The Pituitary Gland - Clinical Cases and Discussion

Question 1

Describe normal pituitary anatomy.

Answer 1

• Pea-sized
• Sits in the sella turcica of the sphenoid bone (the bottom of which is called the hypophyseal fossa)
• Has an anterior and posterior lobe, which are separated by the pars intermedia
• Sits directly beneath the optic chiasm

Question 2

Describe neuroendocrine control of pituitary secretion.

Answer 2

a

Question 3

Discuss the clinical presentation of the pituitary hyperfunction syndrome, acromegaly.

Answer 3

Soft tissue overgrowth;

• ‘Spade like’ hands (rings)
• wide feet (shoes)
• Coarse facial features
• Thick lips & tongue
• Carpal tunnel syndrome
• Sweating

Question 4

Discuss the clinical presentation of the pituitary hyperfunction syndrome, Cushing’s disease.

Answer 4

High value;

• Skin atrophy
• Spontaneous purpura
• Proximal myopathy
• Osteoporosis
• Growth arrest in children

Intermediate value;

• Pink striae
• Facial mooning and hirsutism
• Oedema

Non-specific;

• Central obesity
• Hypertension

Question 5

Discuss the clinical presentation of the pituitary hyperfunction syndrome, prolactinoma.

Answer 5

a

Question 6

Discuss the biochemical diagnosis of the pituitary hyperfunction syndrome, acromegaly.

Answer 6

REPLACE THESE ANSWERS

Can GH be supressed?
Is IGF-1 elevated?
Is the rest of pituitary function normal?
Is there a pituitary tumour on MRI?
Is vision normal?

Question 7

Discuss the biochemical diagnosis of the pituitary hyperfunction syndrome, Cushing’s disease.

Answer 7

a

Question 8

Discuss the biochemical diagnosis of the pituitary hyperfunction syndrome, prolactinoma.

Answer 8

a

Question 9

Describe the clinical features of hypopituitarism in adults and children.

Answer 9

a

Question 10

Discuss the concept of neoplasms of the endocrine system as being functional (i.e. secreting hormones) and non-functional (i.e. non-secretory).

Answer 10

a

Question 11

Discuss the concept of neoplasms being benign and malignant, in the context of the endocrine system.

Answer 11

a

Question 12

Describe the consequences of a space-occupying lesion in the pituitary region (imaging techniques, visual field assessment).

Answer 12

a

Question 13

Discuss the clinical management of patients with pituitary disease (pituitary surgery, radiotherapy, medical therapy and pituitary hormone replacement).

Answer 13

a

Question 14

Discuss the complications of the pituitary hyperfunction syndrome, acromegaly.

Answer 14

• Headache
• Chiasmal compression
• Diabetes mellitus
• Hypertension
• Cardiomyopathy
• Sleep apnoea
• Accelerated OA
• Colonic polyps & CA

Question 15

Explain the effect of excess cortisol on tissue, sodium and insulin and what diseases this could cause.

Answer 15

Excess cortisol = Cushing’s syndrome.

Tissue breakdown causes weakness of skin, muscle & bone.

Sodium retention may cause hypertension & heart failure.

Insulin antagonism may cause diabetes mellitus.

Question 16

Name the causes of Cushing’s syndrome/disease.

Answer 16

Not all cases of Cushing’s syndrome are due to a pituitary tumour.

ACTH-dependent;

• Pituitary tumour i.e. Cushing’s DISEASE
• Ectopic ACTH secretion e.g. lung carcinoid

ACTH-independent;

• Adrenal tumour e.g. adenoma or carcinoma
• Corticosteroid therapy e.g. for asthma, IBD.

Question 17

What is the difference between Cushing’s syndrome and disease?

Answer 17

Cushing’s disease;

• AKA secondary hypercortisolism
• Often caused by a pituitary tumour
• Results in production of ACTH, which stimulates excess cortisol production

Cushing’s syndrome;

• AKA primary hypercortisolism
• Often due to causes outside of the body e.g. corticosteroid therapy
• Results in excess cortisol