Endocrinology

Question 1

What are anterior and posterior hormones?

Answer 1

1. LH/FSH
2. TSH
3. ACTH
4. GH
5. Prolactin
6. Vasopressin
7. Oxytocin

Question 2

How is growth hormone produced and how does it function?

Answer 2

 Secreted in pulses  Amount secreted per day much
higher in children than adults
 Stimulates growth and cell division in childhood
 Effects mediated by IGF-1
 Other reported effects:  Decreased body fat  Increased muscle mass  Increased bone density  Increased energy levels  Improved skin tone
 Improved immune system function

Question 3

What is acromegaly?

Answer 3

Adult onset - growth hormone excess after the completion of linear growth
Overgrowth of soft tissues In children – gigantism
Pituitary adenoma – GH secreting cells Usually benign

Question 4

What are the clinical features of acromegaly?

Answer 4

Sweating Skin change  Snoring  Arthritis Carpal tunnel syndrome
 Headache Visual Changes
Change in hand and foot size
Ask about rings and shoes
Change in teeth Change in appearance
‘coarse features’
 Amenorrhoea  Impotence

Question 5

What are the signs of acromegaly?

Answer 5

Macroglossia
Prognathism
Increased inter-dental spacing
Soft tissue enlargement
Hypertension Diabetes Sleep apnoea
Bitemporal hemianopia

Question 6

What are the investigations and diagnosis of acromegaly?

Answer 6

Confirm the presence of growth hormone excess
IGF-1 elevated Abnormal GH response e.g. lack of suppression on OGTT Measure other pituitary hormones
Then find the source with MRI pituitary Visual fields

Question 7

What are the treatment options of acromegaly?

Answer 7

 Gold standard = pituitary surgery
 1. Dopamine agonist therapy
 Relatively low response rates
 2. Somatostatin analogues  Long acting (monthly) available  ~£6000 - £13,000 per annum
 3. Pegvisomant (GH receptor antagonist)  Blocks GH action
 ~£18,000 - £50,000 per annum  SEs rare - reversible hepatitis (~1%)
 4. RT

Question 8

What’s the relevance of acromegaly to dentistry?

Answer 8

Pt complains of trouble with teeth  Increased interdental spacing  Dentures may not fit  Macroglossia
Snoring Change in appearance – coarse features Insidious onset

Question 9

What’s the Hypothalamic Pituitary Adrenal Axis (ACTH)? (Cushing’s syndrome).

Answer 9

Essential for life
Cortisol:
Involved in response to stress and anxiety
Increases Bp (vascular tone) and blood sugar
Affects the immune response
Axis abnormal in depression, stress, severe illness etc.
The hypothalamus sends messages to the anterior pituitary gland which sends messages to the adrenal cortex to release cortisol (circadian rhythm of cortisol release)

Question 10

What is Cushing’s syndrome?

Answer 10

Excess cortisol  Pituitary adenoma
 ACTH secreting cells (Cushing’s disease)
 Adrenal tumour: adenoma or carcinoma
 Ectopic ACTH production  Bronchial NET, small cell lung cancer, more weird rare
stuff..
 Iatrogenic  Excess steroid

Question 11

What are the clinical features of Cushing’s disease?

Answer 11

 Change in appearance  Abdominal adiposity  Muscle wasting in limbs
 Thin skin  Easy bruising  Acne  Hirsuitism  Poor wound healing
 Diabetes  Hypertension
 Lemon-on-sticks appearance
 Moon face  Buffalo hump  Osteoporosis
 Psychiatric illness  Euphoria  Depression  Psychosis

Question 12

What’s the investigation and screening for Cushing’s?

Answer 12

Screening 24 hour urinary free cortisol
Further tests involve confirming the diagnosis and the site of excess hormone production
Imaging of adrenals (CT) or pituitary (MRI) depending on results

Question 13

What’s the management for Cushing’s?

Answer 13

Referral to an Endocrinologist
Temporary medical control of hormone excess?
Surgical resection of the lesion adrenalectomy
transphenoidal hypophysectomy Nasty disease, difficult to cure long-term
Patient may be on steroid replacement post- operatively…

Question 14

What’s the relevance of Cushing’s to dentistry?

Answer 14

Poor wound healing, thin skin, easy bruising
Psychiatric manifestations
Immunocompromised - may be more prone to infection
Complex if on replacement steroids after treatment…
Look out for moon face…although some people look cushingoid but aren’t!

Question 15

What’s hypoadrenalism?

Answer 15

Loss of glucocorticoid production Possible loss of mineralocorticoid production
Primary: adrenal (Addison’s Disease)
Secondary: pituitary disease
Iatrogenic: pts on long term steroid who stop suddenly
Important role in maintaining circulating volume and blood pressure

Question 16

What are the clinical features of Addison’s disease?

Answer 16

 Non-specific complaints of malaise, tiredness and weakness
 Weight loss  Abdominal pain  Vomiting
 Postural hypotension  May have increased
pigmentation
 Can be associated with other autoimmune diseases e.g. hypothyroidism, type 1 diabetes, vitiligo
Twice age related mortality Equivalent to smoking

Question 17

What’s the investigation and diagnosis of Addison’s disease?

Answer 17

Short synacthen test with ACTH measurement

Question 18

What’s the management of Addison’s disease?

Answer 18

Glucocorticoid replacement  Cortisol deficiency  Hydrocortisone 10mg/5mg/5mg  Cortisone acetate/Prednisolone/Dexamethasone
Mineralocorticoid replacement  Aldosterone deficiency  Fludrocortisone 100mcg
Secondary insufficiency  Review all other pituitary hormones

Question 19

In times of stress what levels of glucocorticoid doses should be given?

Answer 19

 Inter-current illness
 Double normal oral dose
 Wean to normal 48hours post recovery
 Will need iv/im if significant vomiting and/or diarrhoea and unable to absorb tablets
 Steroid emergency pack
Peri-post-operative period:
Procedure dependent
Local anaesthetic: ?double dose on morning of procedure
GA: iv steroids required peri-op and while nbm

Question 20

How should you manage patients on long term steroid therapy?

Answer 20

Common scenario with potential for adverse outcome…
Will look cushingoid but will be unable to mount an adequate response to stress
Do not stop steroid treatment suddenly May well need increased steroid cover for procedures

Question 21

What’s the relevance of Addison’s disease to dentistry?

Answer 21

Look for characteristic pigmentation on gums and buccal mucosa
Onset often insidious and vague
Patients may need increased steroid cover for procedures
A major operation on a patient with undiagnosed adrenal insufficiency may precipitate an ‘Addisonian crisis’ with circulatory collapse

Question 22

What’s T3 and T4 used for? (it’s released by the thyroid gland and is essential for life)

Answer 22

T4 and T3: Increase metabolic rate in all cells Regulate cell O2 use and heat generation
In adults also play a role in protein, fat and CHO metabolism, nerve function, muscle function, bone health, skin health and reproductive function
In fetus and neonate, thyroid hormones are responsible
for growth & development of all tissues including brain

Question 23

What are the commonest causes of hyperthyroidism/ Thyrotoxicosis

Answer 23

 Graves’ disease  Autoimmune  Associated with eye disease  Often young and female
 Toxic multinodular goitre  Commoner in older patients  May have an obvious goitre

Question 24

What are the clinical symptoms of hyperthyroidism?

Answer 24

 Weight loss  Increased appetite  Heat intolerance  Irritability  Diarrhoea  Amenorrhoea  Change in hair and skin
 Swelling in neck
 Eye symptoms  Prominence  Dryness  Pain
 Grittiness  Tiredness  Palpitations
 Fine tremor  Warm clammy palms  Lid retraction, proptosis  Chemosis  Sinus tachycardia or atrial fibrillation
 Goitre  May have stridor  May have dysphagia

Question 25

What are the investigations and diagnosis of hyperthyroidism?

Answer 25

 Biochemistry Suppressed TSH elevated free T4 and free T3

 Imaging Ultrasound scan: nodule(s) Isotope scan – diffuse or nodular upake

Question 26

What’s the management of hyperthyroidism?

Answer 26

 Medical  Anti-thyroid medication - Carbimazole or Propylthiouracil  Side effect - Agranulocytosis
 Radio-Iodine  Safety guidelines
 Patient perceptions  Pregnancy plans
 Surgery Failure of medical treatment Compressive symptoms Patient choice

Question 27

What’s the relevance of hyperthyroidism to dentistry?

Answer 27

Very common Pathology may be visible in head and neck
Uncontrolled patients at risk of a ‘thyroid storm’ peri-operatively
Agranulocytosis/neutropenia as a side effect of the medication
 Often manifests as mouth ulcers or sore throat –ask about it!
 Stop medication and urgent full blood cou

Question 28

What causes hypothyroidism?

Answer 28

Primary hypothyroidism – autoimmune
Following treatment for hyperthyroidism  Medical overtreatment  Radioiodine  Surgery
Secondary to pituitary disease

Question 29

What are the clinical features of hypothyroidism?

Answer 29

 Weight gain  Cold intolerance  Tiredness  Constipation  Menorrhagia  Thinning Hair  Women > men
 Puffy face
 Macroglossia (rarely)
 Goitre
 Bradycardia
 Loss of outer third of eyebrow
 Slow relaxing reflexes

Question 30

What’s the investigation and diagnosis of hypothyroidism?

Answer 30

Biochemistry  High TSH with low/normal free T4 and low/normal free T3
No imaging necessary

Question 31

What’s the treatment of hypothyroidism?

Answer 31

 Typically lifelong hormone replacement  Levothyroxine at about 1.5mcg/kg  Average dose 100mcg od

Question 32

What’s the relevance of hypothyroidism to dentistry?

Answer 32

Very common
No need to change doses around time of procedures
Defer procedures if untreated or significantly undertreated
Absorption of Thyroxine  Drugs  Calcium, iron supplements  Caffeine, Soya milk…