A 15-year-old girl presents with primary amenorrhoea. Examination shows short stature (145 cm), a broad shield chest with widely spaced nipples, cubitus valgus, and no breast development. Which investigation will most likely establish the diagnosis?
- A Karyotype analysis ✓
- B Serum testosterone level
- C Pelvic MRI
- D Serum prolactin
Correct answer: A. Karyotype analysis
Explanation
The phenotype of short stature, shield chest, widely spaced nipples and cubitus valgus with absent secondary sexual characteristics is classic for Turner syndrome (45,X). Diagnosis is confirmed by karyotype. Pelvic MRI would show a streak uterus but does not give the chromosomal cause. Testosterone is normal or low female range here; it is the discriminating test in androgen insensitivity, where stature is tall rather than short.
Reference: Williams Gynecology, 4th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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