endo bottom tier Flashcards
1
Q
is hypo or hypercalcaemia more common
A
hypercalcaemia
2
Q
hypocalcaemia risk factors
A
Low vit D -- Low intake ---- Dark skin ---- Reduced UV exposure: Live in an area with little sun/ work job inside etc ---- Malabosrption ---- Anti-epileptic drugs : induce enzymes that increase vit D metabolism ---- Vitamin D resistance (rare) -- Low active vit D ---- kidney/ liver issue (eg CKD) Genetic - hypoparathyroidism Radiation Mg deficiency Lactose intolerance In hospital / ICU
3
Q
causes of hypocalcaemia
A
secondary hyperparathyroidism (vit d deficiency)
- Low vit D intake
- Chronic kidney disease - no active vit D
- Liver issue - no active vit D
hypoparathyroidism
- Genetic eg Di George syndrome
- Surgical (of thyroid, lymph- damaged parathyroid)
- Radiation
- Autoimmune
- Mg deficiency
- High phosphate - from chronic kindey disease
- Primary - failure of parathyroid gland, underactive
- Secondary - resulting from parathyroidectomy/thyroidectomy surgery/ radiation/ hypomagnesemia (magnesium needed for PTH secretion)
pseudohypoparathyroidism (PTH resistance)
4
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in secondary hyperparathyroidism
A
secondary hyperparathyroidism (vit D def)
- high PTH
- low Ca
- low phosphate
- PTH appropriate
- Low vitamin D levels mean low calcium absorption in the gut
- In response, PTH levels increase
- Vit D also needed for phosphate absorption. High PTH also decreases phosphate levels
5
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in hypoparathyroidism
A
- Underactive parathyroid- not much PTH produced
- So low Ca absorption (gut), reabsorption (kidney) and resorption (bone)
- low PTH
- low Ca
- high phosphate
- PTH inappropriate
6
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in pseudohypoparathyroidism
A
- high PTH
- low Ca
- high phosphate
- PTH appropriate
- PTH resistance so PTH is ineffective at increasing calcium levels
- In response to low calcium, PTH goes up. But this does not increase calcium levels
- High phosphate as PTH is ineffective
- Associated with short stature, short metacarpals, esp 4th, and sometimes intellectual impairment
7
Q
calcitonin effect on Ca / phosphate
A
decreases Ca2+ and phosphate
8
Q
bisphosphontes effect on Ca
A
reduces osteoclast activity, resulting in reduced Ca2+ (treatment for hypercalcaemia)
9
Q
causes of tetany
A
ca deficiency K+ deficiency, Mg2+ deficiency Hyperventilation Alkalosis
10
Q
hypoalbumineamia / calcium
A
presents as hypocalcaemia - Artefact of hypoalbuminemia (calcium binds to albumin)
11
Q
hypocalcaemia presentation
A
increased muscle and nerve excitability
- cramps, spasm, tetany (similar terms, involantary contraction)
- convulsions, seizures
- paraesthesia - numbness around mouth/ extremeties
- cataracts, sight loss
- basal ganglia calcification
- fractures - undermineralised bone (vit D def secondary hyperparathyroidism)
- Trousseaus sign (inflate BP cuff- brachial artery occluded, this exacerbates low calcium causing spasm in hand/forearm –> salt bae shape)
- Chcostek’s sign (tap on facial nerves, face muscles twitch)
- dermatitis
- orientation impaired, confused
- anxious irritable irrationsal
- wheeze (muscle tone increases in smooth muscle)
- weak brittle nails
12
Q
Hypocalcaemia investigations
A
- ECG - long QT interval if severe
- bloods - low Ca, vitD, phosphate, PTH, Mg (need to produce PTH)
- eGFR - look for CKD (cause of secondary hyperparathyroidism)
- x rat - pseudohypoparathyroidism has short metacarpals (esp 4th)
13
Q
chvosteks sign
- when
A
tap on facial nerves, face muscles twitch
hypocalcaemia
14
Q
trousseaus sign
- when
A
inflate BP cuff- brachial artery occluded, this exacerbates low calcium causing spasm in hand/forearm –> salt bae shape - straight fingers, bent at knuckle, wrist flexion
hypocalcaemia
15
Q
hypocalcaemia management
A
Acute
- IV calcium (calcium gluconate)
- Monitor ECG
Chronic
- vit D supplements (vit d3 colecalciferol- still needs conversion/activation)
- Alfacalcidol = vitamin D analogue
- Calcitriol = active vitamin D
- Calcium supplements : calcium carbonate/citrate/phosphate
- Adcal = calcium + vit D3
- MgCl if hypomagnesia
16
Q
hypocalcaemia complications
A
Bone weakness/ fractures/ difficulty walking /osteoporosis Convulsions/ seizures Death if untreated Abnormal heart rhythm Parkinsonism Eye damage
17
Q
hypercalcaemia risk factors
A
Post menopausal women
Renal disease
Family history of overactive parathyroid
18
Q
causes of hypercalcaemia
A
- high vitamin D (increased Ca absorption)
- malignancy- cancer/tumour in BONE (myeloma/ secondary metastases in bone)
serum calcium high (due to bone remodelling/resorption) so low PTH (neg feedback) - primary hyperparathyroidism benign adenoma - can be ant pit/ squamous cell lung cancer, breast and renal carcinomas– produce PTH (-like substance)
- tertiary hyperparathyroidism (= renal failure)- so cannot activate vit D, so Ca cannot be absorbed
19
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in high vit D
A
- low PTH
- high Ca
- low phosphate (or high acc??)
- PTH appropriate
- high vit D –> high Ca absoprtion –> low PTH
20
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in malignancy
A
- low PTH
- high Ca
- variable phosphate
- PTH appropriate
- bone remodelling/resorption –> high calcium –> so low PTH (neg feedback)
21
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in primary hyperparathyroidism
A
- high PTH
- high Ca
- low phosphate
- PTH inappropriate
- benign adenoma (lung, breast, renal, pituitary)–> PTH (-like) –> high Ca, low phosphate
22
Q
state whether the PTH, Ca, Phosphate is low/high and if the PTH is in/appropriate in tertiary hyperparathyroidism
A
- high PTH
- high Ca
- high phosphate
- PTH inappropriate
- renal failure–> cannot activate vit D –> Ca not absorbed –> low Ca–> high PTH –> PTH stimulates gut and kidney but these sources don’t allow Ca increase here and bone resorption is only a temporary fix –> So PTH rises and gets STUCK on FULL blast –> Eventually Ca increases (he didn’t say how )
Phosphate levels high as kidneys can’t excrete it
23
Q
if a patient presents to outpatient clinic with hypercalcaemia, is it more likely to be primary hyperparathyroidism or malignancy? and why?
A
primary hyperparathyroidism
malignancy is likely to present in other ways than sole hypercalcaemia
24
Q
what must you be careful with when measuring serum calcium
A
false positive for hypercalcaemia if tourniquet left on too long or old serum sample
25
hypercalcaemia presentation
- Stones (kidney/ billiary - due to Ca2+ excess)
- moans (psychic) - confusion, coma, cognitive dysfunction, Depression, anxiety , insomnia
- groans (Abdominal)- nausea, constipation, abdominal pain, malaise
- bones - breaking down - Pain, Fractures, Osteopenia / osteomalacia. Osteoporosis
thirst and polyuria (excrete all Ca2+ in urine so thirsty and thus wee
26
hypercalcaemia investigations
- ECG - short QT interval
- bloods
- -- Serum calcium high (False positive if tourniquet on too long or old serum sample)
- -- PTH
- -- phsophate
- -- alkaline phosphate - hyperparathyroidism
- -- TSH (to exclude hyperparathyroidism)
(Urine calcium- high - to exclude this rare condition where your kidneys reabsorb calcium despite hypercalcaemia )
Renal function
- If low, may indicate tertiary hyperparathyroidism
bones
- Xray/CT/MRI - looking for malignancies
- DXA bone scan - do see effects on bone, detect osteoporosis
27
hypercalcaemia management
- Rehydrate with saline 0.9% (polyuria) - IV
- Bisphosphonates as they prevent bone resorption (reduce osteoclasts activity) (also treat osteoporosis). Eg pamidronate
- Loop diuretics to excrete some calcium
- Surgical removal if primary or tertiary hyperparathyroidism
- Chemo may help for malignancy
- Monitor Ca in serum and urine
- Steroids if malignancy or vit D excess
- Cinacalcet - inhibits PTH
28
hypercalcaemia complications
Arrhythmia
Kidney stones
Kidney failure
Osteoporosis
29
primary hyperPTH causes
Benign adenoma on parathyroid
Parathyroid gland disease
Hyperplasia of all glands
A few due to parathyroid carcinoma
30
secondary hyperPTH causes
Vitamin D deficiency
Chronic kidney disease
GI disease- malabsorption
31
tertiary hyperPTH causes
Renal failure/ chronic kidney disease
| Develops from secondary hyperparathyroidism
32
treatment for 1/2/3 hyperPTH
Primary (hyperCa)
- Surgical removal of tumour (underlying cause)/ parathyroid (if hyperplasia)
- Bisphosphonates - prevent bone resorption
- When surgery contrindicated: Cinacalecet -- reduces sensitivity of parathyroid cells to Ca2+ so less PTH secretion
- Exercise
- Avoid diuretics
- Avoid high Ca2+/ vit D intake
Secondary (hypoCa)
- Calcium correction
- Supplements given for calcium and for vit D (alfacalcidol)
Tertiary (hyperCa)
- Surgical parathyroidectomy
- Cinacalcet - reduces PTH
33
hypoPTH risk factors
```
Anterior neck surgery
Genetic - syndromes such as Di George syndrome
Radiation
Mg deficiency
Chronic kidney disease
```
34
primary hypoPTH causes
Primary : low PTH due to parathyroid gland failure
- Genetic - syndromes such as Di George syndrome
- Autoimmune
35
secondary hypoPTH causes
Anterior neck surgery
Radiation
Mg deficiency
36
pseudohypoPTH causes
- PTH resistance, so PTH is ineffective at increasing calcium levels
- In response to low calcium, PTH goes up. But this does not increase calcium levels
- High phosphate as PTH is ineffective
- Associated with short stature, short metacarpals, esp 4th, and sometimes intellectual impairment
37
pseudopseudohypoPTH causes
- Same phenotypes (short stature, metacarpals...()
- But no issue with Ca2+ metabolism -- all good
- Inherited from father
- Very rare
38
carcinoid tumour
- gender
- age
- causes
women
old
genestics /fam history
non hodgekin lymphoma
39
```
carcinoid tumour
pathophysiology
- what
- where
- secretes
```
- Carcinoid tumour = malignant Tumour secreting serotonin
- originates from enterochromaffin cells
- Tumour can be in fore/mid/hind gut - could also be gallbladder, kidney, liver, pancreas, lung etc
40
carcinoid syndrome-
when neuroendocrine tumour metastasis to liver (then products drain in to the hepatic vein)
41
carcinoid crisis
When a tumour outgrows its blood supply or is handled too much during surgery - mediators flow out
Life threatening…
- Vasodilation, caused by bradykinin
- Bronchoconstriction, caused by bradykinin
- Hypotension, caused by ACTH → increased cortisol
- Hyperglycaemia, caused by ACTH → increased cortisol
- Tachycardia , caused by sertotonin
But most tumours do not secrete hormones or compounds
42
serotonin effects
```
Bowel function - diar
Mood
Clotting
Nausea
Bone density
Vasoconstriction
Increases force of contraction and heart rate (ionotropic, chonotropic)
```
43
carcinoid tumour symptoms
```
Often asymptomatic
Pain
Weight loss
Tiredness
Weakness
Cough inc blood
Sob
Wheeze
Chest pain
palpable mass
appendicitis/ obstruction - due to GI tumours
```
44
carcinoid syndrome symtpoms
```
Bronchospasm
Fast heart rate
Diarrhea /const
Skin flushing- red face/neck
R sided heart lesions
RUQ pain
```
45
why might cardiac failure be associated with carcinoid tumour
congestive
| Due to tricuspid incompetence and pulmonary stenosis
46
carcinoid tumour investigations
Urine
- High levels of hydroxy indoleacetic acid (breakdown of serotonin)
imaging
- CXR/MRI/CT - To locate primary tumours
- Liver ultrasound - Confirm metastases
Octreoscan
- Octreotide is a somatostatin analogue
- Tumour has somatostatin receptors on it
- Octreotide is radiolabelled
- It attaches to receptors on tumour
47
carcnioid tumour management
```
Somatostatin analogues eg octreotide, lanreotide
Slow growth of tumour
Block release of tumour hormones
Surgery
radio/chemotherapy
Manage symptoms / organ damage
```
48
prolactinoma
- gender
- cause
- f>m
- benign tumour of lactotroph cells in anterior pituitary
- Could also be because of antidopimnergic drug (so suspend treatment for a few days to see if due to drug or tumour)
49
prolactinoma pathophysiology
- benign tumour of lactotroph cells in anterior pituitary
- produces prolactin
- high levels of dopamine (in order to try to inhibit it)
micro and macro types based on size. micro is more common
50
prolactinoma symptoms
```
Hypogonadism (inhibits FSH/LH) inc Infertility, decreased libido,
Menstrual irregularity, amenorrhea
Galactorrhea (mammary gland)
Headaches
Visual - bitemp hemianop
```
51
prolactinoma investigations
bloods - prolactin, gonad hormones, dopamine
imaging pituitary
52
prolactinoma management
dopamine analogue/agonist → more inhibition of release
| = cabergoline
53
prolactinoma complications
```
Infertility
Decreased libido
Visual loss
Bone loss
Pregnancy complications
```
54
pheochromocytoma causes /types and pathophysiology
Tumour of chromaffin cells in the adrenal medulla → secretes catecholamine
Familial : more noradrenaline
Sporadic: more adrenaline
55
pheochromocytoma presentation
```
Episodic
Headaches
Palpitations, tachy
Sweating
Tremor
Anxiety
Weight loss
palor
```
56
pheochromocytoma investigations
ecg/HR
BP high
urine - catecholamines and metabolites high
bloods - catecholamines (less sensitive)
57
pheochromocytoma management
- Surgery
- alpha( and beta )blocker- to reduce adrenaline
- control complication = effects of HTN (MI, stroke, renal damage etc)
