5. Thyroid and Misc Endo Flashcards
Pathway to releasing thyroid hormones
Pituitary produces TSH
Follicular cells produce T4 and T3. T4 turns to T3 too.
Hyperthyroid symptoms?
Tremor Anxiety Palpitations Heat into Diarrhoea Oligomenorrhoea
Hypothyroidism symptoms?
lethargy Cold into Weight gain Constipation Mehorrhagia
Causes of hyperthyroidism
Hyper -
Graves
Toxic multinoduler goitre
Thyroiditis
How do we treat hyperthyroidism?
Propanolol
Carbimazole (can cause agranulocytosis)
Radioiodine
Bilateral exophthalmos?
Occurs in grave’s disease in 25-50% of patients.
Causes diplopia and related to lid lag.
Signs of thyroid cancer?
Hoarse voice Dysphagia Haemoptysis Airway obstruction Cervical lymphadenopathy
Most common thyroid cancers?
Papillary carcinoma (70%) Follicular carcinoma (20%) (Hurthle cell is rare variant)
What is MEN 1 syndrome symptoms?
Parathyroid adenoma, increasing calcium
Pancreatic adenoma, causing peptic ulcers
Pituitary adenoma, causing low libido and mass effect
Lots of others e.g. carcinoid, adrenal
Needs a CT/MRI of whole body
Hypercalcaemia pneumonic?
Stones, groans (GI), bones and psychic moan.
What are MEN 2a and 2b?
Both have medullary thryoid cancer plus
A - parathyroid adenomas, phaeochromocytomas
B (associated with marfan’s) - Phaeochromocytomas (associated with marfan’s)
need genetic testing for RET ti differentiate, calcitonin high, urine catecholamines (cant spell)
What is carcinoid syndrome?
Neuroendocrine cells (e.g. in stomach) rapid division causing tumour that metastasises to liver . You get a build up of serotonin, bradykinin and histamine causing features!
Features of carcinoid syndrome?
Flushing Diarrhoea SOB Pulmonary stenosis Abdo pain Itching
What normally regulates serotonin production by neuroendocrine cells?
Somatostatin
Investigations for carcinoid syndrome?
Urinary 5HI-AA
CT Scan
Octreotide scan
HPG Axis?
GnRH from hypothalamus
Ant pit produces LH and FSH
Lh - leydig cells
fSh - sertoli cells for spermatogenesis
LH - theca cells for prog
fSh - granuloSa cells for oestrogen
Hypogonadism in female causes?
Primary - Genetics e.g. turner’s syndrome (45X0), gonadal damage, primary ovarian failure and PCOS
Secondary (pituitary or hypothalamus) - Kallmann’s, tumours, hyperprolactinaemia, functional (low bmi, excess exercise, stress), contraceptive pill use
Other - pregnancy
Hypogonadism in males causes?
Primary - Genetics e.g. klinefelter’s (47XXY) or crytochidism, gonadal damage, post-orchitis (mumps)
Secondary - same as females
Features of hypogonadism?
Delayed puberty Infertility Low libido Amenorrhoea Night sweats/hot flushes in women Erectile dysfunction Symptoms of cause
Investigations in hypogonadism?
Pregnancy test LH/FSH (high in primary, low in secondary) Prolactin Testosterone/oestragiol TFTs Karyotyping MRI
HPS axis (growth hormone)
Growth hormones releasing hormone from hypo goes to ant pit
Growth hormone from ant pit to act on liver, muscle, bone and kidneys to produce IGF-1 a s well as increasing blood glucose, insulin resistance, increase muscle growth and bone thickness.
Somatostatin and IGF-1 negatively regulate the axis
What causes acromegaly?
Mostly pituitary adenoma of somatotrophs that produce lots of GH increasing IGF-1
Features of acromegaly?
Coarse features Prognathism and large tongue Spade-like hands and large feat Excessive sweating Organomegaly Headaches Visual disturbance Hyperprolactinaemia Hypopituitarism
Complication of acromegaly?
Carpal tunnel Hypertension Diabetes mellitus Cardiomyopathy Colorectal cancer
