The Pituitary Gland Clinical Case & Discussion Flashcards
What causes the vast majority of hypersecretive pituitary disorders?
Pituitary tumours
In hypersecretive pituitary disorders, what are the three hormones which are affected in acromegaly, Cushing’s and hyperprolactinaemia?
Acromegaly - GH
Cushing’s - ACTH
Hyperprolactinaemia - Prolactin
Which of the posterior pituitary diseases can be involved in a hyposecreting disorder?
Vasopressin
What are some clinical features of acromegaly?
Spade like hands Wide feet Coarse facial features Thick lips and tongue Carpal tunnel syndrome Sweating
What should be considered when diagnosing acromegaly?
Can the GH be suppressed? Is IGF-1 elevated? Is the rest of the pituitary function normal? Is there a pituitary tumour on the MRI? Is vision normal?
In basic terms what causes Cushing’s syndrome?
Excess corticosteroids
What are the consequences of cushing’s syndrome?
Tissue breakdown - weakness of skin, muscle and bone
Sodium retention - may cause HTN and HF
Insulin antagonism - may cause DM
What are some symptoms of high value in Cushing’s disease?
Skin atrophy Spontaneous pupura Proximal myopathy Osteoporosis Growth arrest in children
What two classifications may Cushing’s disease be in relation to ACTH?
ACTH-dependant
ACTH-independant
What are the causes of ACTH-dependant Cushing’s syndrome?
Pituitary tumour - Cushing’s DISEASE
Ectopic ACTH secretion e.g. lung carcinoid
What are the causes of ACTH-independant Cushing’s syndrome?
Adrenal tumour (adenoma or carcinoma)
Corticosteroid therapy (e.g. for asthma, IBD)
What are some physiological causes of hyperprolactinaemia?
Pregnancy, lactation, stress
What are some pharmacological causes of hyperprolactinaemia?
DA depleting drugs and DA antagonist drugs
What are some pathological causes of hyperprolactinaemia?
Pituitary hypothyroidism Pituitary lesions (prolactinoma or pituitary 'stalk pressure')
Give some classes of drugs which may cause hyperprolactinaemia
Dopamine antagonists
DA_depleting agents
Oestrogens
Some antidepressants
What are some clinical features in adults of hypopituitarism?
Tiredness, weight gain, depression, reduced libido, impotence, menstrual problems
Skin pallor
Reduced body hair
What are some clinical features in children of hypopituitarism?
Reduced linear growth
Delayed puberty
What is Diabetes Insipidus?
Usually results from a lack of ADH and is characterised by extreme thirst and excretion of high levels of very dilute urine
What test should be done to exclude DI?
Water deprivation test
What is the drug treatment for a hypersecreting prolactinoma (pituitary tumour)
Dopamine agonists
What are the two drug therapies for hypersecreting pituitary tumours causing acromegaly?
Somatostatin analogues
GH receptor analogues
What are the drug therapies for treating hyposecretion caused by a pituitary tumour?
Cortisol, T4, sex steroids, GH, desmopressin
What is a microprolactinoma?
A tiny pituitary tumour which causes hyposecretio of prolactin
What is the drug treatment for microprolactinoma?
Dopamine agonists
