Now, the first primary nephritic type of glomerular
disease that we’ll take a look at is IgA glomerulopathy
or IgA nephropathy. All the same thing, aka Berger.
What I wish to bring to attention is there is
another condition in pathology that we call Wegener’s
disease. Wegener’s disease is going to be associated
with small vessel disease or vasculitis. Completely
different discussion. That’s point number one.
Many students tend to get that confused between
Berger’s and Buerger’s. They are two different
conditions. One has nothing to do with the other.
Berger has to, has to, be dealing with IgA.
This IgA is then going to deposit, I’ll tell you
in a second but before I get there this IgA
could also be found in another important disease.
That is an important differential that could also
be associated with the kidney. Do you remember
which one? What if I told you there’s IgA deposition
in the kidney, or in the glomeruli and there’s also
palpable purpura in a young child in the lower
extremities or perhaps the buttocks. That’s called
Henoch-Schonlein Purpura and a better name now
clinically, and has been for quite some time called
IgA vasculopathy. Are we clear? Be careful.
This is only nephropathy. Berger, most common
nephropathy worldwide. Meaning to say majority
of nephritic and also take a look, nephrotic 5% of
the time. So worldwide, this is the one that you
definitely want to know. Next, it affects children
and adults. Next, increased mucosal synthesis
and decrease clearance of IgA. Thus you’ll find 50%
of your population in which the IgA levels are
elevated in the serum. Next, there is focal
proliferative glomerulopathy. And this IgA
is then going to deposit on your mesangium.
May I ask you something? So therefore,
which one of the biopsy patterns would most come in
handy here, do you think? It will be the
immunofluorescence in which in the mesangium you
find green pools. Meaning to say immunoglobulin is
accumulating in the mesangium resulting in green pool
type of deposition. So mesangium IgA is what you're
paying attention to. This immune complex that
deposit to the granular immunofluorescence
it ends up being in the mesangium. You're going
to activate the complement pathway.
Complement, the alternative. Overlapping features
with Henoch-Schonlein purpura may occur.
But the difference is with IgA here and
Henoch-Schonlein, you pay attention to purpura in HSP.
Henoch-Schonlein, the purpura representing
involvement of your blood vessel.
In Berger, that is not the case. But in HSP, could
you involve the blood vessel and the kidney?
Yes, you can. What’s the immunoglobulin? AAA.
Episodic bouts of hematuria. I need you to pay
attention to the description, episodic. That is big
in medicine. You can have episodic type of events
with hypertension. That’s pheochromocytoma. You
could have episodic events of jaundice, that’s
Gilbert or Gilbert’s syndrome. You have episodic
bouts of hematuria. Higher on the differential,
you should be thinking about IgA nephropathy.
Usually following a upper respiratory tract infection.
Highlight that in your head. Hyper or upper respiratory
tract type of infection, you don’t have this latent
period. For example, say that you had sore throat
or pharyngitis. Two to four weeks later,
that would not be Berger. Two to four weeks later,
would be PSGN, with hematuria. If we’re talking days
after a sore throat or pharyngitis, that would be
Berger IgA nephropathy. Did you hear what I
just said? And how important it is based on that
history to come up with two differentials
and which one will be a more likely differential
if you had what's known as synpharyngitic.
Synpharyngitic basically means the days after a
pharyngitic episode, upper respiratory tract
infection, your patient now has developed hematuria.
Slow progression to chronic renal failure.
Only 40, 50% at a time but it’s slow progression.
Many times you can have kidney damage not
necessarily going into chronic renal failure.
Corticosteroids, decrease proteinuria.
Treat the hypertension which you must do.
Remember especially for the child,
these are things that you want to keep in mind.