A 54-year-old female is evaluated for fatigue, constipation and cold intolerance. On physical examination, skin is dry, periorbital edema and thyroid gland in normal in size with no nodules. Serum Na is 129 mEq/L (Normal: 135-145), TSH is 1.4 mU/L (Normal: 0.5-5.0)
سؤال مجاني 1 من 10 اليوم · اشترك وكمّل بدون حد
اعرض الإجابة
الإجابة والشرح
ادخل لحسابك عشان نحفظ إجاباتك ونوريك أخطاءك.
الإجابة: A. Free thyroxine (T4) measurement
Clear hypothyroid features (plus hyponatraemia) with a normal TSH suggest central (secondary) hypothyroidism, where TSH may be low or inappropriately normal. TSH alone cannot rule this out — measure free T4. Repeating TSH would miss the diagnosis, and scintigraphy/ultrasound do not assess central disease.
ليش كل خيار صح أو غلط
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A
ليش صح
TSH is low or normal in secondary (central) hypothyroidism, so a normal TSH does not exclude it; free T4 is low in overt hypothyroidism and is the next test.
✓ Thyroid disorders.pdf · p. 9 -
B
ليش غلط
Repeating TSH would not help: TSH can be low or normal in secondary hypothyroidism, so free T4 is needed to confirm or rule out the diagnosis.
✓ Thyroid disorders.pdf · p. 9 -
C
ليش غلط
A radioiodine uptake test only measures how much iodine the thyroid takes up (decreased in hypothyroidism); it does not show a central cause, whereas free T4 confirms the diagnosis.
✓ Thyroid disorders.pdf · p. 9 -
D
ليش غلط
Ultrasound shows gland size, structure and blood flow and mainly helps rule out mimics; this gland is normal in size without nodules, so it adds little here.
✓ Thyroid disorders.pdf · p. 9
- المصدر
- Thyroid disorders.pdf · p. 9
- المحاضرة
- Thyroid Disorders · Endocrinology · Module B
- ظهر في
- Endo bank