A 25-year-old lady has put on weight and has oligomenorrhea followed by amenorrhea for 8 months. The blood pressure is 160/100 mm of Hg. Which of the following is the most appropriate investigation?
**Core Concept:** Oligomenorrhea and amenorrhea are symptoms of hypothalamic-pituitary-ovarian axis dysfunction, while hypertension is a late complication of Cushing's syndrome.
**Why the Correct Answer is Right:** A 25-year-old female presenting with oligomenorrhea (infrequent menstruation) and amenorrhea (absence of menstruation) for 8 months, and hypertension, is likely suffering from Cushing's syndrome. Cushing's syndrome is caused by chronic exposure to high levels of cortisol due to adrenal gland disorders, pituitary adenomas, or exogenous corticosteroid use. The hormonal imbalance leads to menstruation disruptions (oligomenorrhea and amenorrhea) and hypertension.
**Why Each Wrong Option is Incorrect:**
A. Hyperthyroidism is another cause of menstruation abnormalities and hypertension, but the clinical picture in this case does not match, as the patient is not overweight, has no goiter, and has no palpitations, tremors, or weight loss.
B. Insulin resistance and type 2 diabetes are more likely causes of menstruation problems, but hypertension is uncommon in these conditions.
C. Polycystic ovary syndrome (PCOS) is a hormonal disorder affecting women of reproductive age, often causing hirsutism, acne, and obesity, but lacks the hypertension.
D. Hypothyroidism can cause oligomenorrhea and amenorrhea, but hypertension is not a common feature of hypothyroidism.
**Clinical Pearl:** Cushing's syndrome is a clinical syndrome that requires a thorough evaluation, including assessing adrenal function, cortisol levels, and imaging studies to diagnose the underlying cause (e.g., adrenal adenoma, pituitary adenoma, or exogenous corticosteroid use).