A 15-year-old girl is brought to the gynecology clinic by her mother for evaluation of absent menses. On physical examination, she is at the 5th percentile for height. She has Tanner stage 1 breast development and normal external female genitalia. Arrange the following steps in the correct chronological order for the standard algorithmic diagnostic evaluation and subsequent workup of this patient.
- 1Perform a pelvic ultrasound to evaluate the internal reproductive organs
- 2Measure serum follicle-stimulating hormone (FSH) levels
- 3Obtain a karyotype analysis
- 4Order a transthoracic echocardiogram
Answer
The correct sequence is: Pelvic ultrasound, followed by serum FSH levels, then karyotype analysis, and finally a transthoracic echocardiogram.
The correct diagnostic algorithm for primary amenorrhea with absent breast development starts with a pelvic ultrasound to confirm the presence of a uterus. Since the uterus is present, serum FSH is measured next to distinguish between central (hypothalamic or pituitary) and peripheral (ovarian) causes. Elevated FSH indicates primary ovarian insufficiency. In this context (especially given the patient's short stature), a karyotype is then performed to diagnose Turner syndrome. Finally, once Turner syndrome is diagnosed, an echocardiogram is essential to screen for life-threatening cardiac defects.
Step-by-Step Solution
Key Concept
Evaluation of primary amenorrhea in a patient with absent secondary sexual characteristics involves sequentially confirming the presence of a uterus, measuring FSH to localize the defect, and obtaining a karyotype if primary ovarian insufficiency is identified.
Estimated Time:1m 0s