Pituitary Gland Pathology

Question 1

Location

Answer 1

Inferior to the hypothalamus

Question 2

Anterior Pituitary

Answer 2

Adenohypophysis

Derived from Rathke;s pouch

Secretes trophic and non-trophic hormones

Question 3

Trophic Hormones

Answer 3

TSH
ACTH
FSH
LH

Question 4

Non-trophic hormones

Answer 4

GH

Prolactin

Question 5

Posterior Pituitary

Answer 5

Neurohypophysis

Extension of neural tissue consists of modified glial cells and axonal processes

Secretes ADH (vasopressin) and oxytocin

Question 6

Anterior Pituitary (Histology + Hormones)

Answer 6

Islands, cord of cells

Acidophils

• somatotrops =GH
• mammotrophs= Prolactin

Basophils

• corticotrophins = ACTH
• thyrootrophs = TSH
• gonadotrophs = FSH/ LH

Chromophobe

Question 7

Posterior Pituitary (Histology)

Answer 7

Non-myelinated axons of neurosecretory neurons

Question 8

Anterior Pituitary Hyperfunction aetiology

Answer 8

Adenoma

Carcinoma

Question 9

Anterior Pituitary Hypofunction aetiology

Answer 9

Surgery/radiation 
Sudden haemorrhage into gland 
Ischaemic necrosis 
Tumours extending into sella 
Inflammatory conditions

Question 10

Posterior Pituitary Common pathology

Answer 10

Diabetes Insipidus

• Lack of ADH secretion
• can lead to life-threatening dehydration

SIADH

• ectopic secretion of ADh by tumours
• primary disorder in pituitary

Question 11

Pituitary adenoma

Answer 11

Derived from cells of anterior pituitary

Sporadic or associated with MEN1

Question 12

Micro vs macro adenomas

Answer 12

Microadenomas <1cm

Macroadenomas >1cm

Question 13

Classification of pituitary adenomas

Answer 13

Classified by cell type/ hormone produced 
- prolactin 
-ACTH
-FSH/LH
- GH
(Can produce more than one hormone0

Question 14

large pituitary adenoma consequences

Answer 14

Visual field defects

pressure atrophy of surrounding normal tissue

Question 15

Functional Pituitary Adenomas

Answer 15

Prolactinoma

Growth Hormone Secreting

ACTH secreting

Question 16

pituitary Hypofunction

Answer 16

Usually panhypopituitarism
- rarely affects individual hormones

many causes

Question 17

Craniopharyngioma

Answer 17

Derived from remnants of Rathkes pouch

Slow growing, often cystic, may calcify

most are suprasella

headaches and visual disturbances

Excellent prognosis (esp <5cm)

Question 18

Diabetes Insipidus Aetiology

Answer 18

Posterior pituitary syndrome

Central

• ADH deficiency
• Trauma, tumours and inflammatory disorders of hypothalamus and pituitary

nephrogenic
- Renal resistance to ADH

Question 19

SIADH aetiology

Answer 19

Posterior pituitary syndrome

Ectopic production of ADH
- Paraneoplastic syndrome