Endocrine Flashcards
Treatment for hypothyroidism?
Levothyroxine (T4) – review at 12 weeks, adjust 6 weekly
NB: give smaller doses if elderly as risk of angina or MII
What is Hashimoto’s thyroiditis? What can it causE?
anti-TSH, anti-TPO, anti-TG. can cause hypothyroidism
what is Grave’s disease?
IgG autoantibodies bind to and stimulate TSH receptors (triggers = infection, stress, childbirth)
Eye disease, pretibial myxoedema, thyroid acropachy
Autoimmune (vitiligo, type 1 DM, Addison’s)
Causes Hyperthyroidism
What else causes hyperthyroidism/
TOXIC MULTINODULAR GOITRE
- TOXIC ADENOMA
- ECTOPIC THYROID TISSUE (mets / struma ovarii)
- EXOGENOUS (Iodine / T4 excess)
- DE QUERVAIN’S THYROIDITIS (post-viral)
What causes hypothyroidism?
PRIMARY HYPOTHYROIDISM (↓T4)
Primary atrophic hypothyroidism
Hashimoto’s thyroiditis (anti-TSHR, anti-Tg, anti-TPO)
Iodine deficiency
Post-thyroidectomy / radioiodine / antithyroid drugs
Lithium / amiodarone
SECONDARY HYPOTHYROIDISM (↓TSH) Hypopituitarism
Signs and symptoms of hypothyroidism?
Bradycardic Reflexes relax slowly Ataxia (cerebellar) Dry, thin hair / skin Yawning / drowsy / coma Cold hands +/- ↓T°C Ascites Round puffy face Defeated demeanour Immobile +/- Ileus CCF CVS: - RS: Hoarse voice GI: Constipation Int: Cold intolerance Endo: Weight gain UG: Menorrhagia MSK: Myalgia, weakness Neuro / Psych: Tired, low mood, dementia
What investigations do you do for hypothyroidism?
INVESTIGATIONS:
TFT (thyroid function tests)
Lipids/cholesterol (should be increased)
(c) FBC (macrocytosis)
what are the SX for hyperthyroidism?
CVS: Palpitations RS: - GI: Diarrhoea Int: Heat intolerance Endo: ↓Weight, ↑appetite UG: Oligomenorrhoea +/- infertility MSK: - Neuro / Psych: Tremor, irritability, labile emotions
and
HANDS:
- Palmar erythema; warm, moist skin; fine tremor
PULSE:
- Tachycardia; SVT; AF
FACE:
Thin hair; lid lag / retraction
NECK:
Goitre; nodules; bruit
What Ix do yu do for hyperthyroidism?
INVESTIGATIONS:
(a) TFT
(b) FBC (normocytic anaemia)
(c) ESR (↑)
(d) Calcium (↑)
(e) LFT (↑)
(f) Thyroid autoantibodies
(g) Visual fields, acuity, eye movements
How do you treat hyperthyroidism?
(i) β-blockers:
- Propanolol (rapid control of symptoms)
(ii) Antithyroid medication:
Titration (carbimazole: SE = AGRANULOCYTOSIS)
Block and replace (carbimazole + thyroxine)
these inhibit the action of TPOy
(iii) Radioiodine (131I)
(iv) Thyroidectomy
What is thyroid eye diseasE?
bulging of eyes (pushed forward) due the eye muscles and fatty tissue binding to the eye and causing inflammation. can lead to double vision, proptosis, exophthlamos, opthalmoplegia. grittiness in the eyes, eye discomfort and diplopia.
How can TED be treated?
eyelid surrgeyr, corticosteroids - methylprednisolone, stop smoking, sunglasses, surgical decompression.
What happens when a cell gets insufficient insulin?
the insulin receptor in the cell is not activiated, the glucose channel isnt opened so the glucose in the blood builds. lack of insulin stimulates glycogen. Cell releases Cortisol, adrenaline and GH to produce energy.
What does GH do?
reduces insulin activity and glucose utilisation so increases blood glucose
What does adrenaline do in DM?
increases hydrolyiss of fatty acids and increases ketones. this can lead to diabetic ketoacidosis.
What does cortisol do?
increases proteolysis which produces more glucose
How does DKA cause hyperkalaemia?
High acidity causes inreas in H+. these are transported into cells and exchanges for K+. The transporter which pumped K+ into the cell and Na+ outside is controlled by insulin. Because of the lack of insulin this channel no longer functions. this leads to excess K+ in the blood
First line Tx for DM2?
Metformin
What does Metformin do?
Increases insulin sensitivity in GLUT4 receptors in liver,
increases gluces uptake
decreases gylocogenolysis