Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

endocrine > Calcium Disorders > Flashcards

Calcium Disorders Flashcards

1
Q

What are the common causes of hypercalcaemia?

A

90% are either:

  • Primary Hyperparathyroidism
  • Malignant Hypercalcaemia

OTher:

Miscellaneous:

  • Thyroidectomy
  • Acromegaly
  • Adrenal insufficiency
  • Parental nutrition

Parathyroid:

  • Familial Hypocalciuric Hypercalcaemia (FHH)
  • MEN
  • Familial hypocalciuric hypercalcemia
  • Tertiary hyperparathyroidism

Non-parathyroid:

  • Vitamid D intoxication
  • Chronic granulomatous infiltration e.g. Sarcoid, TB, histoplasmosis

Meds:

  • Drugs e.g. Thiazide diuretic or Lithium
  • XS Vitamin A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What causes Primary Hyperparathyroidism?

A

85% are adenomas
~15% are 4 gland hyperplasia

Very rarely:

  • MEN 1 or 2A
  • Parathyroid Carcinoma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How does Hypercalcaemia present?

A

GI - Anorexia, Constipation & N&V

CV - Short QT, Hypertension & Bradycardia

Neuro - Loss of Conc. & confusion

Renal - Polyuria & Polydipsia + Nephrolithiasis

MSK - Muscle Weakness & bone pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does Primary Hyperparathyroidism present?

A

Its generally asymptomatic but can cause symptoms of hypercalcaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Familial Hypocalciuric Hypercalcaemia?

A

An autosomal dominant disorder causing Calcium-Sensing Receptor (CaSR) defects

  • Low levels of urinary calcium
  • PTH is elevated or normal
  • No indication of abnormal parathyroid tissue on US.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What tests are appropriate for Hypercalcaemia?

hint theres loads

A
  • Serum Ca, PO4/mg, PTH & Albumin
  • Serum ACE (Sarcoid)
  • 24 hour urine collection for calcium (low = FHH)
  • U&Es
  • ALKP
  • Lymph node exam (malignancy)
  • Myeloma screen (osteolytic metastases)
  • ECG (short QT)
  • FH
  • Med History

Abdo US for kidney stones
Parathyroid US for adedomas etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the initial tests for hypercalcaemia?

A

Serum Ca / PO4 / PTH / Albumin

FH & Med history

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the “levels” of hypercalcaemia?

A

<3mmol/l - Generally aymptomatic

3-3.5mmol/l -~symptomatic & prompt treatment needed

> 3.5mmol/l - Emergency. Risks Dysrhythmia & coma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How do you treat hypercalcaemia first?

A

Rehydration & IV bisphosphonates (inhibit osteoclasts)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What can you give hypercalcaemics when bisphosphonates fail/arn’t tolerated?

A

Calcitonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What treatments are there for to decrease GI absorption disease causing hypercalcaemia?

A

Glucocorticoids e.g. Hydrocortisone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How would we treat Primary Hyperparathyroidism Hypercalcaemia?

A

Parathyroidectomy

OR

Calcimetics e.g. Cinacalcet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Summary of Hypercalcaemia treatments?

A

1st) Rehydrate and IV bisphosphonates

  • Calcitonin
  • Cinacalcet
  • Parathyroidectomy
  • Glucocorticoids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does PTH differentiate the cause of Hypercalcaemia?

A

In hypercalcaemia PTH should be low.
If it is then the cause is outside the Parathyroid e.g. malignancy or drugs

If its high then theres some reason PTH is overproduced e.g. FHH, renal failure or Primary hyperparathyroidism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the main causes of Hypocalcaemia?

A

Low PTH aka hypoparathyroidism:

  • Neck surgery e.g. thyroidectomy
  • Autoimmune
  • Infiltration of parathyroid e.g. hemochromatosis
  • Radiation
  • HIV

High PTH (2nd* Hyperparathyroidism due to hypocalcaemia):

  • Renal Disease
  • Pseudohypoparathyroidism
  • Pancreatitis: FFA binding to calcium causing it to be excreted
  • Vit D deficiency

Drugs

  • Inhibition of Bone resorption e.g. Bisphosphonates
  • Calcium chelators (increase excretion)
  • Phenytoin (inactivates Vitamin D)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Pseudohypoparathyroidism?

A

A set of disorders in which target organs like kidneys & bone become unresponsive to PTH

17
Q

What special about pseudohypoparathyroidism presentation?

A

Albright’s Hereditary Osteodystrophy (AHO):

  • Obesity
  • Short Stature
  • Short Metacarpals

Low Ca
High PO4 & PTH (hence pseudo)

18
Q

At what Serum Ca2+ level do symptoms of hypocalcaemia appear?

A

Around 1.9mmol/l

19
Q

How does hypocalcaemia present?

A

Lots of symptoms, main ones are:

  • Paraesthesia
  • Muscle twitchin
  • Trosseaus sign
  • Chovstek’s Sign

Prolonged QT
Hypotension
Papilloedema

20
Q

What are the named signs of hypocalcaemia?

A

Trosseau’s sign = Attach a tight BP cuff and watch the patients hand slowly form a claw

Chovstek’s Sign = Facial twitch when you tap on the parotid over the Facial nerve

21
Q

What tests are appropriate for Hypocalcaemia?

A

Serum Ca, albumin, PO4

PTH (High Pseudoparathyroidism vs low Hypoparathyroidism)

Mg (Mg deficiency)

U&Es (renal failure)

Vit D (Vit D deficiency)

ECG

22
Q

Explain how blood tests will appear for the 2 biggest causes of hypocalcaemia?

A

Vit D deficiency - Low Ca, low PO4/Mg (U&E’s) ; high PTH

Hypoparathyroidism - Low Ca, High PO4/mg (U&Es); low PTH

Also pseudoparathyroidism
- Low Ca, High PO4 and high PTH

23
Q

How do you treat mild Hypocalcaemia?

A

Mild meaning >1.9mmol/l and asymptomatic.

Put them on oral Ca2+ suppleents

Also Oral Vit D tablets and Mg replacement as appropriate

24
Q

How do you treat severe hypocalcaemia?

A

Severe meaning symptoms or <1.9mmol/l
Considered a medical emergency

IV Calcium Gluconate

Then treat cause

25
Q

why do you test albumin?

A

Some calcium is albumin bound, to find a true serum calcium do serum calcium and serum albumin.
Then add 0.1mmol/l for every 5g/l reduction in Albumin from 40g/l

26
Q

Vitamin D replacement

A
  • Usually tablets contain calcium and vitamin D
  • Maintainence dose of 400-1000 international units with higher loading dose
  • When kidney function is impaired it is unable to hydroxylate the calcium into Calcitrol and Alfacalcidol- these should be administered if this is the case
27
Q

How would you treat primary hyperparathyroidism

A
  • Generous fluid intake
  • Cinacalcet: mimics calcium. Binds to receptors and causes PTH levels to fall, consequently getting calcium levels to fall.
28
Q

Indications for surgery on primary hyperparathyroidism

A
  • serum calcium more than 0.25 mol/l over upper limit
  • osteoporosis OR DEXA
  • eGFR<60 or presence of kidney stones
  • AGE<50
29
Q

Investigations for primary hyperparathyroidism

A
  • Ca
  • PTH
  • Renal function
  • Vitamin D
  • 24 h urine collection of calcium
  • DEXA for osteoporosis
  • parathyroid ultrasound

endocrine (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions