Diseases of the Endocrine System Flashcards
Location of the pituitary gland
Behind the optic chiasm in the Sella Turcica
Anterior lobe
Adenohypophysis - 75% of pituitary and generally more important
Causes of anterior pituitary hypofunction
Vascular e.g. infarction Inflammation - granulomatous Trauma Autoimmune - pituitary autoimmune disease Metabolic Infection Neoplasia - non-secretory adenoma, metastatic Doctors - drugs affecting hormone status VITAMIN D is the mnemonic
Primary pituitary tumours
Mainly adenomas
May be secretory
Can cause local effects due to pressures on surrounding structures e.g. visual field defect
Prolactinoma
Prolactin secreting hormone
Can cause menstrual dysfunction and galactorrhea in women
Can cause gynecomastia, loss of libido and erectile dysfunction in men
ACTH tumour
Increases cortisol to excess
Causes Cushing’s syndrome
Growth hormone secreting tumour
Causes gigantism inc. acromegaly
Hashimoto’s disease
Also called chronic lymphocytic thyroiditis
Autoimmune chronic inflammatory disorder
More common in women
Peak age 59 years
Many patients develop hypothyroidism
Diffusely enlarged non-tender gland
80-fold increase of thyroid lymphoma if untreated
Increased risk of papillary thyroid cancer
Test for Hashimoto’s
Serum thyroid antibodies (no one specific antibody)
Graves’ disease
Diffuse hyperplasia Autoimmune disease Generally in younger people Females over males Pretibial myxoedema - rash on anterior surface of the legs Thyroid eye disease
Tests and examination for Graves’
Thyroid diffusely enlarged
T3 and T4 elevated, TSH markedly decreased due to negative feedback from T4
Multinodular goitre
Enlargement of thyroid +/- nodularity Most are euthyroid Large 'dominant' nodules can be mistaken for thyroid carcinoma Compressive symptoms Can be caused by iodine deficiency May appear calcified on an X-ray
Follicular adenoma
Benign encapsulated tumour
Can cause similar symptoms to Hashimoto’s
Most common kind of thyroid cancer
Differentiated thyroid carcinoma - papillary or follicular types
Papillary carcinoma
Accounts for over 70% of thyroid carcinoma
Female predominance 2.5:1
Wide age range with a mean of 43 years
Familial, autosomal dominant
Related to radiation exposure
Frond-like structures macroscopically
Microscopically nuclei can look transparent