A 19-year-old man presents with infertility and gynecomastia. Vital signs are normal (BP 118/76, HR 72, RR 16, Temp 37°C). Physical examination reveals tall stature with disproportionately long limbs, small firm testes bilaterally, and mild gynecomastia. Laboratory studies show elevated FSH (18 mIU/mL), elevated LH (16 mIU/mL), and low testosterone (120 ng/dL). Semen analysis reveals azoospermia. He denies anabolic steroid use. Which karyotype best explains these findings?
- A)47 XYY
- B)45 XO
- C)46 XY
- D)Mosaic trisomy 21
- E)47 XXYGABARITO
Explicação
Klinefelter syndrome is caused by an extra X chromosome, most commonly 47 XXY. Primary testicular failure leads to low testosterone with elevated gonadotropins, small firm testes, infertility, and gynecomastia. Tall stature with eunuchoid body proportions is c... Ver explicação completa e trilha adaptativa →