What's the difference?
they're not aggregated.
But if you have a bunch
of cells that aggregate
Well clinically, you no longer
call them cells, you call them cast
Are we clear?
Now there are different types of cast
Now before I begin once more
Cast, you clinically mean damage
damage damage to the kidney
I'm sorry damage where?
to the kidney.
Cast. The cells?
not so specific.
Prime example, I gave you
something like neutrophils.
Neutrophils could be found with urethritis,
cystitis, pyelonephritis, right?
But if you find WBC cast, then
that will be for, which diagnosis?
So casts are formed in
tubular, what tubular?
the urine, the nephron.
lumens in the kidney,
has to be the kidney
of protein matrix,
Now you've heard of
These are normal
They're normal components
of urine findings.
However, there are times when you would
find this in settings of excess,
Maybe something like
your multiple myeloma
Now within the Tamm-horsfall protein,
within which are entrapped cells,
debris of protein leaking
through the glomeruli
So whatever it is that is
accumulating within the urine
It then combines with your
uromodulin or Tamm-horsfall
and all of this is then going
to form a cast, an aggregate
What kind of aggregates do you want to
know, and I'll show you pictures as well
Now this could be part of normal.
And then in medicine, in
pathology, what we do as well
is the fact that you then take these
casts that either are cellular or acellular
And as we go through the various cast,
we well then take a look at
cellular, acellular type of cast
Now hyaline is a aggregation of
protein, and it's ghost like.
which means that when we take a look at
this cast, of hyaline which I'll show you
it is very, very translucent.
Like this invisible little alien
in your urine, it's amazing.
But it is a cast though,
Now, no significance truly
in absence of proteinuria.
So you could find this in a
patient who's an athlete,
who just went for
a crazy workout.
And you might find hyaline cast
because it's just normal damage
that might be taking place
in which a protein
are now aggregating.
What is my topic?
Where am I?
Now RBC cast.
Not RBC as cells.
RBC cast, so you're reading a journal,
you're reading a clinical vignette
Whatever it may be, you know you're tired,
make sure that you're paying attention
Does that have a cast
associated with it, or not?
If it has a cast associated
with it, no doubt- kidney damage
What kind of glomerulonephritis is more
having or leans towards having this cast?
Nephritic, nephritic, nephritic..
I told you nephritic now this
is the third to fourth time
that I've told you to focus on
H - hematuria, hypertension
And with that hematuria,
you're going to find RBC cast
Example of nephritic?
The most common is IgA.
Call it Berger but I would know
this as being IgA nephropathy.
Another very important one,
with nephritic would be
WBC cast. now you'd want
to be careful here.
I'm gonna give you
What does WBC mean to you,
well we all know what it is.
But there are two major types of WBCs
that are involved in kidney disease.
One would be neutrophils, the
other one would be eosinophils.
So just because you'd find a WBC cast,
the next question you ask yourself
What are these cast made up of?
If they're neutrophils, take
a look at the differential
We have pyelonephritis.
Flank pain, urinary tract infection?
Either hematogenous spread or
ascending spread, discussed in Micro.
If the WBC cast is made up of eosinophils,
then this is "an allergic reaction"
Maybe your patient is
allergic to penicillin
And has what's known as, well these allergies
in which the eosinophils causes damage
and this is called Tubal Interstitial
Nephritis or Acute Interstitial Nephritis
What kind of cast are these? They're
WBC made up of eosinophils.
The other big one too, clinically is called
atheroemboli with the eosinophils as well.
Now we take a look at
Renal Tubular Cast.
What's this mean to you?
Now, here be careful.
Look at the differential.
This is Acute Tubular Necrosis.
In a previous discussion,
what did we see?
Acute Interstitial Nephritis or
Acute Interstitial Necrosis
What's the difference?
In Acute Interstitial Nephritis or
Necrosis, the problem is the fact
that the patient was maybe allergic
to something, a drug perhaps
such as a penicillin or sulfonamide.
Once the offending agent
has been removed,
guess what, you take
care of the pathology
Completely different here.
With ATN, acute tubular
necrosis, who is dying.
The tubular epithelial
cells are dying.
What's a definition of a cast?
aggregates of your cells.
So the tubular epithelial cells are
then dying because they're undergoing
well what kind of predisposing factor or
condition result in acute tubular necrosis?
ischemia being the most common.
So say that your renal artery is undergoing
ischemia due to atherosclerosis.
At some point in time with
the ischemia taking place,
Then you're going to
cause necrosis to whom?
The tubular epithelial cells.
What are these tubular
epithelial cells going to do?
They're gonna fall into the urine.
They're dying, they're crumbling.
And as they crumble,
the walls do,
they're gonna form these
renal tubular cell cast.
Are these acellular, cellular?
Well these are once again
dead cells, they're necrotic.
The walls of the nephron are dying.
It contains lipids, cholesterol.
You're thinking about once again,
the concept that I gave you
was that when there's decreased
protein in your patient,
maybe due to nephrotic syndrome,
maybe due to cirrhosis
or maybe due to damage to
rough endoplasmic reticulum
then you find there to
be increase in lipid.
fatty cast, oval fat bodies-
found with nephrotic.
like lipoid nephrosis.
What's the most common cause of
nephrotic syndrome in a child?
Minimal change disease.
Now we'll come to a type
of acellular cast.
And it's known as
waxy, broad cast.
What's this mean?
It means that here the
aggregates that you're seeing,
What your accelular are large
and they're waxy like.
They're not hyaline.
Hyaline was acellular
too, wasn't it?
And that was an
aggregate of proteins.
But that would be insignificant in
terms of its clinical relevance.
Here however with waxy, broad
cast, completely different.
Take a look at your diagnosis ,
Maybe the sign of chronic
renal failure, refractory.
Okay these are acellular, waxy broad cast.
Put those together.