Pituitary and thyroid disease Flashcards
What is endocrine disease?
- Dysfunction of hormone secreting gland
What are the primary and secondary causes of endocrine disease?
Primary = GLAND failure (gland cannot make)
Secondary = CONTROL failure (gland can make but is not being asked to)
Do endocrine diseases have widespread, multisystem effect?
- Yes
what does MEN stand for?
- Multiple endocrine neoplasia
What does MEN 1 affect? (3 points)
- Parathyroid, Pancreatic Islets, Pituitary (anterior)
What are the associated tumours with MEN 1? (3 points)
- Adrenal cortex, Carcinoid, Lipoma
What does MEN 2a affect? (3 points)
- Parathyroid
- Medullary thyroid
- Phaeochromocytoma
What does MEN 2b affect? (4 points)
- MEdullary thyroid
- Phaeochromocytoma
- Mucosal neuromas (lump on nerve, on oral mucosa and tongue)
- Marfanoid appearance
What is Phaeochromocytoma?
- A tumour originating in cells of the adrenal gland that causes overproduction of certain hormones
What is Marfan syndrome?
A disorder of the body’s connective tissue, a group of tissues that maintain the structure of the body and support internal organs and other tissues
What does the pituitary do? (2 points)
- Control of many gland activities
- Hypothalamic control - releasing hormones
How is endocrine disease regulated?
Negative feedback regulation
What hormones are secreted by the anterior pituitary? (6 points)
- TSH (thyroid stimulating hormone)
- ACTH (adrenocorticotrophic hormone)
- GH (growth hormone)
- LH
- FSH
- Prolactin
What does ACTH stand for?
- Adrenocorticotrophic hormone
What hormones are secreted by the posterior pituitary? (2 points)
- ADH (Anti-diuretic hormone for diabetes insipidus)
- Oxytocin
Why are pituitary tumours usually caused by?
- Dysfunction from adenomas
Which hormones tend to be secreted in excess in a patient who is <40 and has a functional adenoma? (2 points)
- Prolactin
- ACTH
(Amenorrhoea-Galctorrhoea syndrome or Cushing’s syndrome)
What is Amenorrhoea-Galactorrhoea syndrome?
Unphysiological lactation of endocrinological origin or caused by a pituitary tumour
Which hormone tends to be secreted in excess in a patient who is >40 and has a functional adenoma? (2 points)
- Growth hormone
- Acromegaly
What is acromegaly?
- A rare condition resulting from excessive production of growth hormone by the pituitary gland
What does a non functional (space occupying) adenoma cause in patients over the age of 60? (2 points)
- Visual field defects
- Other hormone deficiencies
What is the Sella Turcica?
- A depression on the upper surface of the Sphenoid bone, lodging the pituitary gland
What is trans-sphenoidal surgery?
A surgical instrument is placed through the nostril and alongside the nasal septum to access the pituitary tumour
What does insufficient growth hormone in children cause?
Growth failure (reduced height - correct proportions but small)
What does insufficient growth hormone in adults cause? (2 points)
Metabolic changes in adults:
- Increased fat
- Reduced vitality
What does excessive growth hormone cause in children?
- ‘Gigantism’
What does excess growth hormone case in adults?
- Acromegaly
What is acromegaly?
- A rare condition where the body produces too much growth hormone, causing body tissues and bones to grow more quickly
- Over time, this leads to abnormally large hands and feet and a wide range of other symptoms
What do you measure to assess growth hormone?
- Measure IGF-1 (Insulin-like growth factor 1)
Acromegaly has insidious onset. What does this mean?
- It has a gradual or subtle development
At what age range is there a peak incidence of acromegaly?
- 30-50 years of age (can take 10-15 years till changes are obvious enough)
What can acromegaly be caused by?
A benign pituitary tumour - MEN-1 a possibility
What are common features of acromegaly? (6 points)
- Coarse features
- Enlarged supra-orbital ridges
- Broad nose, thickened lips & soft tissues
- Enlarged hands (carpal tunnel syndrome, finger numbness)
- Type 2 diabetes mellitus (insulin resistance from increased GH)
- CV disease (Ischaemic heart disease, acromegalic cardiomyopathy)
What are possible intraoral changes of a person with acrom egaly? (4 points)
- Enlarged tongue
- Interdental spacing
- ‘shrunk’ dentures
- Reverse overbite
Acromegaly can give a patient visual field defects. Which cranial nerves can have possible palsies as well? (3 points)
III, IV, VI
One possible feature of acromegaly is hyperprolactinaemia. What is this?
Higher than normal levels of prolactin in the body
Is one possible feature of acromegaly hypopituitarism?
- Yes
Is primary hyperthyroidism by a gland common or rar e?
Common
Is secondary hyperthyroidism as a result of loss of control of the process common or rare?
Rare
What is another word for hypothyroidism?
Myxoedema
Is the primary cause of hypothyroidism common or rare?
Common
Is the secondary cause of hypothyroidism common or rare?
- Less common than primary cause
What is Grave’s disease a form of?
Hyperthyroidism - 70%-80% of cases
- Autoantibodies stimulating the TSH receptor
What are 2 things that can cause hyperthyroidism?
- Toxic multi-nodular goitre
- Toxic adenoma
Can a pituitary tumour cause hyperthyroidism?
- Yes but this is rare (it is a secondary problem)
What is an effect of hyperthyroidism?
Increased metabolism
What are common symptoms of hyperthyroidism? (8 points)
- Hot & excess sweating
- Weight loss
- Diarrhoea
- Palpitations
- Muscle weakness
- Irritable, manic, anxious
What are common signs of hyperthyroidism? (5 points)
- Warm moist skin
- Tachycardia & atrial fibrillation
- Increased BP & heart failure
- Tremor & hypeerflexia
- Eyelid retraction & lid lag
If someone has Grave’s disease what do they usually have a family history of?
- Usually family history of autoimmune disease
- Vitiligo, PA, Type 1 DM, Coeliac, Myaesthenia gravis (if have one - more likely to have another)
Grave’s disease can cause ophthalmopathy. What is this?
Ocular changes:
- Scleral injection
- Proptosis
- Periorbital oedema
Grave’s disease can cause conjunctival oedema. What is another name for this and what is it?
- Chemosis
- Type of inflammation which occurs in the inner lining of the eyelid
What is scleral injection?
Red eyes, caused by enlarged, dilated blood vessels
What is proptosis?
Forward displacement or bulging of the eye
What is periorbital oedema?
Swelling in the area around the eyes
What are possible primary causes of hypothyroidism? (6 points)
- Autoimmune (Hashimoto’s) thyroiditis (90% of cases)
- Idiopathic atrophy
- Radioiodine treatment/thyroidectomy surgery
- Iodine deficiency
- Drugs (carbimazole, amiodarone, lithium)
- Congenital
What are possible secondary causes of hypothyroidism?
- Hypothalamic/pituitary disease
What effect does hypothyroidism have on the metabolism?
- Redced metabolism
What are common symptoms of hypothyroidism? (6 points)
- Tired
- Cold intolerance, weight gain, constipation
- Hoarse voice, goitre, puffed face & extremities
- Angina
- ‘slow’, poor memory
- Hair loss (common lateral 1/3 of eyebrow)
What are common signs of hypothyroidism? (5 points)
- Dry course skin
- Bradycardia, hyperlipidaemia
- Psychiatric or confusion
- Goitre (Hashimoto’s)
- Delayed reflexes
What age group and gender is usually affected by Hashimoto’s Thyroiditis?
- Middle aged and elderly women
What are the presenting features of Hashimoto’s disease? (2 points)
- Goitre
- Hypothyroid features
What is Hashimoto’s Thyroiditis associated with? (2 points)
- Often a family history of autoimmune disease
- Vitiligo, PA, Type 1 DM, Addison’s disease
- Downs syndrome
Is idiopathic atrophy more likely in males or females?
10x more likely in females
Does idiopathic atrophy incidence increase or decrease with age?
Increases
Idiopathic atrophy is likely an autoimmune cause. What dies this mean (2 points)
- Lymphocyte infiltrate
- Associated with organ specific autoimmune disease
How can you investigate thyroid disease via the blood?
By testing for TSH, T3 and T4
How can you investigate for thyroid disease via imaging? (2 points)
- Ultrasound scan (cysts)
- Radioisotope scans - gland uptake
How can you investigate for thyroid disease via tissues? (2 points)
- Fine needle aspirate/biopsy (FNA & FNB)
In hyperthyroid disease caused by a pituitary cause (rarer). What will the levels of TSH and T3 be?
- Raised TSH
- Raised T3
In hyperthyroid disease caused by a Grave’s or an adenoma (Common). What will the levels of TSH and T3 be?
- Low TSH
- Raised T3
(as autoantibody signalling)
In hypothyroid disease caused by a pituitary cause rarer). What will the levels of TSH and T4 be?
- Low TSH
- Low T4
In hypothyroid disease caused by gland failure (common). What will the levels of TSH and T4 be?
- High TSH
- Low T4
What are 2 drugs that can be used to treat hyperthyroidism?
- Carbimazole (titration, block and replace - T4 as required)
- Beta-blockers
Radioiodine can be used to treat hyperthyroidism. What is the problem with this?
- There is a hypothyroidism risk with time - review
What surgery option can be used to treat hyperthyroidism?
- Partial thyroidectomy
- Usually follows drug therapy to stabilise it
How can we treat Grave’s ophthalmopathy?
-none/simple measures
What is the treatment method for hypothyroidism? (3 points)
- Give T4 tablets (thyroxine) - slow response - weeks
- Increase dose slowly - IHD
- Recheck using TSH as a guide if gland failure
How does Goitre cause Thyroid enlargement? (4 points)
- Diffuse enlargement of the thyroid gland
- Often iodine deficient
- Diffuse, nodular
- Drug related?
How does Solitary nodule enlargement cause Thyroid enlargement? (2 points)
- Adenoma, carcinoma, cyst formation possible
- Low cancer risk - suspicious in children or elderly
Is there usually thyroid swelling when someone has thyroid cancer?
- Yes
What is thyroid cancer like in children?
Papillary (80%) or follicular in children
What is thyroid cancer like in adults?
- Undifferentiated in the elderly
What are the nodules like on radioisotope scans of thyroid cancer?
‘cold’
People with thyroid cancer are often TSH sensitive. What should they be given post surgery?
T4
What is the prognosis of thyroid cancer in the young?
- Generally good
- 5% 10 year mortality in papillary BUT
- 80% 10 year mortality in follicular
Is Goitre detectible to a dentist?
yes - if find it in an exam refer to GP immediately
How can patients with hyperthyroidism present in a dental setting?
- Pain, anxiety and psychiatric problems
Should you do dental treatment on patients who have untreated hyperthyroid?
- Caution for treatment until controlled
- Can do emergency treatment whilst waiting to settle
What should a dentist avoid the use of if a patient had severe (untreated) hyperthyroidism?
Avoid sedatives
If a patient has a thyroid problem but are on the correct treatment, should they be treated any different to a normal patient?
- No, they are normal
