Hypopituitarism

Question 1

Define hypopituitarism.

Answer 1

Hypopituitarism refers to the partial or complete deficiency of one or more pituitary hormones. It may arise as a congenital defect during the development of the pituitary gland or as a result of acquired diseases of the pituitary gland, the parasellar structures, or the hypothalamus.

Question 2

Explain the aetiology/risk factors of hypopituitarism.

Answer 2

Pituitary tumour
Pituitary apoplexy
Pituitary surgery
Cranial radiation
Traumatic brain injury
Genetic defects
Hypothalamic disease

Question 3

Summarise the epidemiology of hypopituitarism.

Answer 3

Hypopituitarism is relatively rare, with a prevalence of 45 cases per 100,000 and an incidence of about 4 cases per 100,000 per year in the normal population.

Question 4

Recognise the presenting symptoms of hypopituitarism. Recognise the signs of hypopituitarism on physical examination.

Answer 4

Presence of risk factors
Headaches
Failure to thrive or short stature
Infertility
Hypoglycaemia
Amenorrhoea/oligomenorrhoea
Galactorrhoea
Delayed puberty
Hypotension
Visual field defects
Ophthalmoplegia
Cardiovascular events
Cold intolerance
Weight gain
Erectile dysfunction and reduced libido
Nausea/vomiting
Fatigue
Weakness
Dizziness
Constipation
Dry skin
Delayed relaxation of reflexes

Question 5

Identify appropriate investigations for hypopituitarism and interpret the results.

Answer 5

Serum electrolytes
Serum and urine osmolarity
8 a.m. cortisol and adrenocorticotrophic hormone
Thyroid function tests
8 a.m. testosterone, follicle-stimulating hormone, and luteinising hormone in men
Oestradiol, follicle-stimulating hormone, and luteinising hormone in women
Prolactin
Insulin-like growth factor-1
Cosyntropin/tetracosactide stimulation test

Question 6

Generate a management plan for hypopituitarism.

Answer 6

Treat underlying cause. Treat pituitary apoplexy with IV hydrocortisone.

Question 7

Identify the possible complications of hypopituitarism and its management.

Answer 7

Male infertility
Female infertility
Corticosteroid over-replacement
Thyroxine over-replacement
Desmopressin over-replacement
Growth hormone over-replacement
Testosterone over-replacement

Question 8

Summarise the prognosis for patients with hypopituitarism.

Answer 8

Hypopituitarism has been associated with a 1.8-fold higher mortality compared with an age- and sex-matched population. Cardiovascular and cerebrovascular death rates are higher in patients with hypopituitarism compared with the normal population.