Which physical examination finding is most consistent with hypothyroidism in a patient with elevated TSH and low free T4?

Which physical examination finding is most consistent with hypothyroidism in a patient with elevated TSH and low free T4?

• A. Brittle fingernails
• B. Ophthalmopathy
• C. Pitting edema
• D. Skin hyperpigmentation

Answer: (A)

In primary hypothyroidism, the body's metabolic activity slows, and this affects the skin and its appendages. Brittle fingernails arise from reduced protein synthesis and slower turnover of keratin, which is a common exam finding when thyroid hormone levels are low despite a high TSH. This aligns with elevated TSH and low free T4, indicating underactivity of the thyroid. Ophthalmopathy is characteristic of Graves disease, a hyperthyroid condition driven by autoimmune stimulation of the TSH receptor, not hypothyroidism. Pitting edema is not typical in hypothyroidism; the edema of myxedema is usually nonpitting due to mucopolysaccharide deposition in the interstitial spaces. Skin hyperpigmentation is not a classic feature of hypothyroidism and more often points to other endocrine disorders, such as adrenal insufficiency. So brittle fingernails best reflect the slowed metabolic state of hypothyroidism in this context.

In primary hypothyroidism, the body's metabolic activity slows, and this affects the skin and its appendages. Brittle fingernails arise from reduced protein synthesis and slower turnover of keratin, which is a common exam finding when thyroid hormone levels are low despite a high TSH. This aligns with elevated TSH and low free T4, indicating underactivity of the thyroid.

Ophthalmopathy is characteristic of Graves disease, a hyperthyroid condition driven by autoimmune stimulation of the TSH receptor, not hypothyroidism. Pitting edema is not typical in hypothyroidism; the edema of myxedema is usually nonpitting due to mucopolysaccharide deposition in the interstitial spaces. Skin hyperpigmentation is not a classic feature of hypothyroidism and more often points to other endocrine disorders, such as adrenal insufficiency.

So brittle fingernails best reflect the slowed metabolic state of hypothyroidism in this context.