¡GoConqr estrena diseño! Cuéntanos qué te parece.

Regístrate gratis

Fichas

Calcium disorders

Anna Hogarth Met3B Inglés 43 fichas

Fichas del conjunto (43)

  1. 1Define hypercalcemiaCalcium levels above 2.6 mmol/L
    (normal range is 2.1 - 2.6)
  2. 2What is primary hyperparathyroidism?Excessive PTH production from the parathyroid gland
  3. 3What is secondary hyperparathyroidism?Raised PTH due to a secondary cause
  4. 4What is tertiary hyperparthyroidism?Raised PTH due to loss of parathyroid sensitivity to calcium levels etc. typically occurs in chronic renal disease
  5. 5How does PTH act to increase serum calcium?1) Increases osteoclast activity
    2) Increase resorption from the kidneys (and reduces PO4-)
    3) Increase renal Vit D (1,25 dihydroxyvitamin D3) production through increasing a1-hydroxylase. This increases absorption across the gut
  6. 6How does hyperparathyroidism present?1) High serum calcium - weak, tired, depressed, polyuria, thirsty, dehydrated, renal stones, abdominal pain, pancreatitis, ulcers
    2) Bone resorption - osteoporosis, fractures, bone pain
    3) Hypertension
  7. 7What causes primary hyperparthyroidism?1) 80% is due to solitary adenoma
    2) 20% is due to hyperplasia of all glands
    3) 0.5% is parathyroid cancer
  8. 8What would you expect serum PTH and Ca2+ to be in primary hyperparathyroidism? What else can cause this?1) Raised Ca2+ and PTH
    2) Tertiary hyperparathyroidism, thiazides, lithium, and familial hypocalciuric hypercalcaemia
  9. 9What would you expect PO4-, ALP and 24 hr urinary calcium to reveal in primary hyperparathyroidism?1) Low PO4- (unless renal failure)
    2) High ALP
    3) Raised 24hr urinary calcium
  10. 10What imaging tests might you do in hypercalcaemia?1) X-ray hands to show osteitis fibrosa cystica (due to severe resorption, rare) which may show up as cysts, subperiosteal erosions or brown tumours of phalanges
    2) DEXA for osteoporosis
  11. 11How is mild hypercalcaemia managed?Increase fluid intake to avoid stones, avoid thiazides and high calcium & vit D intake. Review 6-monthly
  12. 12What are the indications for excision of adenoma or all four hypoplastic glands in primary hyperparathyroidism?Will prevent fractures and peptic ulcers
    1) High serum or urinary calcium
    2) Bone disease
    3) Osteoporosis
    4) Renal calculi
    5) Reduced renal function
    6) Patient older than 50
  13. 13What are the complications of parathyroid surgery?1) Recurrent laryngeal damage - hoarse voice
    2) Hungry bone syndrome (symptomatic low Ca2+) - check Ca2+ daily for 14 days post op
    3) 8% recurrence over 10 years
  14. 14What are MIBI, US and intra-operative PTH sampling used for?1) MIBI and US can localise an adenoma
    2) Intraoperative PTH sampling can confirm removal
  15. 15What is cinacalcet? Side effects?1) Calcimimetic which can be used to increase parathyroid sensitivity to calcium, thus reducing PTH secretion
    2) Myalgia and low testosterone
  16. 16What Ca2+ and PTH values would you expect to see in secondary hyperparathyroidism?Low calcium, high PTH
  17. 17What causes secondary hyperparathyroidism?Low vitamin D intake or chronic renal failure (no a1-hydroxlase)
  18. 18How is secondary hyperparathyroidism managed?1) Phosphate binders
    2) Vit D
    3) Cinacalcet if PTH > 85pmol/L
    4) Parathyroidectomy is tricky
  19. 19What Ca2+ and PTH values would you expect to see in tertiary hyperparathyroidism?High calcium and very high PTH - after prolonged secondary hyperparathyroidism, the gland acts autonomously due to prolonged hyperplastic or adenomatous change. No feedback control
  20. 20What causes malignant hyperparathyroidism? What Ca2+ and PTH values would you expect to see?Parathyroid-related protein (PTHrP) is produced by some squamous cell lung cancers, breast and renal cell carcinomas. Mimics PTH which leads to raised calcium. As such PTH is low (PTHrP is not detected on the assay)
  21. 21What are Multiple Endocrine Neoplasia (MEN) syndromes?Functioning hormone producing tumours in multiple organs - autosomal dominant inheritance
    MEN-1
    MEN-2
    Von Hippel-Lindau
    Peutz-Jeghers
  22. 22What characterises MEN-1?3 Ps
    1) Parathyroid hyperplasia/adenoma (95%), hypercalcaemia
    2) Pancreatic tumours (75%) (i.e insulinomas, gastromas, glucagonomas)
    3) Pituitary prolactinoma (50%) or GH (acromegaly)
  23. 23What characterises MEN-2a?Thyroid medullary carcinoma in 100%
    2 Ps
    1) Pheochromocytoma (50%)
    2) Parathyroid hyperplasia (80%, but less than 20% have high calcium)
    RET proto-oncogene
  24. 24What characterises MEN-2b?Thyroid Medullary Carcinoma
    1P
    1) Pheochromocytoma
    RET proto-oncogene
  25. 25Symptoms of hypocalcemia?1) Numbness and/or tingling of hands, feet, or lips
    2) Muscle cramps
    3) Muscle spasms
    4) Seizures
    5) Muscle weakness
  26. 26What causes primary hypoparathyroidism? What blood results would you expect? Signs? Treatment?1) Gland failure - autoimmune, congenital
    2) Low calcium, high PO4- (or normal), normal ALP
    3) Those of hypocalcemia
    4) Calcium supplements + calcitriol (or synthetic PTH)
  27. 27What causes secondary hyperparathyroidism?Radiation, surgery, hypomagnesemia (magnesium is needed for PTH secretion)
  28. 28What is pseudohypoparathyroidism? Pseudopseudohypoparathyroidism?1) Failure of target cell response to PTH - short metacarpals, round face, short stature, calcified basal ganglia, low IQ. Low calcium, high PTH, normal or high ALP. Treatment as for primary hypoparathyroidism
    2) Morphological features of pseudohypoparathyroidism but normal biochemistry
  29. 29How does acute hypercalcaemia present?Bones, stone, groan and psychic moans:
    Abdominal pain, vomiting, constipation, polyuria, polydipsia, depression, anorexia, weight loss, tiredness, weakness, hypertension, confusion, pyrexia, renal stones, renal failure, ectopic calcification
  30. 30What are the most common causes of hypercalcaemia?Malignancy - either metastases, myeloma or PTHrP
    Primary/tertiary hyperparathyroidism
    Can be vit D intoxication, familial benign hypocalciuric hypercalcaemia etc.
  31. 31If albumin is raised, what does it suggest about the cause of the hypercalcaemia?Likely dehydration (check if urea is raised, if not; cuffed specimen).
  32. 32If albumin is low, what does it suggest about the cause of the hypercalcaemia? (Think about ALP as differentiator)Could be cancer - bone metastases will cause raised ALP. (Sarcoidosis, thyrotoxicosis and lithium will have similar profile)
    If normal ALP then could be myeloma, vitamin D excess, sarcoidosis. If HCO3- also raised then think milk-alkali syndrome
  33. 33If albumin is normal and phosphate is low or normal - what is the likely cause?Primary or tertiary hyperparathyroidism
  34. 34How (and when) is hypercalcaemia managed?If calcium is higher than 3.5mmol/L and symptomatic
    1) Correct dehydration (0.9% saline)
    2) Bisphosphonates - inhibit osteoclast activity, therefore reducing bone turnover. Give single dose, will lower calcium over 2-3 days, max result seen at around a week
    3) Manage further by treating underlying cause
  35. 35What is pamidronate? Zoledronic acid? Treatment regime? Side effects?1) Bisphosphonates
    2) Infuse slowly in hypercalcaemia i.e. 30mg in 300mL 0.9% saline
    Ca < 3 give 15-30mg
    3-3.5 give 30-60mg
    3.5-4 give 60-90mg
    4+ give 90mg
    3) flu symptoms, low PO4, bone pain, myalgia, nausea, vomiting, headache, lymphocytopenia, low MG, low Ca2+, seizures
  36. 36How does magnesium relate to calcium metabolism?Needed for secretion of PTH - low magnesium can cause hypoparathyroidism
  37. 37What are the features of hypocalcaemia?S-spasms (carpopedal spasm on brachial artery compression - Trousseau's sign)
    P- perioral paresthesia
    A - Anxious, irritable, irrational
    S - seizure
    M - muscle tone increase (colic, dysphagia, wheeze)
    O - orientation impaired (confusion)
    D - dermatitis (atrophic/exfoliative)
    I - impetigo herpetiformis (low calcium and pustules in pregnancy)
    C - Chvostek's sign, choreo athetosis, cataract, cardiomyopathy
  38. 38What is Chvostek's sign?Tap the parotid, will cause a twitch due to facial artery impulse
  39. 39What are the causes of hypocalcemia with raised PO4-?1) Chronic kidney disease
    2) Hypoparathyroidism
    3) Pseudohypoparathyroidism
    4) Acute rhabdomyolysis (release of PO4- and acidity causes precipitation of calcium)
    5) Hypomagnesaemia
  40. 40What are the causes of hypocalcemia with normal or low PO4-?1) Vit D deficiency
    2) Osteomalacia (raised ALP)
    3) Acute pancreatitis
    4) Overhydration
    5) Respiratory alkalosis (total Ca2+ is normal but ionized calcium falls due to raised pH)
  41. 41How is mild hypocalcaemia managed? Hypocalcemia in chronic kidney disease? If there are severe symptoms?1) Give calcium 5mmol/6h PO and monitor serum Ca2+
    2) Alfacalcidol (vit D) e.g. 0.5-1mcg/24h PO
    3) Give 10mL of 10% calcium gluconate (2.25mmol) IV over 30 mins to replace calcium and stabilise membranes.
  42. 42How does PTH differ to calcitriol (activated vit D3) in its regulation of calcium?PTH causes renal resorption of calcium but PO4- excretion. Vit D3 increase resorption of both.
  43. 43How do albumin concentrations affect serum calcium?Around 40% of calcium is bound to albumin, have to correct total calcium by increasing free calcium by 0.1mmol/L for every 4g/L that albumin is under 40g/L

Información

Descripción
(Endocrinology) Met3B Fichas sobre Calcium disorders, creado por Anna Hogarth el 07/03/2020.
Creado por
Anna Hogarth
Visitas
0
Valoración

Más sobre Parathyroid and Calcium Disorders

Escríbenos

¿Sobre qué es tu mensaje?

¿Qué te parece el nuevo diseño?

¿Te gusta?