Severe osteoporosis with multiple vertebral fractures after gender reassignment therapy - is it male or female osteoporosis?

Objective. We report about a 49-years-old patient with severe osteoporosis and multiple vertebral fractures after male-to-female reassignment therapy. The patient had 12 years of hormone replacement therapy (HRT) with very low serum levels of estradiol and testosterone at the time the fractures occurred. The reasons are currently not known. Most likely the patient seems to be non-compliant with the HRT intake. Results. Bone mineral density (BMD) measurements showed highly decreased T-Scores between -3.5 and -4.5. All routine laboratory parameters, especially the markers of bone turnover, were within the normal range. mu-CT 3D-structural analysis of the bone biopsy showed a highly reduced trabecular connectivity (Conn. Dens.). Bone mineral density distribution (BMDD), measured by quantitative backscattered electron imaging (qBEI), showed a BMDD within normal range, except heterogeneity index (Ca(WIDTH)) and fraction of highly mineralised bone (Ca(HIGH)), which were increased. Conclusions. We conclude that our patient has a cross-sex hormonal therapy induced total imbalance of bone homeostasis, because of the long lasting under monitored hormone therapy which led to severe interferences in physiological maturities. Male-to-female transsexuals without an adequate estrogen treatment are at increased risk of developing osteoporosis.