AKT · Endocrine/Thyroidlow yield

Thyroiditis

Inflammatory thyroid hormone release (subacute/De Quervain, postpartum, Hashimoto)

Overview

Inflammation of the thyroid causing a release of preformed hormone — a transient thyrotoxic phase, then often hypothyroid, then recovery. Types: subacute (De Quervain, post-viral, painful), postpartum (painless), and Hashimoto (autoimmune, usually hypothyroid). Key point: LOW radioiodine uptake — treat the thyrotoxic phase with a beta-blocker, not antithyroid drugs.

Recognise

Subacute (De Quervain): PAINFUL, tender goitre after a viral illness, fever, raised ESR; self-limiting
Postpartum/silent: PAINLESS thyrotoxicosis then hypothyroidism within a year of delivery
Classic triphasic course: thyrotoxic → hypothyroid → euthyroid; LOW radioiodine uptake

Red flags

Distinguish from Graves (high uptake) — antithyroid drugs are inappropriate in thyroiditis
Persisting hypothyroidism (esp. Hashimoto/postpartum) may need levothyroxine

Differentials & how to tell them apart

Graves diseaseHIGH diffuse uptake, TRAb positive, eye signs — not self-limiting

Toxic nodular goitrehot nodules, nodular gland

Thyroid cancer (painful)a hard fixed nodule rather than diffuse tender swelling

Investigations

TFTs (thyrotoxic then hypothyroid), LOW radioiodine uptake, raised ESR/CRP (subacute), anti-TPO (Hashimoto/postpartum). Ultrasound if needed.

Management

Beta-blocker (± NSAID/steroid for pain); levothyroxine if hypothyroid

1Recognise the self-limiting triphasic course with LOW uptake. Thyrotoxic phase: beta-blocker (and NSAID/steroid for the painful subacute form). Monitor through the hypothyroid phase.Gate: Do NOT give antithyroid drugs — the gland is releasing stored hormone, not over-synthesising; low uptake distinguishes it from Graves
2Levothyroxine for a symptomatic/persistent hypothyroid phase; postpartum thyroiditis may recur and can become permanent.

Beta-blocker (thyrotoxic phase) — symptom control — NOT antithyroid drugs (no excess synthesis)

NSAIDs / short steroid course (subacute) — for the painful goitre

Levothyroxine — for the hypothyroid phase if symptomatic/persistent

Key points

Painful tender goitre post-virus + low uptake + raised ESR = De Quervain. Painless thyrotoxicosis after delivery = postpartum thyroiditis. Either way: beta-blocker, not carbimazole.

Monitor & prognosis

TFTs through the phases; watch for permanent hypothyroidism.

Usually self-limiting; some become permanently hypothyroid.

Source: CKS; British Thyroid Association