Subclinical hypothyroidism is defined by which pattern, and what is the recommended management?

• A. Slightly elevated TSH >5.0 with normal T4/T3; DO NOT TREAT; RECHECK 6 MONTHS
• B. Elevated TSH with low T4
• C. Normal TSH with normal T4
• D. TSH suppressed with high T4

Answer: (A)

Subclinical hypothyroidism shows a mild rise in TSH with a normal free T4 (and typically normal free T3). That pattern means the pituitary is compensating for slightly reduced thyroid activity, but circulating thyroid hormone remains in the normal range. Because thyroid hormone levels are still normal and many people feel fine, the usual approach is not to start treatment right away. Instead, observe and recheck TSH in about six months to see if it persists or progresses. Treatment is considered if TSH remains elevated and rises further (often >10), or if the patient is pregnant or planning pregnancy, or has other risk factors like autoimmune disease or cardiovascular risk. Other patterns—elevated TSH with low T4 indicates overt hypothyroidism, normal TSH with normal T4 is euthyroid, and suppressed TSH with high T4 indicates hyperthyroidism—do not fit subclinical hypothyroidism.