Pituitary Disease

Question 1

Classify the different types of pituitary adenomas?

Answer 1

Microadenoma less than 10mm

Macroadenoma greater than 10mm

Also classified by their endocrine function: In decreasing order of prevalence:

• Non-functioning adenomas (hypopituitarism)
• Prolactinomas
• Growth hormone (GH)-secreting
• Adrenocorticotrophic hormone (ACTH)-secreting
• Thyroid-stimulating hormone (TSH)-secreting
• Leutinising hormone/follicle-stimulating hormone (LH/FSH)-secreting tumours

Question 2

Describe the local symptoms resulting from a large pituitary macroadenoma?

Answer 2

Peri-orbital headaches.

Visual field loss: bi-temporal hemianopia.

Ocular nn palsy causing a squint.

If it extends into the hypothalamus it could dysregulation of: appetite, thirst, temperature regulation and consciousness.

Question 3

Outline the systemic clinical consequences of a non functioning pituitary adenoma?

Answer 3

Panhypopituitarism

Least importants for life lost 1st:

LH, GH, TSH, and lastly ACTH and FSH

Presentation in adults tends to be:

• Infertility oligo/amenorrhoea, erectile dysfunction.
• Deficiency Decreased muscle bulk, decreased body hair, central obesity and small, soft testes.
• Hypothyroid symptoms

Question 4

Outline the clinical features of functioning pituitary adenomas?

Answer 4

Functioning tumours can cause:

• Hyperprolactinaemia (lactation, ammenorrhoea, gynaecomastia, erectile dysfunction, decreased body hair)
• Acromegaly
• Hyperthyroidism
• Cushings

Question 5

What are the potential causes of hypothalmic pituitary disturbances?

Answer 5

Kallmann’s (anosmia + GnRH deficiency) ƒ

Hypothalamic: tumour, inflammation, infection or ischaemia

Infiltration: Haemochromaosis, amyloidosis

Question 6

Outline how you would investigate pituitary disease?

Answer 6

Visual field test.

Hormones:

LH/FSH, Prolactin, GH, TFTs, cortisol/ACTH

Head CT/MRI

Question 7

Describe the treatment options of Prolactinomas?

Answer 7

They are benign tumors and therefore only treat if:

• Symptoms due to tumor size
• Symptoms due to endocrine disturbance
• 90% of the time they are microadenomas

Treatment:

1st line is treatment with dopamine agonists which lower prolactin levels as dopamine has an inhibitory effect on prolactin release. (prolactinoma’s are the most common secretory tumour)