Primary hyperparathyroidism, asymptomatic,
increased PTH-PTH, which will then drive the
removal of calcium from your bone, may result
So, you have, here, hypercalcemia and hypercalcuria.
There is a condition that I talked to you
about earlier where it was your hypercalc-...
Thus familial, if you remember correctly.
There’s a decrease here in phosphorus because
that excess PTH is working on the kidney and
the PCT to then flush out the phosphate.
Speaking of the PCT, the PTH is then stimulating
1-alpha-hydroxylase resulting in activation
of Vitamin D. There might be symptoms of primary
hyperparathyroidism which includes your pathologic
fractures and so forth that we talked about…
brain, depression and that particular bone
damage that’s taking place extensively is
called osteitis fibrosa cystica a.k.a. Von
Recklinghausen’s disease of the bone.
Next, what may then happen... remember we
called as the brown tumor?
Well, remember, this is not an actual tumor
that you find in your bone; it’s a fact
that you’re going to have replacement of
this cavity being caused by excess PTH activity
and osteoclasts in which you find haemosiderin
within the cavity, you call this “a brown
Yes, PTH works in the kidney to reabsorb the
calcium, but as you know, majority of your
calcium is stored in bone.
You start breaking down this bone, which PTH
will do, all these calcium gets filtered through
your glomerulus, may result in polyuria in
males and result in calcium stones.
Symptoms of hypercalcemia, what are they again?
In the brain, it will be depression and perhaps
seizures; if it’s intestine and such, then
you’re thinking about your peptic ulcer
disease of the duodenal type maybe pancreatitis
or gall stones; there might be constipation,
pancreatitis, altered mental status and peptic
Now what osteitis fibrosa cystica is is the
following: take a look at the bone here.
Find it to be very, very lucent and the image
that we’re seeing, looks like it’s a brown
tumor but it’s not, those are just cavities.
You find X-ray characterized by subperiosteal
bone resorption, extremely lucent, tapering
at the distal clavicle, salt and pepper appearance
on the skull and what that basically means
is that because of the black areas that you
would find on imaging, that means lucency,
that means a bone is being broken down, that’s
your pepper… where is the salt?... would
be the areas of the bone that is remaining.
You call that “salt and pepper”, appearance.
And these are cysts and within the cysts,
you might then develop your haemosiderin.
We now call this “brown tumor”.
The cavity is due to osteoclastic activity
intermixed with fibrous tissue with very poorly
mineralized bone and make sure you pay attention
to the haemosiderin depositing in that area
resulting in a brown-like appearance.