A 15-year-old girl presents with primary amenorrhea and short stature. Vital signs show BP 138/82 mmHg, HR 78/min, RR 16/min, temp 37°C. Physical examination reveals webbed neck, widely spaced nipples, and cubital valgus. Laboratory studies demonstrate elevated FSH of 62 mIU/mL (normal 5-25) and low estrogen at 8 pg/mL. Karyotype analysis shows 45, X. Cardiac ultrasound is normal. She takes no medications. Which chromosomal abnormality best explains these findings?
- A)Hypothalamic GnRH deficiency with anosmia
- B)Activating mutation in Gs alpha
- C)46 XY karyotype with androgen receptor defect
- D)45 XO karyotype with streak ovariesGABARITO
- E)47 XXY karyotype with seminiferous tubule dysgenesis
Explicação
Turner syndrome is caused by monosomy X and leads to gonadal dysgenesis with streak ovaries. Loss of ovarian estrogen feedback produces elevated FSH and LH, resulting in hypergonadotropic hypogonadism. Short stature and webbed neck are classic phenotypic clues... Ver explicação completa e trilha adaptativa →