Low circulating testosterone and estradiol levels are found in men with congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome (KS). It is uncertain if the bone structure is impacted. To investigate bone geometry, volumetric density, and microarchitecture in CHH/KS patients. This cross-sectional study comprised 51 genotyped CHH/KS patients and 40 healthy volunteers from a single French tertiary academic medical facility. 98 percent of CHH/KS males had received testosterone and/or combination gonadotropins. Volumetric bone mineral density (vBMD) and cortical and trabecular microarchitecture were determined using high-resolution peripheral quantitative computed tomography, dual-energy x-ray absorptiometry (DXA), and serum bone marker measurements. CHH and controls did not differ in terms of age, BMI, or vitamin D and PTH levels. DXA revealed decreased areal bone mineral density (aBMD) in CHH/KS in the lumbar spine, whole hip, femoral neck, and distal radius despite long-term hormonal therapy. HR-pQCT indicated reduced cortical and trabecular vBMD as well as cortical thickness at the tibia and radius, which was consistent with persistently higher serum bone markers. The trabecular microarchitecture of CHH/KS males was changed, with a significant reduction in trabecular thickness. Furthermore, CHH/KS males had a smaller cortical bone area, whereas total and trabecular bone areas were larger exclusively on the tibia. Early treatment initiation resulted in a substantial improvement in trabecular bone volume/tissue volume and trabecular vBMD at the tibia.

Despite long-term hormonal therapy, CHH/KS men’s vBMD and bone microarchitecture remain compromised. Adolescent treatment beginning is related to improved trabecular outcomes, emphasizing the need for early diagnosis.

Reference: https://academic.oup.com/jcem/article-abstract/106/9/e3312/6174303?redirectedFrom=fulltext