00:01
Our topic still continues with hypoparathyroidism.
00:03
Botched thyroidectomy… apart from where
the patient initially might have started with
primary hyperparathyroidism and there might
have been inadvertent, excessive parathyroidectomy
resulting in hypoparathyroidism.
00:17
If the patient is required to have a thyroidectomy
because of its proximity to the parathyroids
may result in excess or collateral damage
to the parathyroids rendering your patient
hypoparathyroid, hypocalcemic.
00:34
Congenital deficiency... here, you should
be thinking about DiGeorge syndrome.
00:38
You have your chromosome 22, a long arm 11
deletion, therefore third and fourth pharyngeal
pouches are missing, no parathyroids are present.
00:46
In addition, the third pharyngeal pouch responsible
for developing the inferior parathyroids,
the patient, the child is hypocalcemic; in
addition, the thymus does not form properly.
00:57
Therefore; look for a child that is suffering
from tetany, hypocalcemia; result in tetany,
muscle twitching.
01:06
In addition, there might be recurrent infection.
01:08
Usually, it will be the viral type; malformed
third and fourth pharyngeal pouches resulting
in hypoparathyroidism.
01:19
Abnormal facies, sometimes with your chromosome
22, you want to be familiar with the syndrome
congenitally that the boards love asking about
called velocardiofacial abnormalities.
01:32
The velocardiofacial abnormalities may result
in facies issue, congenital heart defects
and cognitive behavior and psychiatric problems,
autism.
01:44
Velocardiofacial issues with chromosome 22,
something that you want to know from a embryologic,
pathologic point of view.
01:54
Increased susceptibility to infection, why
is that?
Because the thymus may not be present, inadequate
education of your T-cells, therefore rendering
the patient susceptible to infection, the
child.
02:06
Other causes of hypoparathyroidism: Idiopathic, autoimmune disease
resulting in parathyroid destruction. Here’s an interesting example to keep in mind:
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy syndrome,
also known as polyglandular autoimmune syndrome type 1,
is an inherited disorder that causes hypoparathyroidism
and is associated with chronic mucocutaneous candidiasis and adrenal insufficiency.
02:37
Lastly, infiltrative diseases are a rare cause, such as hemochromatosis,
Wilson disease, granulomatous disease, or metastatic cancer.
02:48
Clinical features include the following: whenever there
is decrease in parathyroid, there will obviously
be decrease in calcium and therefore, the
muscle, the skeletal muscle is extremely sensitive
to certain tapping.
03:03
Tapping of the facial nerve may result in
contraction of muscles of the eyes, nose and
mouth and we then refer to as being Chvostek
sign.
03:13
There might be circumoral numbness or paraesthesia
of distal extremity and perhaps carpopedal
spasms, especially when there is a, let’s
say, a brachial cuff that is placed around
the arm.
03:27
Mental status changes, QT prolongation might
be seen with hypoparathyroidism and hypocalcemia;
serum calcium will be low here because there’s
decreased levels of PTH; decreased ability
to properly evacuate the phosphate from your
kidney.
03:44
So, therefore, there will be increased phosphate
levels.
03:48
In addition, because of decreased PTH in circulation,
the osteoclasts will not function as well
as they should.
03:58
And so, therefore, there will be thickening
of the bone.
04:01
The thickening of the bone, pay attention
here, we’re now referring to osteoporosis,
this is osteosclerosis and that to you should
indicate or def-defines thickening of your
bone.
04:15
Topic… hypoparathyroidism.