Thyroid diseaseThyroid disease

Nazif PerwezJoy Coles

GPST2 - Oct 2010

Nazif PerwezJoy Coles

GPST2 - Oct 2010

Primary HyperthyroidismPrimary Hyperthyroidism

90% of cases are due to: Grave's disease toxic nodular goitre:

multinodular single toxic nodule - usually an adenoma

Other common causes: thyroiditis

de Quervain's silent / post-partum Hashimoto's - hashitoxicosis may develop mid-course

Uncommon: intentional / factitious overenthusiastic therapy drug-induced Jod - Basedow transient - neonatal

90% of cases are due to: Grave's disease toxic nodular goitre:

multinodular single toxic nodule - usually an adenoma

Other common causes: thyroiditis

de Quervain's silent / post-partum Hashimoto's - hashitoxicosis may develop mid-course

Uncommon: intentional / factitious overenthusiastic therapy drug-induced Jod - Basedow transient - neonatal

Secondary Hyperthyroidism

Secondary Hyperthyroidism

Hyperthyroidism as a result of pathology in another organ which causes excess stimulation of the thyroid gland.

Excess TSH:

uncommon: TSH secreting pituitary adenoma pituitary stimulation due to excessive hypothalamic release

of TRH

rare: hydatidiform moles choriocarcinoma embryonal testicular carcinoma

Extraneous thyroid hormone - all rare: struma ovarii - ovarian teratoma with thyroid tissue metastatic, well differentiated thyroid carcinoma

Hyperthyroidism as a result of pathology in another organ which causes excess stimulation of the thyroid gland.

Excess TSH:

uncommon: TSH secreting pituitary adenoma pituitary stimulation due to excessive hypothalamic release

of TRH

rare: hydatidiform moles choriocarcinoma embryonal testicular carcinoma

Extraneous thyroid hormone - all rare: struma ovarii - ovarian teratoma with thyroid tissue metastatic, well differentiated thyroid carcinoma

Differential DiagnosesDifferential Diagnoses

anxiety states: differentiation may be difficult clinically positive findings for thyrotoxicosis are eye signs,

proximal myopathy, wasting, hyperdynamic circulation with warm peripheries

anxiety tends to cause clammy hands

phaeochromocytoma: especially if the patient is hypertensive

anxiety states: differentiation may be difficult clinically positive findings for thyrotoxicosis are eye signs,

proximal myopathy, wasting, hyperdynamic circulation with warm peripheries

anxiety tends to cause clammy hands

phaeochromocytoma: especially if the patient is hypertensive

TFTsTFTs

T3 and T4 determination

TSH determination - normal serum TSH concentration nearly always excludes the diagnosis of thyrotoxicosis; the rare exceptions to this are a TSH-producing pituitary tumour or thyroid hormone resistance syndrome.

TRH stimulation test (rarely performed)

radioisotope iodine scanning

serology

T3 and T4 determination

TSH determination - normal serum TSH concentration nearly always excludes the diagnosis of thyrotoxicosis; the rare exceptions to this are a TSH-producing pituitary tumour or thyroid hormone resistance syndrome.

TRH stimulation test (rarely performed)

radioisotope iodine scanning

serology

Other testsOther tests

FBC: normochromic normocytic anaemia may be

seen in Graves' disease

ESR: raised in Graves' disease high in subacute thyroiditis

Calcium - often raised

LFTs - may be abnormal in Graves' disease

FBC: normochromic normocytic anaemia may be

seen in Graves' disease

ESR: raised in Graves' disease high in subacute thyroiditis

Calcium - often raised

LFTs - may be abnormal in Graves' disease

MANAGEMENTMANAGEMENT Admit if the person has severe signs and symptoms

of hyperthyroidism (e.g. fever, agitation, heart failure, confusion, or coma) or is systemically unwell.

Otherwise, refer all other individuals with overt hyperthyroidism for specialist management. The need for treatment should be based on the degree of elevation of serum free thyroxine (FT4) and free triiodothyronine (FT3) and clinical symptoms and signs as well as the cause of hyperthyroidism: The decision to initiate treatment with a

thionamide (carbimazole or propylthiouracil) in primary care should be made under specialist advice.

Consider a beta-blocker for symptomatic treatment or if a contraindicated, seek specialist advice regarding alternative drug treatment (e.g. diltiazem).

Admit if the person has severe signs and symptoms of hyperthyroidism (e.g. fever, agitation, heart failure, confusion, or coma) or is systemically unwell.

Otherwise, refer all other individuals with overt hyperthyroidism for specialist management. The need for treatment should be based on the degree of elevation of serum free thyroxine (FT4) and free triiodothyronine (FT3) and clinical symptoms and signs as well as the cause of hyperthyroidism: The decision to initiate treatment with a

thionamide (carbimazole or propylthiouracil) in primary care should be made under specialist advice.

Consider a beta-blocker for symptomatic treatment or if a contraindicated, seek specialist advice regarding alternative drug treatment (e.g. diltiazem).

HypothyroidismHypothyroidism

Primary hypothyroidism

Common: chronic autoimmune thyroiditis Hashimoto's disease following thyroidectomy or radioiodine treatment iodine deficiency or, rarely, gross excess drug-induced de Quervain's thyroiditis - usually transient silent thyroiditis - usually transient; may be permanent

Uncommon: post-external beam irradiation to the neck congenital causes infiltrative disease:

sarcoidosis systemic amyloidosis

Primary hypothyroidism

Common: chronic autoimmune thyroiditis Hashimoto's disease following thyroidectomy or radioiodine treatment iodine deficiency or, rarely, gross excess drug-induced de Quervain's thyroiditis - usually transient silent thyroiditis - usually transient; may be permanent

Uncommon: post-external beam irradiation to the neck congenital causes infiltrative disease:

sarcoidosis systemic amyloidosis

Secondary HypothyroidismSecondary Hypothyroidism

Uncommon and is usually caused by: panhypopituitarism hypothalamic lesion with isolated TSH deficiency

Uncommon and is usually caused by: panhypopituitarism hypothalamic lesion with isolated TSH deficiency

ManagementManagement

Treat overt hypothyroidism with levothyroxine.

All people who are stable on levothyroxine require at least annual measurement of serum thyroid-stimulating hormone (TSH): To check compliance To ensure that the dosage is still correct

Treat overt hypothyroidism with levothyroxine.

All people who are stable on levothyroxine require at least annual measurement of serum thyroid-stimulating hormone (TSH): To check compliance To ensure that the dosage is still correct

Ongoing managementOngoing management Aim to achieve a serum thyroid-stimulating

hormone (TSH) concentration that is within the reference range (0.4–4.5 mU/L).

In the elderly, younger people and those with IHD start with small dose (25-50mcg) and titrate at 2-3 month intervals with 25-50mcg steps

Measure TSH and free thyroxine (FT4) 2–3 months after each change in dose of levothyroxine.

Most people have a normal serum TSH concentration on a maintenance dose of 75–150 micrograms of levothyroxine daily.

Aim to achieve a serum thyroid-stimulating hormone (TSH) concentration that is within the reference range (0.4–4.5 mU/L).

In the elderly, younger people and those with IHD start with small dose (25-50mcg) and titrate at 2-3 month intervals with 25-50mcg steps

Measure TSH and free thyroxine (FT4) 2–3 months after each change in dose of levothyroxine.

Most people have a normal serum TSH concentration on a maintenance dose of 75–150 micrograms of levothyroxine daily.

When to refer- HypothyroidismWhen to refer-

Hypothyroidism Secondary hypothyroidism is suspected (refer urgently). Subacute Thyroiditis(de Quervain's thyroiditis) is suspected. Hypothyroidism is thought to be due toend organ resistance. They are younger than 16 years of age. They are pregnant or postpartum. They have particular management problems (e.g. ischaemic

heart disease, or being treated with amiodarone or lithium). They feel worse during treatment, as they may have

undiagnosed adrenal disease. They have continuing symptoms after appropriate thyroxine

treatment (i.e. thyroid function tests are now within the reference ranges) to investigate for a non-thyroid cause of the symptoms

Secondary hypothyroidism is suspected (refer urgently). Subacute Thyroiditis(de Quervain's thyroiditis) is suspected. Hypothyroidism is thought to be due toend organ resistance. They are younger than 16 years of age. They are pregnant or postpartum. They have particular management problems (e.g. ischaemic

heart disease, or being treated with amiodarone or lithium). They feel worse during treatment, as they may have

undiagnosed adrenal disease. They have continuing symptoms after appropriate thyroxine

treatment (i.e. thyroid function tests are now within the reference ranges) to investigate for a non-thyroid cause of the symptoms

Case study 1Case study 1

Monday morning 72 year old living independently and rarely comes to the

doctors. She had lost her purse on three occasions within the last fortnight and her son had arrived for his monthly visit on Monday to find she thought it was a Sunday and was upset that her cat was missing (the cat had died 2 years ago).

He has brought her to you today. The patient appears upset in surgery that due to a misunderstanding she has had to miss church and come to the surgery. She is apologetic for using up your spare time. Her main complaint is her eyes which feel sore and watery and she says she is getting breathless going up the stairs.

Monday morning 72 year old living independently and rarely comes to the

doctors. She had lost her purse on three occasions within the last fortnight and her son had arrived for his monthly visit on Monday to find she thought it was a Sunday and was upset that her cat was missing (the cat had died 2 years ago).

He has brought her to you today. The patient appears upset in surgery that due to a misunderstanding she has had to miss church and come to the surgery. She is apologetic for using up your spare time. Her main complaint is her eyes which feel sore and watery and she says she is getting breathless going up the stairs.

On examination she has a pulse of 90 which is irregular. She has sparse bibasal creps on auscultation of the chest. Her urine dip is negative and the remainder of the examination is unremarkeable. Her eyes are reddened. Her BMI is 18 and you notice that her wedding ring is loose on her finger. BP is 180/100

On examination she has a pulse of 90 which is irregular. She has sparse bibasal creps on auscultation of the chest. Her urine dip is negative and the remainder of the examination is unremarkeable. Her eyes are reddened. Her BMI is 18 and you notice that her wedding ring is loose on her finger. BP is 180/100

The son is ok to stay with her for a fortnight and neither are keen for a hospital admission.

Thyroid function tests come back within the day as

T4 27, TSH 0.01. She is given: Carbimazole 20mg od (pt has low BMI) Aspirin Lubricating eye drops Refer to endocrinologist

The son is ok to stay with her for a fortnight and neither are keen for a hospital admission.

Thyroid function tests come back within the day as

T4 27, TSH 0.01. She is given: Carbimazole 20mg od (pt has low BMI) Aspirin Lubricating eye drops Refer to endocrinologist

Son wants to know how long it will take for mother to be able to be left alone again.

Son asks about side effects of ‘toxic’ medication.

Son wants to know how long it will take for mother to be able to be left alone again.

Son asks about side effects of ‘toxic’ medication.

In the older population, thyroid disease can present in different ways – confusion which is not acute in onset and vague constitutional symptoms. In any acute confusional state it is reasonable that if you do not have an obvious cause, to do thyroid function tests.

In the older population, thyroid disease can present in different ways – confusion which is not acute in onset and vague constitutional symptoms. In any acute confusional state it is reasonable that if you do not have an obvious cause, to do thyroid function tests.

Thyroid eye disease (exclusive to Grave’s disease) leaves patients with sore watery eyes and can be severe enough to restrict the eye movements and cause discomfort with eye movements. This may be helped with a course of high dose steroids and may require surgery but in less severe cases, a bottle of hypromellose is all that is required to provide comfort.

Thyroid eye disease (exclusive to Grave’s disease) leaves patients with sore watery eyes and can be severe enough to restrict the eye movements and cause discomfort with eye movements. This may be helped with a course of high dose steroids and may require surgery but in less severe cases, a bottle of hypromellose is all that is required to provide comfort.

Case Study 2Case Study 2

36 yr old, presents with palpitations, lethargy and sore throat , worse on swallowing for 2 days. This was preceded by a cold with a cough but she feels she is getting worse and now getting hot and cold sweats. Routine examination reveals no abnormality in the ears, nose or throat and mild pyrexia of 37.9.

What else would you check?

36 yr old, presents with palpitations, lethargy and sore throat , worse on swallowing for 2 days. This was preceded by a cold with a cough but she feels she is getting worse and now getting hot and cold sweats. Routine examination reveals no abnormality in the ears, nose or throat and mild pyrexia of 37.9.

What else would you check?

Neck glands…… Tender anterior neck, worse on swallowing. There is no palpable goitre

Pulse…… Rate 110 ?related to fever

Neck glands…… Tender anterior neck, worse on swallowing. There is no palpable goitre

Pulse…… Rate 110 ?related to fever

deQuervains thryroiditis – uncommon post viral inflammation of thyroid gland. There may or may not be a palpable goitre but the thyroid gland will be tender. The patient will have symptoms of hyperthyroidism at the outset and this is accompanied by a pyrexia.

The condition is self limiting (within months) and usually follows course of hyperthyroidism, hypothyroidism then euthyroidism. Due to viral cause, no antibiotics are indicated and treatment options include NSAIDs, prednisolone and beta blockers for symptom control.

Refer endocrinologist for monitoring.

deQuervains thryroiditis – uncommon post viral inflammation of thyroid gland. There may or may not be a palpable goitre but the thyroid gland will be tender. The patient will have symptoms of hyperthyroidism at the outset and this is accompanied by a pyrexia.

The condition is self limiting (within months) and usually follows course of hyperthyroidism, hypothyroidism then euthyroidism. Due to viral cause, no antibiotics are indicated and treatment options include NSAIDs, prednisolone and beta blockers for symptom control.

Refer endocrinologist for monitoring.

Case Study 3Case Study 3

9 year old boy with lump in the neck approx pea sized. Non tender. No other symptoms.

On examination lump is on left side of thyroid glandDo you a. Reassure?b. Check TFTs?c. Arrange ultrasound and fine needle aspiration

cytology?d. Refer to Thyroid surgeon?

9 year old boy with lump in the neck approx pea sized. Non tender. No other symptoms.

On examination lump is on left side of thyroid glandDo you a. Reassure?b. Check TFTs?c. Arrange ultrasound and fine needle aspiration

cytology?d. Refer to Thyroid surgeon?

Answer is d. This patient fulfils the 2-week urgent cancer referral for head and neck.

Answer is d. This patient fulfils the 2-week urgent cancer referral for head and neck.

A Thyroid swelling associated with any one of the following:

A Thyroid swelling associated with any one of the following:

A solitary nodule increasing in size A history of neck irradiation A family history of an endocrine

tumour Unexplained hoarseness or voice

changes Very young (pre-pubertal) patient Patient aged 65 years and older

A solitary nodule increasing in size A history of neck irradiation A family history of an endocrine

tumour Unexplained hoarseness or voice

changes Very young (pre-pubertal) patient Patient aged 65 years and older

The reason why you do no other tests before referral is that this may cause unnecessary delay to the patient’s diagnosis and treatment. Once the 2-week rule cancer referral has been received the department can organise any scans or tests much faster than you would be able to in primary care.

The reason why you do no other tests before referral is that this may cause unnecessary delay to the patient’s diagnosis and treatment. Once the 2-week rule cancer referral has been received the department can organise any scans or tests much faster than you would be able to in primary care.