Diseases of the endocrine system Flashcards
What do the following systems affect:
- Endocrine
- Autocrine
- Paracrine
- E= hormones directly into blood act systemically
- P= hormones act locally
- A= affects cell secreting the protein
What are causes of anterior pituitary hypofunction?
-Tumours=non secretory adenoma, metastatic carcinoma
-Trauma
-Inflammation= autoimmune, infections, granulomatous
-Infarction
Iatrogenic
Describe primary pituitary tumours
- Majority adenomas & benign
- Derived from any hormone producing cell
- Local effects due to pressure on optic chiasma/ adjacent pituitary
What types of anterior pituitary adenomas are there?
- Prolactinoma- menstrual disturbance, galactorrhoea
- Growth hormone secreting= gigantism in children, acromegaly in adults
- ACTH secreting-Cushing’s syndrome
Describe acute thyroiditis?
- Acute inflammation of thyroid parenchyma
- Local or sytemic infection
- Generalised sepsis
- Fever, chills, pain, malaise, swelling of anterior neck
What is palpation thyroiditis?
- Microscopic Granulomatous foci centered on thyroid follicles
- Due to rupture of thyroid follicles
- Presents as thyroid nodule
What is Riedel thyroiditis?
- Rare fibrosing form of chronic thyroiditis
- Firm goitre
- Stridor, hoarseness, dysphagia
- Benign
Describe Hashimoto’s disease
-Autoimmune chronic inflammatory disorder
-Associated with diffuse enlargement of thyroid autoantibodies
-Chronic lymphocytic thyroiditis w/germinal centre formation
-Females most common
-Elevated serum thyroid antibodies
-Many become hypothyroid
-Inc risk of thyroid lymphoma & papillary carcinoma
-
Describe Grave’s disease
- Diffuse hyperplasia
- May develop permanent hypothyroidism
- Autoimmune process & diffuse hyperplasia of follicular epithelium
- Females more common
- Pretibial myxoedema, hair loss, wide-eyes stare, tachycardia, hyperreflexia, proptosis
Describe a multinodular goitre
- Enlargement of thyroid
- Most patients euthyroid
- Tracheal compression or dysphagia may develop
Describe follicular adenoma
- Benign encapsulated tumour
- Follicular cell differentiation
- Females most common
- Painless neck mass
- Solitary nodule on one lobe
- Cold nodule on radioactive iodine imaging
What is the most common type of thyroid cancer? Describe it
- Papillary carcinoma
- Familial, autosomalD non-medullary thyroid carcinoma
- Activation of RET or NTRK1
- Chromosomal translocations or inversions, RAS/BRAF mutations,
- Causes: Cowden’s syndrome, radiation exposure, therapeutic irradiation
- Granular, cystic, some encapsulated, infiltrative
Describe follicular neoplasms
- Follicular adenoma
- Minimmaly invasive follicular carcinoma
- Hurthle cell neoplasms/ oncocytic carcinoma (acidophilic cells in canine thyroid), incidence of cervical lymph node mets
- Widely invasive follicular carcinoma
Name the types of thyroid carcinoma
- Papillary carcinoma
- Insular carcinoma
- Anaplastic carcinoma (rapidly enlarging thyroid mass, inoperable)
- Medullary carcinoma (differentiation to parafollicular C cells, mutation in RET gene, autosomalD, MEN 2a&2b)
Describe primary thyroid lymphoma
- Associated with lymphocytic thyroiditis
- Diffuse large B-cell
- Rapidly enlarging mass, pain, dysphagia, cervical lymphadenopathy
What tumours are likely to metastasise to the thyroid?
- Renal cell carcinoma
- Melanoma
- Breast cancer
- Small cell lung cancer
- Neuroendocrince carcinoma
What are the types of hyperparathyroidism?
- Primary= Excessive section of parathyroid hormone from one of more glands
- Secondary= Hyperplasia of glands with elevated PTH in response to hypocalcaemia
- Tertiary= Adenoma associated with longstanding secondary hyperparathyroidism
What are causes of secondary hyperparathyroidism?
- Renal insufficiency
- Vit D deficiency
- Malabsorption
What is the pathogenesis of primary hyperparathyroidism?
- Aging
- MEN 2a
- Association with ionizing irradiation
- Tumorigenesis
- Arterial hypertension, hypercalcaemia, dec renal function, psych problems, osteoporosis, urolithiasis
- Mostly single adenoma
What is primary chief cell hyperplasia?
- Non neoplastic increase in parathyroid parenchymal tissue
- Abnormal calcium metabolism
- Fatigue, lethargy, anorexia, weakness, vomiting
- Bones, stones, abdo moans
- Elevated Ca, decrease in organic phosphorous, inc parahormone levels
Describe parathyroid adenoma
- Encapsulated benign neoplasms of parathyroid cells
- symptoms of hypercalcaemia
- MEN1&2 syndrome, jaw tumour syndrome
- Single enlarged parathyroid gland remaining glands suppressed & small
Describe secondary & tertiary parathyroidism
- non-neoplastic inc in parathyroid parenchymal cell mass within all parathyroid
- Common with renal failure & dialysis
- Identical path to primary hyperplasia associated with massive gland enlargement
Describe parathyroid carcinoma
-Malignant tumour derived from parathyroid parenchymal cells
Describe adrenal congenital hypoplasia
- Reduced vol of adrenocorticol tissue leading to adrenal cortical insufficiency
- High mortality
- Males, X-linked
- Hypoadrenalism
- Managed with mineralocorticoids & glucocorticoids
Describe congenital adrenal hyperplasia
- Inherited
- Deficiency of enzymes required for synthesis of glucocorticoids & mineralocorticoids
- 21 hydroxylase deficiency most common
- Deficiencies of corticol & aldosterone secretion
- Genital ambiguity in F, normal M
- Advanced bone growth & premature epiphyseal maturation
Describe Addison’s disease
- Primary adrenal cortical insufficiency
- Adrenal destruction
- Autoimmune form or TB
- Triad= hyperpigmentation, postural hypotension, hyponatraemia
- Long term steroid replacement
Describe adrenal cortical carcinoma
- Malignant
- Abdominal mass
Describe adrenal cortical nodule
-Benign non-functional nodules of adrenal cortex
Describe an adrenal cortical adenoma
- Benign neoplastic proliferation of adrenal cortical tissue
- Endocrince hyperfunctioo
- Aldosterone producing tumours cause Conn’s syndrome
- Unilateral mass yellow/brown nodules
- Formed from lipid filled adrenal cortical cells
What is Conn’s syndrome
- excess production of aldosterone by the adrenal glands resulting in low renin levels
- high blood pressure=poor vision or headaches
Describe phaeochromocytoma
- Catecholamine secreting tumour from adrenal medulla
- Sporadic or familial MEN 2a/2b, von reckling, von hippel
- Elevated urine catecholamines, (nor)adrenaline
- Anxiety, headaches, palpitations, hypertensions
