Endocrine Flashcards
benign tumour name
malignant name as well
adenoma
carcinoma
autoimmune gland stimulation disease
Graves’ disease is an immune system disorder that results in the overproduction of thyroid hormones (hyperthyroidism).
mechanisms of endocrine disease
- Autoimmune destruction – e.g. Type 1 diabetes, Addison’s disease, primary hypothyroidism
- Other destruction – e.g. surgery, cancer, TB.
- Autoimmune stimulation – Grave’s hyperthyroidism
- Tumour formation – benign (adenoma), malignant (carcinoma).
- Effects of tumours – mechanical due to tumour mass; excess hormone production.
clinical management of endocrine diseases
- Management of steroid replacement during dental treatment (separate lecture)
- Acromegaly – can present with malocclusion, changing denture fit, TMJ arthritis. Facial signs, tongue and lips.
- Addison’s disease – buccal pigmentation.
- Recognition of syndromes from facial appearance – pictures may occur in exams.
- Parathyroid disease – bone disease may affect jaws/teeth
hyperthyroidism -
- what is is
- what causes it
- features
- investigation
- treatment
Excess production of thyroxine (T4) and tri-iodothyronine (T3).
Causes Graves disease (autoimmune stimulation of TSH receptor on thyroid cells). Thyroid adenoma, multinodular goitre. Excess TSH from pituitary is very rare (unlike ACTH). Thyroid cancer presents as thyroid swelling, not thyrotoxicosis.
Features – Sped up metabolism and adrenergic excess; weight loss, feeling hot, increased appetite, sometimes increased energy, diarrhoea, tremor, tachycardia, atrial fibrillation, sweating. Goitre – swollen thyroid, which moves on swallowing.
Graves disease – causes exopthalmos with lid retraction or lid lag. Can affect eye movements – diplopia. Can be severe.
Investigation – increased T4 and T3 with suppressed TSH. Thyroid stimulating antibodies in Graves. Thyroid scans.
Treatment – beta blockers to control adrenergic symptoms, especially tachycardia. Antithyroid drugs – carbimazole and propylthiouracil. Radioactive iodine. Surgical removal of thyroid adenoma or multinodular goitre.
hypothyroidism
- what is is
- what causes it
- features
- investigation
- treatment
Lack of T4 and T3. ‘Myxoedema’ is an old synonym, but strictly applies to the infiltration of tissues with proteinaceous fluid that is part of the condition.
Causes – autoimmune destruction of thyroid. After-effects of radio-iodine for hyperthyroidism. Surgery to thyroid gland. Occasionally secondary to pituitary failure.
Features – slowing down of metabolism: weight gain, feeling cold, reduced appetite, lethargy, constipation, slow pulse, dry skin. Myxoedema causes puffy features with periorbital swelling, croaky voice. Also may have goitre.
Investigation – low T4 and T3, high TSH. Thyroid autoantibodies.
Treatment – thyroxine replacement.
Addison’s disease
- what is is
- what causes it
- features
- investigation
- treatment
Due to deficiency of adrenal cortical steroids – cortisol and aldosterone.
Causes – true Addison’s disease is autoimmune destruction (sometimes associated with pernicious anaemia or vitiligo). Adrenals can also be attacked by cancer, TB and surgeons – hypoadrenalism, but not true Addison’s. Hypopituitarism results in cortisol lack, along with other hormones.
Features – tiredness, weight loss. Hyperpigmentation, including buccal, due to excess ACTH, a by-product of which stimulates melanocytes. Addisonian Crisis – severe hypotension, dehydration, electrolyte disturbances, hypoglycaemia, vomiting.
Investigation – low levels of cortisol. ACTH increased. Adrenal antibodies.
Treatment – 1. Replacement of hormones with hydrocortisone (=cortisol) and fludrocortisone (synthetic aldosterone agonist). 2. Crisis – medical emergency requiring intravenous saline, glucose and hydrocortisone. 3. Prevention of crisis – ensure increased steroids during severe illness/infection. Patient education.
Cushing syndrome
- what is is
- what causes it
- features
- investigation
- treatment
Due to excess cortisol or other glucocorticosteroids.
Causes Commonest is iatrogenic due to steroid treatment of other conditions; this suppresses adrenals and impairs native steroid production, so patients become dependent on exogenous steroid during illness or stress. ‘Natural’ causes - pituitary adenoma secreting ACTH; adrenal tumour secreting cortisol – adenoma or carcinoma.
Features Change in body shape – moon face, buffalo hump, abdominal obesity, proximal limb muscle wasting. Thin skin, abdominal striae, bruising. Hirsutism (due to adrenal androgens in women). Glucose intolerance, diabetes (insulin resistance). Psychological changes. Hypertension (mineralocorticoids causing salt and water retention). Pituitary tumour effects – headache, bitemporal hemianopia.
Investigation – increased blood and urine cortisol levels. Failure to suppress with dexamethasone (artificial steroid which feeds back on hypothalamus and suppresses ACTH). Direct ACTH measurement. Imaging of pituitary or adrenal.
Treatment - usually surgical removal of pituitary or adrenal tumour
Primary Hyperparathyroidism
- what is is
- what causes it
- features
- investigation
- treatment
Hypercalcaemia due to (usually) adenoma of parathyroids secreting excess PTH.
Features – often asymptomatic. ‘Stones, bones, abdominal groans and psychic moans’. Kidney stones (calcium); bone cysts, ‘brown tumours’, subperiosteal resorption; constipation, dyspepsia, pancreatitis; confusion, depression. Thirst and polyuria due to inability to concentrate urine.
Cause – usually a parathyroid adenoma.
Investigation – raised calcium with high PTH (which should be suppressed if calcium is high). Parathyroid scan.
Treatment – surgical removal.
Hypoparathyroidism
Hypocalcaemia – causes tingling and tetany due to excitability of nerves and muscles. Autoimmune or complication of thyroid surgery. Treated by active vitamin D analogues and calcium supplemments (PTH replacement not available).
