Enwk4- 2-2 Pinzur Hypercalcemia/hypocalcemia

Front 1

MCC of nonmalignant hypercalcemia?

MCC by?

Back 1

Primary hyperparathyroidism (HPTH)
- mcc by parathyroid adenoma (80% of cases)

Front 2

HPTH associated with what?

Back 2

MEN 1 and MEN2a

Front 3

What is net GI absorption of Ca/day

Ca is 45% protein bound... which protein is it mostly bond to?

Back 3

200mg

- mostly bound to albumin

Front 4

Primary regulator of serum calcium

What amount of serum Ca causes max secretion of this primary regulator?

Back 4

PTH

- Ca drops below 7.5 mg/dl causes max release of PTH

Front 5

for every serum albumin decrease of 1g/dl what is change in serum Ca?
How does a tourniquet effect serum Ca?

Back 5

decrease of .8mg/dl

- tourniquet causes transductino of plasma water (but not protein) into tissue which elevates total serum Ca

Front 6

In parathyroid adenoma what is MC gland effected?

Back 6

usually right inferior

Front 7

Role of pH and Ca change

Back 7

Ph. The binding of Ca to protein increases with ph. A change of 0.1 ph unit causes an opposite change of 0.12 mg/dl in the ionized Ca.

Front 8

What drugs cause hypercalcemia/

Back 8

vit D, A, lithium, thiazide diuretics, calcium- containing antacids (milk-alkali syndrome)

Front 9

One of the causes of primary hyperparathyroidism is primary hyperplasia...
Which glands are affected and which cells?
What are other cells associated and what is name?

Back 9

usually all four glands
usually seen in chief cell hyperplasia
- sometimes clear cell hyperplasia (aka wasserhelle cell hyperplasia)--> With this you will see markedly increased serum calcium levels

Front 10

What group of people tend to more frequently have primary hyperparathyroidism?
MC presentation?

Back 10

post menopausal women (show hypercalcemia)

- MC presentation is asymptomatic

Front 11

What are granulomatous causes of hypercalcemia?

Back 11

Sarcoidosis, tuberculosis and histoplasmosis elevate 1,25- vitamin D3 levels via activated monocytes

Front 12

Acute kidney failure can cause hypercalcemia how?

Back 12

Hypercalcemia may occur in the polyuric recovery phase of acute
tubular necrosis due to elevated PTH and 1,25-vit.D3 levels and
dissolution of ectopic ( usually muscle ) calcium phosphate
deposits.

Front 13

MC see in dialysis patients or women undergoing treatment for osteoporosis as cause of hypercalcemia?

Back 13

Vit D intoxication

Front 14

Milk-alkali syndrome caused by (in relation to hypercalcemia)

Back 14

caused by ingestion of large amount of Ca ( > 5g/day ) and alkali. Alkalosis increases protein binding of Ca and stimulates tubular calcium reabsorption

Front 15

3 main ways hypercalcemia may occur with malginancies?

Back 15

1. MC 2ndary to osteolytic lesions (metastatic breast, and multiple meyloma) phosphate elevated
2. Other neoplasms (lymphomas) synthesize excessive amount of 1,25 dihydroxyvitamin D... elevated phosphate
3. Ectopic production of PTH-related peptide) (Squamous, renal, bladder, ovarian cancers) secrete PTH like hormone so PTH should be depressed

Front 16

How does sarcoidosis cause hypercalcemia?
Clinically shown as?

Back 16

macrophages in granulomas synthesize 1a-hydroxylase causing hyper vit. D
- seen hilar adenopathy, rash, lymphadenopathy, EKG abnormalities

Front 17

Acute hypercalcemia steps of treatments?
What are anti-responsive steps?

Back 17

1. correct dehydration, induce calciuria with saline diuresis (w or w/o loop diureti 2 to 6L/d)
2. Institute antiresponsive therapy if doesnt work
a. First line0 pamidronate disodium 90 mg IV (bisphosphanate)
b. Adjunctive: synthetic salmon calcitonin 100-400 U
c. secondline- etidronate disodium, gallium nitrate

Front 18

When is surgery indicated for primary hyperparathyroidism?

Back 18

1. Serum Ca >11.5mg/dl
2. Nephrolithiasis
3. Compromized renal function (CrCl <70%)
4. Hyper calcinuria (>400 mg Ca/day)
5. osteoporosis (T-score < -2.5)
6. age <50 yo

Front 19

What clinical signs do you show with hypercalcemia caused by malignancy

Back 19

often weight loss, anorexia and Serum Ca levels above 15 mg/Dl (3.75 mmol/L)

Front 20

What is cause of Familial benign hypocalciuric hypercalcemia?

When would you suspect it? and how do you dx?

Back 20

mutation in parathyroid calcium receptors FBHH must be
- suspected in patients whose urinary Ca/ creatinine clearance ratio is less than 0.01 ( fasting morning spot urine collection), confirmed by finding hypercalcemia in a first- degree relative, 50% of whom carry the trait
- excluded in patients with mild asymptomatic hypercalcemia
because it requires no treatment and does not respond to subtotal
parathyroidectomy

Front 21

Clinical findings of hypocalcemia

Back 21

tingling in lips and finger tips
tetany, muscle cramps, tetany, psychosis, abnormal cardiac function (CHF, hypotension, prolongation of QT interval, ventricular conduction defects, resists Dig)

Front 22

MCC of hypocalcemia in chemotherapy pt?

Back 22

secondary to acute calcium complexation due to hyperphosphatemia caused by tumor lysis syndrome

Front 23

Most common cause of hypoparathyroidism and other main causes

Back 23

1. autoimmune
2. surgical previously removed thyroid
3. DiGeourge Syndrome-
4. Hypomagnesemia

Front 24

How does low magnesium cause hypoparathyroidism?
Causes of hypomagnesemia?

Back 24

Mg is cofactor for adenylate cyclase which activates cAMP and cAMP is required for PTH

- caused by diarrhea, aminoglycosides, diuretics, alcoholism

Front 25

If pt produces PTH but has hypocalcemia... and no renal failure what might they have most likely?
How does this type of pt present?
What are their Phosphate? D3? Vit. D?

Back 25

AD disease of pseudohypoparathyroidism- where organs are resistant to PTH
- mental retardation, short forth and fifth metacarpals
- decreased phosphate and vit. D but normal D3

Front 26

What is the knuckle, knuckle, dimple dimple sign? Pathopneumonic for?

Back 26

means short fourth and fifth digits seen in pesudohypoparathyroidism

Front 27

How does acute pancreatitis cause hypocalcemia?

Back 27

Ca is bound to FA in enzymatic fat necrosis... very poor sign

Front 28

Why does low Ca cause tetany?

What is clinical signs?

Back 28

decreased ionized Ca level which lowers threshold potential (Et) to near resting membrane potential (Em)
- it takes much less effort to activate
- thumbs adduct into palm, facial twitching after tapping facial nerve

Front 29

If pt has following features with no signs of calcium disorder its known as?
– Short stature
– Round face
– Short neck
– Short metacarpals and metatarsals (brachydactyly)
– Mental retardation

Back 29

The skeletal abnormalities in the absence of any calcium disorder - “
pseudopseudohypoparathyroidism”

Front 30

Following features with Ca disorder known as
– Short stature
– Round face
– Short neck
– Short metacarpals and metatarsals (brachydactyly)
– Mental retardation

Back 30

pseudohypoparathyroidism
- "Albrights hereditary osteodystrophy" results from kidney unresponsiveness to PTH

Front 31

First step in Differential diagnosis of hypocalcemia

Why measure albumin, pH, and Mg?

Back 31

verify true hypocalcemia measure ionized Ca
- measure serum albumin and pH to exclude pseudo hypocalcemia and acute respiratory alkalosis
- Mg- low Mg decreases PTH secretion and leads to resistance to PTH action on bone

Front 32

Hypocalcemia with high phosphorus

Back 32

rhabdomyolysis,

Front 33

low phosphorus, high PTH, low Ca most likely?

Back 33

Vit D def, pancreatitis or metastatic bone disease

Front 34

low Ca, high PTH, high phosphorus think?

Back 34

rhabdomyolysis, chronic renal insufficiency and pseudohypoparathyroidism (this results from end organ resistance to PTH)

Front 35

low Ca and low or normal PTH thinking?

Back 35

If low or normal - hypoparathyroidism is present. PTH deficiency can result from absence of functional tissue owing to surgical removal, replacement by tumor or infiltration with amyloid.

Front 36

What conditions cause decreased D3 production?
loss of D3?

Back 36

liver disease,

- accelerated loss of 25- OH D3 because of the nephrotic syndrome or abnormalities of the enterohepatic circulation.

Front 37

alkaline phosphatase levels in the following...
a. vit D def
b. renal failure

Back 37

both high

Front 38

tx of hypocalcemia?
What if acute symptomatic?

Back 38

1. Treat underlying cause
2. Ca supplementation
3. Vit supplementation
4. If acute symptomatic requires immediate tx preferred by 10-20 ml Ca gluconate (90mg Ca per 10 ml vial) at no more than 2ml/min. or CaCl (272 mg Ca per 10 ml vial)