Aspects That Will Be AddressedHyperthyroidismHypothyroidismThyroiditis

Causes of HyperthyroidismMost common causes

Graves diseaseToxic multinodular

goiterAutonomously

functioning nodule

Rarer causesThyroiditis or other

causes of destructionThyrotoxicosis factitiaStruma ovariiSecondary causes (TSH

or ßHCG)

Hyperthyroidism SymptomsHyperactivity/ irritability.Heat intolerance and sweating.Palpitations.Fatigue and weakness.Weight loss with increase of appetite.Diarrhoea.Polyuria.Oligomenorrhoea.Loss of libido

Hyperthyroidism SignsTachycardia (AF)Increased B.PTremorGoiterWarm moist skinProximal muscle

weaknessLid retraction or lagGynaecomastia Brisk tendon

reflexes

Graves DiseaseAutoimmune disorderAb directed against TSH receptor with

intrinsic activity. Thyroid and fibroblastsResponsible for 60-80% of ThyrotoxicosisMore common in women

Graves Disease Eye SignsN- no signs or symptomsO – only signs (lid retraction or

lag) no symptomsS – soft tissue involvement

(peri-orbital oedema)P – proptosis (>22 mm)(Hertl’s

test)E – extra ocular muscle

involvement (diplopia)C – corneal involvement

(keratitis)S – sight loss (compression of

the optic nerve)

Graves Disease Other Manifestations

Pretibial myxedema Thyroid acropachyOnycholysisThyroid enlargement

with a bruit frequently audible over the thyroid

Diagnosis of Graves DiseaseTSH , free T4 Thyroid auto

antibodies LATS,IF,Gastric

parietal cells.Nuclear thyroid

scintigraphy (I131, Tc99)

Treatment of Graves DiseaseReduce thyroid hormone production or

reduce the amount of thyroid tissueAntithyroid drugs: propylthiouracil,

carbimazoleRadioactiveiodineSubtotal thyroidectomy – relapse after

antithyroid therapy, young people.Symptomatic treatment

Propranolol.

Hypothyroidism SymptomsTiredness and

weaknessDry skinFeeling coldHair lossDifficulty in

concentrating and poor memory

Constipation

Weight gain with poor appetite

Hoarse voiceMenorrhagia, later

oligo and amenorrhoea

Paresthesias

Hypothyroidism SignsDry skin, cold extremitiesYellow tintPuffy face, hands and feetDelayed tendon reflex

relaxationCarpal tunnel syndrome BradycardiaIncreased B.PDiffuse alopeciaSerous cavity effusions

Causes of HypothyroidismAutoimmune

hypothyroidism (Hashimoto’s, atrophic thyroiditis)

Iatrogenic (I123 treatment, thyroidectomy, external irradiation of the neck)

Drugs: lithium, antithyroid drugs, etc

Iodine deficiencyInfiltrative disorders

of the thyroid: amyloidosis,

sarcoidosis, haemochromatosis.

Lab Investigations of Hypothyroidism

TSH , free T4 Ultrasound of thyroid – little valueThyroid scintigraphy – little valueAnti thyroid antibodies – anti-TPOSr.CK , Sr.Chol , Sr,Triglyseride Normochromic or macrocytic anemiaECG: Bradycardia with small QRS

complexes

Treatment of HypothyroidismLevothyroxine

If no residual thyroid function 1.5 μg/kg/dayPatients under age 60, without cardiac disease

can be started on 50 – 100 μg/day. Dose adjusted according to TSH levels

In elderly especially those with CAD the starting dose should be much less (12.5 – 25 μg/day)

ThyroiditisAcute: rare and due to suppurative infection

of the thyroidSub acute: also termed de Quervins

thyroiditis/ granulomatous thyroiditis – mostly viral origin

Chronic thyroiditis: mostly autoimmune (Hashimoto’s)

Acute ThyroiditisBacterial – Staph, StrepFungal – Aspergillus, Candida, Histoplasma,

PneumocystisRadiation thyroiditisAmiodarone (acute/ sub acute)Painful thyroid, ESR usually elevated, thyroid

function normal

Sub Acute ThyroiditisViral (granulomatous) – Mumps, coxsackie,

influenza, adeno and echovirusesMostly affects middle aged women, painful

enlarged thyroid, usually complete resolutionRx: NSAIDS and glucocorticoids if necessary

Sub Acute ThyroiditisSilent thyroiditis No tenderness of thyroidOccur mostly 3 – 6 months after pregnancy3 phases: hyperhyporesolution, last 12 to 20

weeksESR normal, TPO Ab presentUsually no treatment necessary

Chronic ThyroiditisHashimoto’s

AutoimmuneInitially goiter later very little thyroid tissueRarely associated with painInsidious onset and progressionMost common cause of hypothyroidismTPO ab present (90 – 95%)

Chronic ThyroiditisReidel’s

RareMiddle aged womenInsidious painlessSymptoms due to compressionDense fibrosis develop Usually no thyroid function impairment

ThyroiditisThe most common form of thyroiditis is

Hashimoto thyroiditis, this is also the most common cause of long term hypothyroidism

The outcome of all other types of thyroiditis is good with eventual return to normal thyroid function

CRETINISMImbecility.Idiocy.