endocrine

• Hypothalamus secretes

  •Thyrotropin-releasing hormone

  •Corticotropin-releasing home

  •Growth hormone-releasing hormone

  •Gonadotropin-releasing hormone

  •Dopamine

  •Vasopressin

  •Somatostatin

  Oxytocin

  
• pituitary gland

  A) TSH

  B) ACTH

  C) Prolactin

  D) GH

  E) FSH AND LH

  F) ADH

  G) Oxytocin

  H) Oxytocin

  
• thyroid gland

  
• Thyroid axis

  A) TRH

  B) TSH

  C) T3 and T4

  
• THYROID - - controls metabolic rate of tissues
• Hyperthyroidism symptoms

  A) Hair loss or thinning

  B) enlarged thyroid gland

  C) muscle weakness

  D) distrupted menstrual cycle

  E) heat sensitivity

  F) increased apetite

  G) sweating

  H) frequent bowel movements

  I) weight loss

  J) shaky hands

  K) heart palpitations

  L) difficulty sleeping

  M) Anxiety & nervousness

  
• Bloods for hyperthyroidism

  •TSH low

  •T3 high

  •T4 high
• Graves disease

  •Commonest cause of thyrotoxicosis

  •Women (2%), Men (0.2%)

  •Thyroid peroxidase (TPO) antibodies are present in about 75% of cases of Graves' hyperthyroidism

  •Eye changes – exophthalmos (proptosis of the eye), ophthalmoplegia, conjunctival oedema, papilloedema and keratopathy.

  
• Thyroid hormones

  •T4 inactive

  •T3 active  (activation occurs peripherally e.g. liver/kidney)

  •Most T3 and T4 bound to thyroglobulin in the blood

  •We tend to test T4 as it will become abnormal first

  
• Other causes of hyperthyroidism

  •Toxic nodular goitre

  •The presence of a multinodular goitre without the above symptoms (ie specific features of Graves' disease) suggests toxic nodular goitre (common in the elderly).
• Other causes of hyperthyroidism

  •Solitary thyroid nodule

  •Palpable, toxic adenoma.
• Other causes of hyperthyroidism

  •De Quervain's thyroiditis

  •Transient hyperthyroidism which probably results from a viral infection. Presents with features of hyperthyroidism with pyrexia and pain in the neck.
• Other causes of hyperthyroidism

  •Self-medication

  •This includes over-the-counter iodine supplements and 'energy-boosting' preparations containing thyroid hormones.
• Other causes of hyperthyroidism

  •Cancer

  •Associated with metastatic disease.
• Other causes of hyperthyroidism

  •Drugs

  •These include amiodarone, lithium and exogenous iodine.
• Thyroid Cancer most common

  A) papillary carcinoma

  B) follicular carcinoma

  C) medullary carcinoma

  
• Autoantibodies we test for in hyperthyroidism

  •TPO Abs

  •Anti-thyroglobulin Abs

  •TSH-receptor antibodies
• Other tests for hyperthyroidism

  •Thyroid US

  •Thyroid uptake scans
• Management - tablets - hyperthyroidism

  •Anti-thyroid medications (carbimazole, Propylthiouracil (PTU))

  •PTU to be used in pregnancy and thyroid storm

  •Carbimazole – must warn about sore throat. They need a FBC to check for bone marrow suppression.
• •Carbimazole – must warn about sore throat. They need a FBC to check for bone marrow suppression.
• •PTU to be used in pregnancy and thyroid storm
• Management – Radio-iodine - hyperthyroidism

  •Pts are given a drink

  •Destroys thyroid gland (can take up 3-4 months)

  •Must be avoided in pregnancy

  •Cleared through the urine – patients are asked to avoid contact with children and pregnant women

  •Complications: hypothyroidism
• Management – Surgery

  •Complications are hypothyroidism and other rare but include haemorrhage, hypoparathyroidism and vocal cord paralysis.
• Subclinical hyperthyroidism

  •Common, 2% of population

  •Low TSH but normal T3/T4

  •Normally not an issue unless patient is symptomatic (hyperthyroid sxs)
• Thyroid storm

  •Affects 1-2% of patients with hyperthyroidism

  •Exaggerated hyperthyroid sxs, mental disturbance and hyperthermia

  •Usually happens following surgery, radioiodine, meds change

  •Treatment is supportive with intravenous fluid, steroids and PTU

  •(Thyrotoxic periodic paralysis is another rare hyperthyroid event characterised by K shift into cells and associated paralysis)
• •Primary hypothyroidism

  •Autoimmune hypothyroidism - Hashimoto's thyroiditis (associated with a goitre) and atrophic thyroiditis.

  •Iatrogenic - radio-iodine treatment, surgery, radiotherapy to the neck - eg, lymphoma (no goitre usually).

  •Iodine deficiency - the most common cause worldwide and goitre is present.

  •Drugs - amiodarone, contrast media, iodides, lithium and antithyroid medication.

  •Congenital defects - eg, absence of thyroid gland or dyshormonogenesis.

  •Infiltration of the thyroid - eg, amyloidosis, sarcoidosis and haemochromatosis.
• •Secondary hypothyroidism

  •Isolated TSH deficiency.

  •Hypopituitarism - neoplasm, infiltrative, infection and radiotherapy.

  •Hypothalamic disorders - neoplasms and trauma.
• Hypothyroidism symptoms

  A) memory decline

  B) dry skin

  C) constipation

  D) irregular heavy period's

  E) joint muscle aches

  F) cold intolerance

  G) weight gain

  H) fatigue

  I) depression

  
• Hashimotos - autoimmune i hypothyroidism

  •Has a painless goitre
• Atrophic thyroiditis - hypothyroidism

  •No goitre
• Treatment for hypothyroidism

  •Levothyroxine
• Subclinical hypothyroidism

  •High TSH but normal T3/T4

  •Important to repeat. Only relevant if patient has symptoms of hypothyroidism
• Hypoadrenalism

  •Primary – Addison’s(UK most common, TB( most common worldwide)

  •Secondary – issue with pituitary

  
• Hypoadrenalism symptoms

  •Chronic:

  Fatigue and weakness (common feature), Anorexia, Nausea, Vomiting, Weight loss, Abdominal pain, Diarrhoea, Constipation, Cravings for salt and salty foods such as soy sauce or liquorice (primary insufficiency), Muscle cramps and joint pains, Syncope or dizziness (due to hypotension), Confusion, Personality change, Irritability, Loss of pubic or axillary hair in women, delayed puberty in children.
• Hypoadrenalism symptoms

  •Acute

  Hypotension, hypovolaemic shock, acute abdominal pain, low-grade fever and vomiting. Sudden onset of insufficiency, such as the Waterhouse-Friderichsen syndrome (infarction secondary to septicaemia - eg, meningococcal) presents with collapse and shock.
• Addison’s presents with hyperpigmentation

  
• Hyperpigmentation

  •look at buccal mucosa, lips, palmar creases, new scars and in areas subject to pressure such as elbows, knuckles and knees.

  •This is not present in secondary adrenal insufficiency as it is related to ACTH

  
• Hyperpigmentation

  •ACTH is produced from pro-opiomelanocortin (POMC) which also produce alpha-melanocyte stimulating hormone,

  •In primary adrenal insufficiency the hypothalamus and pituitary glands produce high amounts of POMC and ACTH - and melanocyte-stimulating hormone as a by-product

  
• Addison’s

  •Autoimmune – antibiodies against adrenal cortex

  •ACTH rises as cortisol levels drop

  •Associated with other autoimmune conditions (thyroid, diabetes, pernicious anaemia)
• Tests for hypoadrenalism

  •Na, K, Glucose,

  •Serum 9am cortisol

  •Short Synacthen test

  •Serum ACTH (differentiate between primary and secondary causes)

  •Renin-aldosterone will give an indication of mineralocorticoid activity

  •Consider pituitary imaging if ACTH felt to be issue