Thyroid

Cormac Joyce

November 21st 2008

Thyroid

Causes of solitary thyroid nodule:o Prominent nodule in MNGo Cysto Follicular adenomao Carcinomao Thyroiditis

Thyroiditis

Inflammation of thyroid glandCauseso Hashimotoso De Quervains

Hashimotos

Chronic Lymphocytic ThyroiditisThyroid always enlarged TSH, ↓T4, Thyroid Abs present in 90%HypothyroidismRx: Eltroxin

De Quervains

Rapidly swollen and painful glandLarge amounts of thyroid hormoan

produced= hyperthyroidismMost resolve completely within weeksSome become hypothyroid after

Diffusely enlarged thyroid

Simple Colloid GoitreGraves diseaseThyroiditis

Colloid Goitre

Causes Increased physiological demand• Puberty• Pregnancy• Lactation Iodine deficiency Carbimazole

Graves Disease

Abs v TSH receptorHyperthyroidism +/- thyrotoxicosisIx: Low TSH High T3 and T4 TSH receptor Abs

Graves Disease

Featureso Eye Signs specific to Graves Lid retraction: Dalrymples sign Lid Lag Exophthalmos Chemosis Ophthalmoplegia Optic atrophy Corneal ulcerationo Pretibial myxoedema: non pitting oedema

Adenoma

Usually follicularCannot distinguish from follicualr Ca on

FNASurgery to confirm Dx

Thyroid Ca

PapillaryFollicularMedullaryAnaplasticLymphomaMets

TMNG

Second most common cause of thyrotoxicosis after Graves

Plummers disease Single toxic adenoma

Hyperthyroid features

Heat intolerance Palmar erythema Tremor Weight loss Onychyolysis (Plummers nails) – ragged nail

bed edges Increased appetite Tachycardia +/- A Fib Graves: eye signs + pretib myxoedema + thyroid

acropachy

Ix of Thyroid Disease

Low TSH, High T3 and T4Antibodies: Anti TSH Abs: Graves Anti Thyroid peroxidase: Hashimotos

Ix of Thyroid Disease

Nuclear Medicine Scan Cold nodule: could be Ca Hot nodule: unlikely to be Ca• US +/- FNA Distinguish solid v cystic

Hyperthyroid Treatment

Medical Thyrostatics: Propylthyrouracil,

Carbimazole Beta BlockersRadioactive Iodine131 Can cause hypothyroidism

Thyroid Surgery

Indications Malignancy Obstruction: Pembertons sign, dilated

neck veins, Thoracic inlet obstruction Thyrotoxicosis Cosmesis Retrosternal expansion

Thyroid Ca

Papillary 80% Young patients Spreads to LNs Can be treated with Lobectomy or total

thyroidectomt

Thyroid Ca

Follicular 8% Average age 50 years FNA not useful Haematogenous spread Rx: total thyroidectomy and replacement

therapy and radioiodine ablation

Thyroid Ca

Medullary 7% Parafollicular cells secrete calcitonin 10% familial: MEN II, 90% sporadic Rx: thyroidectomy and calcitonin follow up

Thyroid Ca

Anaplastic 5% Occurs in elderly Usually T4 on presentation Rx: debulking and XRT

Cx of Thyroid Surgery

Haematoma RLN palsy SLN palsy Hypoparathyroidism and hypocalcaemia Thyroid storm: pre, intra or post op Prevented by PTU 10/7 pre op Hypothyroidism Infection Keloid scar

Varicose Veins

Pathophysiology

Intima and media of vein invaded by fibrous tissue, so venous tone is lost

Valves become incompetent

Veins Involved

Long Saphenouso Arises anterior to MM, travels on lateral

aspect of leg and joins SFJ 2cm below and lateral

Short Saphenous