Simon Pearce 5 Thyroid cases 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 –DateTSHDaily T4 dose –5/ µcg –8/ µcg –10/ µcg –1/ µcg

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 mcg once per week Thyroxine absorption test

Palpitations

79 year old woman Palpitations Weight loss Sinus rhythm TSH <0.05( mU/l) FT4 18.0( pmol/l)

79 year old woman Palpitations Weight loss Sinus rhythm TSH <0.05( mU/l) FT4 18.0( pmol/l) FT3 9.4( 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 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