterior pituitary dysfunction. Igsf1 deficient male mice also exhibit central hypothyroidism, however, the physiological and molecular function of IGSF1 in both species has not yet been elucidated. Although partial transient GH deficiency is a ra...