Endocrinology Flashcards
Acromegaly
features and investigation
acess growth hormone
clinical Features Large hands and feet Outward growth of the jaw and head with increased interdental spacing and macroglossia Headaches Erectile dysfunction Voice change Increased sweating Mood disturbances Fatigue.
- measure IGF-1.
- growth hormone is measured following intake of oral glucose (Oral Glucose Tolerance Test) to see if growth hormone is inappropriately suppressed
Acromegaly management
First line treatment for acromegaly is trans-sphenoidal surgery.
Other options for refractory cases or for patients who cannot undergo surgery:
Somatostatin receptor ligands (SLR) such as Octreotide
Pegvisomant (GH analogue)
Cabergoline (Dopamine agonist)
Radiotherapy
Primary Causes of Adrenal Insufficiency (addisons .)
Primary Causes of Adrenal Insufficiency (Addison’s)
Auto-immune (most-common)
Surgical removal
Trauma
Infections (Tuberculosis: more common in the developing world)
Haemorrhage (Waterhouse-Friderichsen syndrome)
Infarction
Less common: neoplasm, sarcoidosis, amyloidosis
Addisons clinical features
Clinical Features
Hypotension
Fatigue and weakness
GI symptoms
Syncope
Pigmentation (due to an increase in ACTH pre-cursors).
Approximately 60% of patients with auto-immune Addison’s disease have vitiligo or other autoimmune endocrinopathies.
Amiodarone induced thyrotoxicosis
managment
Management
Treatment depends on the underlying type and may involve anti-inflammatories such as steroids plus anti-thyroid drugs (Carbimazole).
Close discussion with the Cardiology team is important to decide whether the Amiodarone needs to be stopped or substituted.
Abnormalities if thyroid function can occur in up to 50% of patients taking Amiodarone.
Cushing’s syndrome
investigation
To identify cortisol excess:
24 hour urinary free cortisol
Low-dose Dexamethasone suppression test
Localisation:
Plasma ACTH High-dose dexamethasone suppression test Inferior petrosal sinus sampling MRI of the pituitary CT Chest and Abdomen (suspected tumour)
Medical Management of cushings
Blockers of the steroid synthesis pathway should be used first line, with Metyrapone the most commonly used.
Other treatments include Ketoconazole which is an adrenolytic agent, Mifepristone which is a glucocorticoid antagonist and Pasireotide which binds to somastostatin receptors.
Causes of cranial DI
idiopathic post head injury pituitary surgery craniopharyngiomas histiocytosis X DIDMOAD is the association of cranial Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy and Deafness (also known as Wolfram's syndrome) haemochromatosis
Causes of nephrogenic DI
genetic: the more common form affects the vasopression (ADH) receptor, the less common form results from a mutation in the gene that encodes the aquaporin 2 channel
electrolytes: hypercalcaemia, hypokalaemia
lithium
lithium desensitizes the kidney’s ability to respond to ADH in the collecting ducts
demeclocycline
tubulo-interstitial disease: obstruction, sickle-cell, pyelonephritis
Cranial DI deprevation tests
Starting plasma osm. high
Final urine osm. supressed
Urine osm. post-DDAVP (dex) high
nephrogenic DI deprevation tests
Starting plasma osm. high
Final urine osm. supressed
Urine osm. post-DDAVP (dex) supressed
Management of ertile dysfuntion
Depends on cause Psychosexual therapy Oral phosphodiesterase inhibitors (Sildenafil) Vacuum aids Intra-cavernosal injections Prosthesis
Causes of Smooth Goitre
Graves' disease Hashimoto's disease Drugs (e.g. lithium, amiodarone) Iodine deficiency/excess De Quervain's thyroiditis (painful) Infiltration (e.g. sarcoid, haemochromatosis)
Causes of Nodular Goitre
Toxic solitary adenoma Non-functional thyroid adenoma Multinodular goitre Thyroid cyst Cancer
primary hyperparathyroidism i
‘bones, stones, abdominal groans and psychic moans’
polydipsia, polyuria
peptic ulceration/constipation/pancreatitis
bone pain/fracture
renal stones
depression
hypertension
raised calcium, low phosphate Phosphate (Low)