At this point, we will then categorize our diarrhea.
This is an important table for you to be able to properly organize your thoughts,
of the category, of the type of diarrhea, clinical conditions and, well,
the important comments of each one of these.
Osmotic Diarrhea
As we get older, our need and requirement for calcium starts dropping.
This becomes quite evident to us because as we get older
and if we were to consume the same amount of dairy
that we maybe perhaps did once upon a time when we were young
there’s every possibility that this is going to be rapidly evacuated from the colon.
Due to the fact that as we get older
naturally speaking and physiologically speaking,
lactase in fact becomes more and more scarce.
Or you can have a patient who is actually lactase deficient.
What does that mean to you?
Remember that if you are reabsorbing your glucose from your intestinal lumen
you have to have it in the form of monosaccharide.
The type of monosaccharide that becomes the most important to you physiologically
and then here pathologically, would be glucose.
Others include galactose as well.
The combination of glucose and galactose gives you an interesting disaccharide
and that being your lactose.
And lactose, of course, being the major carbohydrate that is contained in dairy.
The reason that we’re able to metabolize our lactose so very well
is because of this very enzyme that we’re seeing, lactase.
Quickly, physiologically and biochemistry,
as we consume our carbohydrate or our dairy
we have amylase within our mouth, saliva.
It begins the digestion but obviously does not complete the full digestion.
In the stomach further, we have the acid and such which then
further breaks down a carbohydrate.
By the time we get in to our duodenum, first and second part,
which is highly, highly concentrated with fingerlike projections called microvilli
which then you can refer to as being your Brush border.
Literally, the fingerlike projections are like your brush borders.
These brush border then contains a type of disaccharidase.
Another name for your lactase would be an enzyme that breaks down disaccharide.
Be smart about how you approach your material.
Therefore, a lactase is called the disaccharidase which it does exactly
as to what the name implies which is to breakdown your disaccharide.
Which one is it when we consume milk or dairy?
Lactose.
What if your patient is lactase deficient?
Then you’ve left behind lactose, a disaccharide back in your intestinal lumen.
You’ve now created an osmotic force
which is then diffusing water out from your tissue or from the ECF
and coming in to the intestinal lumen literally drawing water in.
And take a look at how much volume you are losing.
It’s going to be large amounts of volume.
And here you have, well,
osmolar gap of being greater than 40,
stops with fasting,
and here you might find the pH to be less than 6.
Welcome to an Osmotic diarrhea: lactose intolerance.
The second type is, Secretory type of diarrhea.
The ones that you should be quite familiar with are those that are peptide like.
For example, the one type of tumor that produces too much serotonin and company
would be carcinoid.
And whenever you think about carcinoid tumor,
you should be thinking about residing within the intestine.
That’s where the carcinoid tumor begins.
So therefore the type of stool that you’re going to examine
in which you’re examining in the stool would be for your
5−Hydroxyindoleacetic acid or 5−HIAA.
It’s one type of secretory.
VIPoma, the important acronym here that you will know or should know is WDHA.
And ‘WD’ stands for watery diarrhea.
With all that diarrhea, your potassium levels would drop like crazy.
The ‘H’ stands for hypokalemia.
And then finally the ‘A’ stands for achlorydria,
but this would be a secretory type of diarrhea.
Now apart from tumors, and including gastrinoma here,
apart from tumors that also produce your secretory diarrhea,
you can have certain organisms.
For example, say that you drink contaminated water
that contains the organism, the bacteria, Vibrio cholera.
That Vibrio cholera then works upon your intestinal cell
and on the basal outer membrane causing what’s known as ADP–ribosylation,
if you remember from biochemistry.
That ADP–ribosylation is then going to insert or open up
these chloride channels in lumina membrane,
and what is it going to do?
You’ve heard of rice watery stools, this is a secretory type of diarrhea.
E. coli There is something called ETEC.
If you remember from micro, E. coli could also result in a secretory type of diarrhea.
You also have laxatives such as senna and all of these may result in secretory.
Now here, yes, it’s also a large volume stool.
However, the osmolar gap is not going to be as significant
as to what you find with osmotic diarrhea.
That is important for you to pay attention to.
And eventhough your patient might be fasting, it doesn't matter
because this is a secretory biochemical activation.
Just because you stop eating doesn't mean the diarrhea stops.
That is very dangerous.
'Cause what's your next step of management?
That's a lot of fluid loss that your patient is experiencing
so you need to make sure that you do a supportive therapy with I.V. fluids and company.
Next, we have Abnormal Motility.
And here, you should be thinking about
the Dumping syndrome that we have discussed earlier.
For example, during surgery there is every possibility that the
pyloric sphincter might be compromised.
There's increased dumping of this chyme into the intestine.
We talked about the symptoms where there might be things like hypoglycemia
and the fact that there is going to be flushing and sweating
and tachycardia and company.
With all those dumping taking place with abnormal motility,
you can only imagine that there is going to be diarrhea in fact.
Thyroid issues, increased motility.
Thyroid issues, hyperthyroidism would cause more or less diarrhea.
Whereas you see here in the paragraph, decreased motility.
Diabetes mellitus would slow things down because you might be suffering from
diabetic neuropathy.
In addition, what else may then decrease motility?
What if you had Scl–70 in fibrosis?
We talked about Scleroderma also occuring up in the esophagus.
With Scleroderma, if it's a visceral type and it's systemic,
may also cause fibrosis all over the place including the intestine.
Decreased motility, along with this hypothyroidism.
So for example if you have Hashimoto, it's primary hypothyroidism,
the patient may be suffering from constipation.
The diarrhea due to bacterial, overgrowth in syndrome of, and decreased motility.
Exudative Example for this,
inflammatory bowel disease such as Ulcerative colitis, infection.
Diverticulits is exudative.
Diverticulitis, we'll talk about that particular disease.
We begin by looking at it
by referring to diverticuli then we'll go into diverticulosis.
And at some point with diverticuli, with fecalith accumulating in there,
my goodness, it's just a matter of time before your patient
goes into a state of diverticulitis.
And that's pretty inflammatory, that's pretty exudative,
by the time the stool then comes out.
Here once again, variable quantity.
And with exudative, think of once again, Ulcerative colitis
which almost always begins in the rectum.
With all that ulceration taking place and in your stool
then you might be looking for blood.
Anorectal dysfunction
Neurologic disease, post–surgically.
Here, it's small stool volume.