Hyposecretion Of Pituitary Hormones

Question 1

Explain the difference classifications of endocrine diseases and define hypopituitarism

Answer 1

Problems with anterior pituitary gland - secondary endocrine gland disease
Problems with the endocrine gland - primary endocrine gland disease

Hypopituitarism: decreased production of all anterior pituitary hormones (congenital/ acquired) sometimes called pan hypopituitarism

Question 2

Describe congenital pant hypopituitarism

Answer 2

Rare, usually due to mutations of transcription factors needed for normal anterior Pituitary development (eg PROP 1: deficient in GH and another hormone, causes short stature, hypoplastic (gland not developed))

Question 3

Describe the causes of acquired pan hypopituitarism (specifically simmonds, Sheehan’s, pituitary apoplexy)

Answer 3

Causes: tumours, radiation, infection, traumatic brain injury, infiltrative disease, inflammation, pituitary apoplexy, peri partum infarction

Simmonds: symptoms due to deficiency of hormones. FSH/ LH: secondary hypogonadism (reduced sex hormones - reduced libido, secondary amenorrhea, erectile dysfunction ), ACTH: secondary hypoadrenalism (cortisol deficiency - fatigue), TSH : secondary hypothyroidism (fatigue)

Sheehans syndrome: when anterior pituitary gland enlarges during pregnancy due to lactotroph hyperplasia but you have a post partum haemorrhage (PPH) and hypopituitarism due to hypotension (pitutary infarction), causes symptoms of lethargy, anorexia, weight loss, failure of lactation, failure of resume of menses post delivery.

Pituitary apoplexy: intra pituitary haemorrhage (or infarction), often dramatic presentation in patients with pre-existing pituitary tumours, can be precipitated by anticoagulants (severe sudden onset headaches, visual field defect and compressed optic chiasm )

Question 4

Describe the method of diagnosis of hypopituitarism

Answer 4

Biochemical: 1. Basal plasma concentration of pituitary or target endocrine gland, but no good because cortisol fluctuates time of day. 2. Stimulated combined function test - induce hypoglycaemia (via insulin) to stimulate GH and ACTH release 3. Radiography - pituitary MRI may reveal specific pituitary pathology eg haemorrhage, adenoma,

Question 5

Describe the hormone replacement therapies for hypopituitarism

Answer 5

1. ACTH > hydrocortisone (check for cortisol)
2. TSH > thyroxine (check free T4)
3. LH/FSH > women :HRT (E2 and progesterone) (check symptom improvements) Men: testosterone
4. GH > GH (check IGF1 and growth chart for kids)

Question 6

Describe the causes of growth hormone deficiency

Answer 6

Genetic, environment, malnutrition, malabsorption, endocrine

Prader Willi: GH deficiency
Dwarfism: achondroplasia

Diagnosis:

Look at notes for treatment and IGFI crap