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Course: NCLEX-RN > Unit 8
Lesson 1: Diabetes- What is diabetes mellitus?
- What is diabetes mellitus?
- Breaking down diabetes
- Types of diabetes
- Pathophysiology - Type I diabetes
- Pathophysiology - Type II diabetes
- Diagnosing diabetes
- Treating type I diabetes
- Treating type II diabetes - Pharmacology
- Treating type II diabetes - A practical approach
- Acute complications of diabetes - Diabetic ketoacidosis
- Acute complications of diabetes - Hyperosmolar hyperglycemic nonketotic state
- Diabetic nephropathy - Mechanisms
- Diabetic nephropathy - Clinical presentation & treatment
- Diabetic retinopathy
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Types of diabetes
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Want to join the conversation?
- In type 1 diabetes, why does the immune cells, after the autoimmune disorder, damage only the beta-cells and not alpha-cells?
And i also came across delta-cells in the islets of langerhans, so is their function the production of enzymes or something else? Also are they related to diabetes in any way?(10 votes)- There are still some unresolved issues regarding autoimmune disorders and why they less affect the alpha cells and glycogen secretion than they do beta cells and insulin secretion.
The delta cells produce another hormone, somatostatin, that inhibits secretion of both insulin and glucagon. Because of this inhibition caused by over expression of somatostatin as in case of pancreatic somatostatin tumors, stomatostatinomas, 95% of the patients develop diabetes mellitus.(2 votes)
- what does diabetes have to do with the mitochondria(2 votes)
- In some diabetic patients, the size, number, and efficiency of mitochondria in the pancreatic beta cells are greatly reduced. As the mitochondria play an essential role in ATP synthesis, these factors lead to the reduced amount of ATP in the cells, which in turn interferes with the opening of ATP-sensitive potassium channels necessary for insulin secretion. The reduced secretion leads to the reduced insulin blood level causing diabetes mellitus. However, because some insulin is still produced by the pancreas, these patients are usually diagnosed as type 2, type 1.5, or inherited forms of diabetes mellitus.(5 votes)
- Can you have all 3 of the types of diabetes?(2 votes)
- Yes you can have type 1 and type 2 diabetes at the same time. You're unlikely to get diagnosed with type 2 diabetes if you already have type 1, because it's hard to measure the difference in blood sugar values, but you can still suffer from both types of diabetes simultaneously.(2 votes)
- what are the two major types of diabetes?(2 votes)
- though type one is rare but more common in children(2 votes)
- if the pancreas in unable to produce glucagon for some reason such as destruction of alpha islets, will the body remain in a constant state of hypoglycemia? Is there any condition which has this state?(2 votes)
- How does the pancreas detect an increase in glucose?(2 votes)
- How hypertension cause diabetes?(2 votes)
- Having hypertension (high blood pressure) it may be a risk factor. But If someone has type 2 diabetes and hypertension that can cause a higher risk for developing other diabetes type diseases such as retinopathy and kidney disease.(2 votes)
- I don't know how long ago this video was made, but is the "un-known trigger" known now? If yes, what is it? If not, do doctors have some ideas on what it is?(1 vote)
- Usually, the body's own immune system — which normally fights harmful bacteria and viruses — mistakenly destroys the insulin-producing (islet, or islets of Langerhans) cells in the pancreas.(2 votes)
- Can you please tell me more about hyperglycemia?(1 vote)
- I thought that low blood sugar was also associated with diabetes. No?(1 vote)
- no, your right, Low blood sugar is called hypoglycemia, which is tied with type 2 diabetes.(2 votes)
Video transcript
- [Voiceover] Diabetes mellitus
is a group of disorders that's caused by improper
function of the hormone insulin, which is secreted by the pancreas. Now, this results in disregulation of blood glucose levels in the body, specifically resulting in hyperglycemia or high blood sugar, which
is the hallmark of diabetes. Now, since diabetes is
a group of disorders, this implies that there are
multiple different conditions that can lead to diabetes
mellitus, which is true. So let's break down diabetes
into three major types. Type I, Type II, and a third category
which we'll just label as miscellaneous. Now, before we dive into
these three types of diabetes, let's briefly review how
the hormone insulin works. In response to increase
in blood glucose levels, the pancreas produces and secretes a hormone known as insulin
into the bloodstream. And this insulin acts on
cells throughout the body to remove the glucose from the bloodstream by either taking it up
to use it for energy or to store it in the form of glycogen. And as a result, the blood
glucose levels decrease. And these decreased blood glucose levels then serve as a feedback mechanism to inhibit the pancreas
from secreting more insulin. So you can see that
there are two major steps in this insulin pathway. First, insulin must be
secreted by the pancreas in response to this increasing
blood glucose level. And second, the cells throughout the body must respond to the insulin in order to carry out
its metabolic functions in order to lower the glucose levels. Now, this mechanism can be thought of as similar to that of a thermostat in an air conditioning within a home. When the temperature goes up, this is sensed by the thermostat, which then sends an electrical signal to turn on the air conditioner, which will then decrease the temperature. And as the temperature goes down, this will inhibit the thermostat from continuously keeping
the air conditioner on. And this mechanism here is gonna become very important in just a minute as we differentiate the different types of diabetes mellitus. So let's go through each of
these types individually. Type I diabetes presents
mostly during childhood. And it's caused by a
genetic predisposition plus some sort of environmental trigger. Exactly what this is isn't quite known. But the combination of these two results in an auto-immune disorder in which the immune system attacks the beta cells of the pancreas to prevent them from producing insulin. On the other hand, Type II diabetes typically, although not always,
presents during adulthood. And it's even more strongly associated with a genetic predisposition. But in Type II diabetes,
instead of this unknown trigger, the genetic predisposition is accompanied with other predisposing conditions, such as obesity or hypertension. And this combination of factors results in an inability of
these cells throughout the body to respond to insulin. Then although Type I and Type II diabetes are the most common causes
of diabetes mellitus, there are a couple other
important causes of the disease. And these include diabetes
caused by medications, known as drug-induced diabetes. And drug-induced diabetes
most commonly occurs with a group of medications that are known as glucocorticoids, which are steroid medications
most frequently prescribed to decrease inflammation
throughout the body, such as with conditions
like chronic asthma or Crohn's disease. And the other miscellaneous
cause of diabetes mellitus that's really important to mention is the diabetes that's
associated with pregnancy, known as gestational diabetes. Now, let's tie this all together to receive a better understanding of how these different types of diabetes affect this underlying insulin pathway and result in diabetes mellitus. In Type I diabetes,
this auto-immune attack on the beta cells of the pancreas prevent the production and secretion of insulin into the blood. Thus, Type I diabetes
inhibits this first step in the insulin pathway. And since it decreases
the production of insulin, it's referred to as an insulin deficiency. However, in Type II diabetes
as well as drug-induced and gestational diabetes, the pancreas continues to secrete insulin. However, it's the cells
throughout the body that are unable to
adequately respond to it. So in a sense, these mechanisms
inhibit the second step in the insulin pathway. And this is known as insulin resistance, which can be thought of as a
relative insulin deficiency. So going back to this thermostat analogy, if either the thermostat or
the air conditioner is broken, the system as a whole doesn't work. The temperature inside the house is gonna continue to rise. Similarly, in diabetes
mellitus, it doesn't matter whether the underlying mechanism
affects this first step, such as with Type I diabetes, or the second step as
with Type II diabetes, drug-induced diabetes,
and gestational diabetes. Regardless, there's gonna be
either an insulin deficiency or a relative insulin deficiency. So this pathway will not work. And the body won't be able
to decrease glucose levels. This results in an
increase level of glucose, which is known as hyperglycemia, which as I mentioned at the beginning, is the hallmark finding
in diabetes mellitus.