Overview
Confirm Graves autoimmunity, select antithyroid or definitive treatment with reproductive safeguards, and identify thyroid eye disease requiring urgent sight-saving specialist care.
Graves disease results from stimulating autoantibodies at the TSH receptor. The thyroid component usually produces diffuse hyperfunction, while orbital fibroblast inflammation and glycosaminoglycan deposition cause thyroid eye disease. The two components can follow different time courses: eye disease may occur during euthyroidism or after thyroid treatment, so a normal thyroid profile does not dismiss new ophthalmic symptoms.
Initial hyperthyroidism management combines symptom control, restoration of euthyroidism and a plan for remission or definitive therapy. Antithyroid drugs avoid immediate gland destruction but can relapse and have rare serious toxicity. Radioiodine is convenient for suitable non-pregnant adults but leads commonly to hypothyroidism and can exacerbate eye disease. Total thyroidectomy gives rapid definitive control but requires an experienced surgeon and carries hypocalcaemia, nerve and operative risks.
Eye management is organised by threat, activity and severity. Mild exposure symptoms may respond to preservative-free lubrication, nocturnal ointment, head elevation and thyroid stabilisation. Moderate-to-severe active disease requires a joint ophthalmology-endocrinology service for immunomodulatory treatment. Optic neuropathy and corneal breakdown are emergencies where visual outcome depends on rapid specialist treatment rather than routine endocrine follow-up.
Aetiology
TSH-receptor autoimmunity
Stimulating autoantibodies activate thyroid TSH receptors, producing diffuse hormone synthesis and gland growth despite suppressed pituitary TSH.
Orbital autoimmune involvement
Related immune activity targets orbital fibroblasts, with inflammation and glycosaminoglycan accumulation affecting extraocular muscles and orbital soft tissues.
Clinical modifiers
Smoking, unstable thyroid status and treatment transitions can influence eye-disease activity, so thyroid and ophthalmic courses do not always move together.
Pathophysiology
- 1Thyroid receptors are stimulated
Autoantibodies drive new thyroid hormone synthesis and diffuse gland activity independently of normal hypothalamic-pituitary feedback as the process continues.
- 2Adrenergic and metabolic effects develop
Excess hormone increases heat production, heart rate, gut activity and tissue catabolism, causing tremor, weight loss, palpitations and weakness.
- 3Orbital tissues expand
Inflammation, oedema and glycosaminoglycan deposition enlarge muscles and fat within the fixed bony orbit, causing proptosis, diplopia and exposure.
- 4Sight may become threatened
Severe swelling can compress the optic nerve or prevent corneal protection, producing an ophthalmic emergency even when thyroid tests are controlled.
Clinical features and red flags
Diffuse smooth enlargement, bruit, tremor, warm skin, tachycardia and proximal weakness support Graves; pretibial dermopathy and acropachy are specific but uncommon extrathyroidal signs.
Grittiness, photophobia, tearing, retro-orbital discomfort, conjunctival redness, lid swelling and pain with eye movement suggest orbital inflammation even before marked proptosis.
Restrictive diplopia, impaired elevation or abduction, troublesome proptosis, exposure symptoms and inability to work or drive because of visual disturbance merit prompt specialist thyroid-eye assessment.
Reduced central or colour vision, new visual-field defect, relative afferent pupillary abnormality or optic-disc change can result from apical compression, sometimes without dramatic proptosis.
Lagophthalmos, severe pain, photophobia, epithelial defect, ulceration or a cloudy dry cornea indicates exposure-related threat and requires immediate ocular protection plus same-day ophthalmology.
Recurrent palpitations and weight loss after a medicine course suggests relapse; fever, sore throat, mouth ulcer, jaundice or severe abdominal pain while taking carbimazole instead raises an adverse-drug emergency.
Investigations
- 01
TSH, free T4 and free T3First step - Why
- Establish severity and follow biochemical response to treatment.
- Interpretation and limitations
- Suppressed TSH with raised peripheral hormone confirms overt thyrotoxicosis; early monitoring should follow free hormones because TSH may remain suppressed after control improves.
- 02
TSH-receptor antibodies - Why
- Confirm Graves autoimmunity and inform selected reproductive or relapse questions.
- Interpretation and limitations
- Positive TRAb supports Graves. Negative results do not absolutely exclude it; NICE suggests technetium scintigraphy when diagnostic uncertainty remains and imaging is safe.
- 03
Baseline full blood count and liver tests - Why
- Assess suitability and create a reference before antithyroid treatment.
- Interpretation and limitations
- Unexpected neutropenia or significant hepatic dysfunction needs endocrine or haematology discussion; subsequent testing is symptom-triggered rather than routine in an asymptomatic patient.
- 04
Structured eye examination - Why
- Detect exposure, motility restriction and optic nerve dysfunction at presentation.
- Interpretation and limitations
- Document acuity, colour desaturation, pupils, fields by confrontation, ocular movements, diplopia, lid closure and corneal staining; any optic or corneal threat needs same-day review.
Differential diagnosis
Toxic nodular disease
An irregular nodular gland with patchy or focal uptake and absent Graves eye signs suggests autonomous nodules rather than diffuse receptor autoimmunity.
Destructive thyroiditis
Painful or painless release of stored hormone produces low uptake and does not respond mechanistically to antithyroid synthesis blockade.
Orbital cellulitis
Fever, severe unilateral pain and infective orbital signs favour cellulitis, which needs urgent antimicrobial and ophthalmic assessment.
Other orbital mass
Marked asymmetry, atypical progression or a discrete imaging lesion suggests tumour or inflammation unrelated to Graves disease.
Management
01New GravesConfirm and stabilise hyperthyroidismFirst stepClinical and biochemical findings suggest Graves disease without storm.+
- 1Measure TRAb, document cardiac and eye status, check pregnancy possibility and obtain baseline full blood count and liver tests before thionamide treatment.
- 2Use BNF-checked carbimazole and symptom control under the local pathway, with explicit infection, liver, pancreatitis and reproductive safety-netting.
- 3DefinitiveMonitor free hormones initially, then discuss a 12-to-18-month medicine course or definitive radioiodine or surgery according to relapse risk and patient priorities.
02Eye triageProtect sight before grading cosmeticsAny eye symptom occurs in current or previous Graves disease.+
- 1Check acuity, colour vision, pupils, visual fields, motility, diplopia, lid closure and corneal integrity, comparing both eyes and documenting change.
Complications
Thyrotoxic cardiac disease
Persistent hormone excess can cause atrial fibrillation, heart failure and ischaemic stress, particularly in older patients or those with underlying cardiac disease.
Dysthyroid optic neuropathy
Apical orbital crowding can compress the optic nerve, causing colour desaturation, field loss and permanent visual impairment without rapid specialist treatment.
Corneal breakdown
Proptosis and incomplete lid closure expose the cornea, leading to ulceration, infection and sight loss when lubrication and closure are inadequate.
Monitoring and follow-up
- Follow free T4 and free T3 during early antithyroid titration, allowing for delayed TSH recovery and adjusting only through the agreed treatment strategy.
- At every contact ask about fever, sore throat, mouth ulcers, bruising, jaundice, pruritus, dark urine and severe abdominal pain while carbimazole continues.
- Document visual acuity, colour perception, diplopia, corneal symptoms and lid closure over time; advise immediate review for any rapid deterioration.
- Record smoking status and offer evidence-based cessation support repeatedly, as stopping remains a disease-modifying intervention for the orbit.
- After antithyroid withdrawal, provide relapse symptoms and scheduled thyroid tests; after radioiodine or total thyroidectomy, monitor for and replace expected hypothyroidism.
- Review contraception and conception timing at each relevant visit, because medicine and radioiodine plans can become unsafe when circumstances change.
Special situations
Orbit and thyroid can diverge
Eye inflammation may begin or worsen when biochemical status is normal, so new visual symptoms deserve examination rather than reassurance from a recent TSH.
Activity differs from severity
Redness, swelling and pain describe inflammatory activity; diplopia, exposure and optic-nerve compromise describe impact. Both dimensions guide specialist treatment.
Proptosis is not the sight test
Apical muscle crowding can damage the optic nerve with modest forward displacement. Colour desaturation, acuity, pupils and fields are higher-value danger checks.
Radioiodine needs orbital context
Eye activity, smoking and other risk factors influence whether radioiodine is appropriate and whether specialist glucocorticoid cover is considered.
TRAb can outlive the gland
Antibodies can persist after surgery or radioiodine and cross the placenta, so previous definitive treatment does not remove pregnancy-related antibody assessment.
Common pitfalls
- 01
Describing every prominent eye as cosmetic without testing vision, colour and cornea.
- 02
Using TSH alone for early carbimazole titration while it remains suppressed.
- 03
Continuing carbimazole through fever and sore throat without urgent blood count.
- 04
Offering radioiodine without asking about active eye disease, smoking and pregnancy plans.
- 05
Assuming a normal thyroid profile excludes active orbital inflammation.
- 06
Using systemic glucocorticoids for eye disease without a specialist cumulative-dose and safety protocol.
- 07
Stopping antithyroid treatment abruptly in pregnancy without immediate expert advice.