5 Thyroid cases Simon Pearce RVI, Endocrine Unit Unusual Thyroxine Requirement • 39 year old woman • Congenital hypothyroidism • Required up to 200µcg thyroxine daily in childhood and adolescence • High TSH despite high thyroxine dose – Date – 5/01 – 8/02 – 10/02 – 1/03 TSH 11.3 16.0 13.3 17.7 Daily T4 dose 200µcg 250µcg 300µcg 400µcg What to do now? • Talk about compliance – Should involve some mention of LT4 half-life • Explore drug interactions – Ferrous salts – Calcium carbonate (eg. calcichew, rennie) – Gaviscon etc. – PPIs – Cholestryamine etc. • Think about malabsorption (Coeliac Abs) Actions • Prescribe dosette box • Re-iterate taking thyroxine before breakfast on an empty stomach • Suggest that thyroxine taken at bedtime • Review 8 weeks to recheck TSH • Remember, they’re probably not taking their other medication either Next steps • Refer • Peak dosage effects (tachy, headache) – Suggest split dose (eg. 50 mcg bd) – Try thyroxine liquid solution • Supervised dosing – Eg. 1000 mcg once per week • Thyroxine absorption test Palpitations • 79 year old woman • Palpitations • Weight loss • Sinus rhythm • TSH <0.05 • FT4 18.0 (0.3-4.7 mU/l) (9.5-21.5 pmol/l) • 79 year old woman • Palpitations • Weight loss • Sinus rhythm • TSH <0.05 • FT4 18.0 • FT3 9.4 (0.3-4.7 mU/l) (9.5-21.5 pmol/l) (3.5-6.5 pmol/l) What to do now? Actions • Prescribe beta blocker – Eg. Propranolol LA 80 mg od or bd • Refer • Indications for urgent referral – Atrial fibrillation – Worsening angina – Heart failure • Consider starting Carbimazole 20mg od or bd – Need to warn about agranulocytosis risk Next steps • For mild-moderate Graves’ disease – Carbimazole therapy – Block & replace for 12 months • Discuss radioiodine therapy with patient – Permanent hypothyroidism risk (50% or 95%) – Short-term radiation protection measures (11 d) – No cancer risk, no fertility risk, no alopecia • In the case of AF, angina, heart failure: – Warfarin – Early RAI – May cover with carbimazole for 4-6 months post RAI Oh Baby! • 34 year old woman • On thyroxine for 12 years for hypothyroidism • Period 10 days late • Boots pregnancy test positive • Stopped thyroxine yesterday, worried about effect of drugs on her baby • Second pregnancy; miscarriage at 10 weeks in first pregnancy • Last recorded TSH 6 months ago = 3.9 mU/l What to do now? Actions • Check TSH urgently • Recommend increase dose LT4 of 25 mcg/d pending TSH result • Explain fetal thyroid hormone synthesis doesn’t start until 10-12 years • Thyroxine critical for brain development • Thyroxine is the same as natural thyroid hormone Next steps • Low or suppressed TSH is normal in first trimester • 4 to 8 weekly TFT monitoring throughout pregnancy • Increased thyroxine dose very likely • Refer joint medical obstetric clinic Lump in my neck • 28 year old F • Sister noticed neck lump last week • No pain • O/e – Anterior triangle neck lump 4x4 cm What to do now? Actions • Ask about alarm features: – Airway compromise – Voice change • Check TSH • Refer (endocrine, endocrine surgery, ENT) • We will generally see within 2 weeks • We will see urgently if alarm features Next steps New onset anterior triangle lump Check TSH & refer FNA cytology Management decision If surgery, symptoms etc. then imaging I’m tired and emotional • • • • 45 year old woman Feels tired Daytime somnolence Forgetfulness & emotional lability • TSH 6.2 mU/l • Hb 13.5 g/l • RBG 5.9 mmol/l What to do now? Actions • Recheck TSH, with FT4 & TPO antibodies • Assess symptoms • If TSH persistently elevated, discuss trial of thyroxine therapy • Close to full replacement dose (75 or 100mcg/d) for 3 or 4 months • Continue if symptoms are improved Next steps • Symptoms are worse on thyroxine – ? Addison’s disease – ? Hypopituitary • Consider other diagnoses – – – – – – Depression, mood disturbance, alcohol etc. Sleep apnoea Vitamin D deficiency Iron deficiency B12 deficiency Many other possibilities