Thyroid Function Tests

TSH, free T4/T3, thyroid antibodies, and clinical interpretation

Lakshmi Nair, 62F

TFT-2026-0441 · SLE — monitoring for thyroid disease (autoimmune) · Dr. R. Kumar (Rheumatology)

Overt Hyperthyroid
AnalyteValueUnitReferenceFlag
TSH (Thyroid Stimulating Hormone)0.02 mIU/L0.35–5.50
Suppressed
Free T4 (FT4)28.4 pmol/L9.0–19.1
High
Free T3 (FT3)9.2 pmol/L2.6–5.7
High
Anti-TPO Antibodies> 600 IU/mL< 34
High
Anti-Thyroglobulin Antibodies420 IU/mL< 115
High
Overt hyperthyroidism: suppressed TSH with elevated FT4 and FT3. Markedly elevated Anti-TPO and Anti-Tg antibodies — consistent with Graves' disease or autoimmune thyroiditis (Hashimoto's thyrotoxic phase). Urgent endocrinology referral. Consider antithyroid drugs (carbimazole). ECG for atrial fibrillation.

Asha Patel, 24F

TFT-2026-0440 · Pre-conception counselling — known hypothyroidism on levothyroxine · Dr. S. Mehta (Gynaecology)

Sub-optimal
AnalyteValueUnitReferenceFlag
TSH2.8 mIU/L0.35–2.5 (pre-conception target)
High
Free T4 (FT4)14.2 pmol/L9.0–19.1
Normal
TSH 2.8 — above target of < 2.5 for pre-conception. Increase levothyroxine dose from 75 mcg to 100 mcg. Recheck in 4-6 weeks. Target TSH < 2.5 before conception and maintain < 4.0 in pregnancy.