In 10 patients, 8 males and 2 females, suffering from idiopathic hemochromatosis (IH), the gonadotropic function has been studied using the GnRH test (iv administration of 100 micrograms) to make precise the pathogenesis of their hypogonadism. The FSH and LH mean basal levels were low and almost unaffected by GnRH (p < 0.001 at each time value when compared to controls). The hypogonadism often observed during the course of IH seems to be hypogonadotropic. Various factors could be responsible for this disturbance. The exact site of the lesion, whether hypothalamic or hypophyseal, remains unknown.

17-Ketosteroids↗

PubMedDate not supplied

Plasma 21-deoxycortisol: comparison of a time-resolved fluoroimmunoassay using a biotinylated tracer with a radioimmunossay using (125)iodine.

Plasma 21-deoxycortisol (21DF) is an excellent marker of 21-hydroxylase deficiency. Currently, it is the only marker able to detect heterozygous carriers with 21-hydroxylase deficiency after ACTH stimulation. We have already developed radioimmunoassays for 21DF using first tritiated, then 125I-21DF which had a ten-fold higher sensitivity. However, because the lifespan of 125I-21DF is short, the tracer needs to be reprepared every two months and this multiplies the risk of contamination by radioactive 125I vapours. We therefore developed a non-isotopic 21DF assay that uses a 21DF-biotin conjugate with a original bridge, a diaminopropyl arm, linking the steroid to biotin. The 21DF-biotin conjugate was measured by time-resolved fluorescence after adding streptavidin-europium to the microtitration wells. The analytical qualities of this assay were very similar to those of the radioimmunoassay using 125I-21DF as tracer. The results obtained by the two methods, in either normal subjects or patients with 21-hydroxylase deficiency, were virtually the same.

Adrenal Hyperplasia, Congenital↗