Makindo Medical Notes

⚠️ Postpartum thyroiditis may be misdiagnosed as postnatal depression — always consider TFTs in new mothers with fatigue, mood changes, or unexplained physical symptoms.

📖 About

• Occurs within 12 months after delivery, often transient.
• Classically biphasic: hyperthyroidism → hypothyroidism → recovery.
• 20% of women who enter the hypothyroid phase develop permanent hypothyroidism.

🧬 Aetiology

• Autoimmune lymphocytic thyroiditis, often with anti-TPO antibodies.
• Increased risk with Type 1 diabetes, previous thyroid disease, autoimmune disorders.

🧫 Histology

• Lymphocytic infiltration of thyroid, mild follicular disruption.

🩺 Clinical Features

• Minimal thyroid enlargement, usually painless.
• Hyperthyroid phase: palpitations, tremor, anxiety, heat intolerance, weight loss.
• Hypothyroid phase: lethargy, cold intolerance, dry skin, weight gain, depression-like symptoms.

🔎 Investigations

• TFTs:
  • Hyperthyroid: ↑ T4, ↓ TSH
  • Hypothyroid: ↓ T4, ↑ TSH
• Anti-TPO antibodies: positive in most cases.

⚕️ Management

• Hyperthyroid phase: usually self-limiting. Beta-blockers for symptom relief; antithyroid drugs not required.
• Hypothyroid phase: T4 replacement if symptomatic or persistent; withdraw after 12 months to assess recovery.
• Monitoring: TFTs every 6–8 weeks until stable.
• Most recover within 12–18 months.

📋 Screening TFTs

Check thyroid function in high-risk groups:

• Atrial fibrillation
• Dyslipidaemia
• Type 1 diabetes, pregnancy, postpartum
• Amiodarone or lithium therapy (6-monthly)
• Down’s and Turner’s syndromes
• Addison’s disease

📊 Interpreting Thyroid Function Tests

💡 Interpretation pearl: In primary thyroid disease, TSH and T4 move in opposite directions. In central disease, TSH and T4 move in the same direction.

📚 Reference

• ATA: Postpartum Thyroiditis Patient Leaflet