Let’s take a look at important differentials
To begin with, let’s say that your patient
began with having primary hypoparathyroidism
and there was surgery that was done that we
talked about earlier in which you remove too
much parathyroid and may result in hypoparathyroidism.
Now, you have decreased reabsorption of calcium,
thus resulting in hypocalcemia.
We’ll talk about psedohypoparathyroidism
in great detail.
In other words, this is PTH resistance.
Be careful, I am not referring to PTH related
Vitamin D deficiency, for whatever reason,
and an inadequate oral intake.
Now, what you will find to be interesting
with Vitamin D deficiency is the fact that,
remember, we had a discussion of secondary
hypoparathyroidism and the most common cause
of Vitamin D deficiency in the United Sates
is renal failure.
Now, a patient with renal failure is experiencing
Malabsorption could be a cause; end stage
liver or kidney disease for reasons we just
Inadequate production or inadequate synthesis
of calcitriol; liver, kidney in order; may
manifest as osteomalacia, obviously referring
to an adult who is deficient of Vitamin D
due to these organ injuries.
Large blood transfusion, citrate is important
for you to pay attention to in transfused
blood can bind to calcium therefore, resulting
in or rendering the patient hypocalcemic.
Remember, you need free ionized calcium for
you to have proper functioning.
If any point in time calcium is bound excessively,
your patient is considered to be hypocalcemic.
Magnesium dep-depletion is important, decreased
in PTH release… magnesium depletion.
Three major times that you want to keep in
mind - may result in the possible clinical
manifestations of seizures, long QT syndrome
and hypomagnesemia with decreased PTH release
and therefore, as a consequence, hypocalcemia.
Also, any time that there is an increased
alkalotic state, understand that now, the
calcium will be excessively bound to albumin
or increasingly bound to albumin, thus increasing
the risk of hypocalcemia.
Acute pancreatitis where calcium will then
bind to free fatty acid released by the lipase
and therefore, may result in hypocalcemia.
In acute pancreatitis, you should be very
familiar with that area that might be rather
talked... like in that is saponification.
What else may cause hypocalcemia?
Excessive tissue breakdown result in excess
calcium binding to phosphate.
Any time that you find hyperphosphatemia,
phosphate loves to bind to calcium therefore,
once again, rendering the patient hypocalcemic.
Tumor lysis syndrome, rhabdomyolysis, conditions
in which you’d find excess tissue breakdown.
Tumor lysis syndrome, two major consequences,
meaning to say that your patient is suffering
from a cancer.
Therefore, administration of therapy and chemotherapy
may then result in excess breakdown of your
So, therefore, first may result in increased
uric acid release which may result in hyperuricemia.
In addition to that increase in tissue breakdown
may then bind to calcium, all of this resulting
Rhabdomyolysis, for example, one of the rare
side effects of statin drugs used in hyperlipidemia
may result in rhabdomyolysis and thus, once
again, may bind to excess calcium.
You’ll find that in many of these differentials
of hypocalcemia that if calcium is bound,
your patient’s hypocalcemic.