ESPE Abstracts

Introduction: Turner syndrome is a relatively common chromosomal abnormality affecting 1:2000 girls. Virilization can occur in girls with Turner syndrome which is in most cases associated with the presence of an Y chromosome. Mosaicism is found in 25% of the karyotypes, in 6% of those the Y chromosome is present. This could lead to development of androgen producing gonadoblastoma/dysgerminoma. Active screening to search for Y chromosomal material is included in the international guidelines and prophylactic gonadectomy is advised. We present a case of a girl with virilization without the presence of Y chromosomal material.

Case presentation: A 16 year old girl presented with progressive hirsutism, deepening of the voice and clitoromegaly since 6 months. Her medical history is unremarkable. Puberty started at the age of 13, she had normal breast development (Tanner 4), menarche did not yet occur. Biochemistry revealed high testosterone levels (9 [0,5-2,0] nmol/L) and high gonadotropins (LH 53 [2.4-12.6 ] IU/l, FSH 120 [3.5-12.5] IU/L), estradiol was relatively low with 39 [45-854] pmol/l and AMH was undetectable (<0,1ug/l). Karyotyping and micro-array showed an 46,X,del(X)(q22.1) [82]/45,X [18] karyotype. FISH showed no signs of Y chromosomal material in urine and buccal mucosa. Tumor markers (βHCG and AFP) were negative. MRI abdomen and whole exome sequencing showed no abnormalities. Urine and serum steroid profile showed an isolated high testosterone with normal values for the other steroids. After receiving the results of the diagnostic tests, she was treated with a GnRH analogue and 1mg 17-Beta-estradiol. This successfully repressed both the gonadotropin (LH 5,3IU/l, FSH 1,7IU/L) and testosterone (0,72nmol/l) levels, indicating that testosterone levels were gonadotrophin dependent and derived from the gonad(s). In addition, low AMH levels suggest a negligible follicle reserve. We concluded that the girl suffered from her testosterone producing gonads while fertility was unreachable. As such gonadectomy was indicated. There were streak ovaries with bilateral ovarian hilus cell hyperplasia and in the left ovary a hilus cell tumor. Biochemistry 6 weeks after gonadectomy showed normalization of testosterone (0,39nmol/L) and gonadotrophins (LH 6,8IU/l, FSH 15IU/L).

Conclusion: Due to ovarian insufficiency a sudden rise in gonadotropins may overstimulate hilus cells that are still responsive to gonadotropins, causing the production of testosterone and fast progression of virilization. Short acting GnRH analogues could serve as a diagnostic tool to determine whether testosterone production is gonadotrophin dependent and prevent further virilization while awaiting results diagnostic workup.