DM Patho (NUR 325) Created by Diana Hallis Flashcards
What is diabetes?
A metabolic disorder characterized by hyperglycemia that results from defects in insulin secretion or action
Why is diabetes a problem?
It can cause extensive long-term damage to multiple organ systems
What are simple sugars and complex chemical units?
Carbohydrates
Where are carbohydrates broken down?
duodenum and proximal jejunum
Regulating glucose depends on the __
Liver
When we eat carbs they are broken down into glucose, and our liver does what?
extracts glucose from the blood
After our liver extracts glucose from the blood it will synthesize it into __
glycogen (store it)
If our liver detects we need sugar it will __ __
breakdown glycogen
Breakdown of glycogen aka __
glycogenolysis
__ __ extract glucose for their energy need
Peripheral tissues (all cells)
The pancreas controls our body’s fuel supply in connection with the __
Liver
The pancreas controls how much __ and __ is in the blood
glucose and insulin
The pancreas has __ and __ functions
exocrine and endocrine
Exocrine function of the pancreas:
pancreatic cells secrete directly into ducts, NOT the bloodstream
endocrine function of the pancreas:
cells secrete insulin directly into the blood stream
Where in the pancreas is insulin secreted?
Islet of Langerhans
2 types of cells in the Islet of Langerhans are…
alpha and beta cells
Alpha cells secrete __ in response to low blood sugar
glucagon
What does glucagon do?
Stimulates the liver to release stored glucose into the blood
How does the liver release glucose in response to glucagon?
Glycogenesis
What do beta cells in the Islet of Langerhans do?
produce insulin
How does insulin lower blood glucose?
It stimulates the movement of glucose into body tissues
Insulin is what stimulates your cells to be able to…
use glucose
Where is glucagon released?
Islet of Langerhans in the pancreas
Where is epinephrine released?
adrenal medulla and other chromatin tissues
Where are glucocorticoids released?
adrenal cortex
Where is growth hormone secreted from?
anterior pituitary
Together, insulin, glucagon, epinephrine, glucocorticoids, and growth hormone will create a…
counter-regulatory mechanism
Counter-regulatory mechanism prevents __ under the effect of insulin
hypoglycemia
Insulin is produced by the __ __
beta cells
Insulin stimulates the… (3 things) of glucose
Uptake, utilization, and storage of glucose
All cells need glucose, what hormone tells your body to use this glucose?
Insulin
Insulin also stimulates the liver to store glucose as __
glycogen (when the cells do not need glucose)
Insulin inhibits the breakdown of __ __
adipose tissue
Once the liver has been saturated with glycogen, insulin will promote the liver to synthesize __ __
fatty acids
In the healthy person, insulin has a __-__ effect
fat-sparing
The fat-sparing effect of insulin drives cells to use __ instead of fat for energy
carbohydrates
What happens when you don’t have enough insulin?
Can’t breakdown carbohydrates efficiently
If your body cannot breakdown carbohydrates efficiently, this will cause a decrease in __ use by the cells
glucose
If cells can’t use glucose, __ results.
hyperglycemia
When cells can’t use glucose, this causes cells to use an alternate source of energy, which is __ __
fatty acids
Decrease in insulin leads to impaired __ __
fat metabolism
Insulin deficiency increases __
lipolysis
Insulin deficiency decreases __
lipogenesis
Impaired fat metabolism causes __ __ __ in the blood
free fatty acids
Free fatty acids are an alternate energy source for when…
glucose cannot be used
Excess free fatty acids is converted to __ and __
cholesterol and phospholipids
Free fatty acids will breakdown into __
acetyl-CoA
Acetyl-CoA is used by the liver to become __ __
acetoacetic acid
Substances that is composed of the acid breakdown product acetoacetic acid are __ __
ketone bodies
Short-term complication of impaired fat metabolism is increased __ __
serum ketones
Increased serum ketones aka
ketosis
Ketosis is measured by __ and __ levels
blood and urine levels
Ketosis can cause severe __ __
metabolic acidosis
Severe metabolic acidosis can lead to __
coma
Long-term complication of impaired fat metabolism
atherosclerosis
Why does long-term impaired fat metabolism cause atherosclerosis?
Due to the increased serum lipid levels
Insulin deficiency can also lead to __
proteolysis
What is proteolysis?
protein breakdown
Proteolysis causes the body to store protein ineffectively due to…?
increased protein catabolism and cessation of protein synthesis
Proteolysis causes increased in circulating __ __
amino acids
During increased circulation of amino acids, cells can then use amino acids as an __ __ when glucose is not available
energy source
Protein catabolism = __ __
muscle wasting
Protein catabolism also happens in people who are __
starving
Why do people who are starving have protein catabolism?
they don’t have carbohydrates for an energy source
Protein catabolism leads to… (4)
1) Muscle wasting 2) multiple organ dysfunction 3) aminoacidemia 3) increased urea nitrogen (BUN)
Protein catabolism is more common in Type __ diabetics
Type 1 diabetics
Hyperglycemia increases __ __ pressure
plasma osmotic pressure
What is plasma osmotic pressure?
High blood concentration
High plasma osmotic pressure causes fluid in the tissues to shift to…
the vascular space to maintain homeostasis
When fluid shifts into the vascular space to decrease osmotic pressure, this results in __ __
cellular dehydration
Osmotic diuresis will cause __
glycosuria
Glycosuria definition
Excretion of sugar in the urine
When does glycosuria occur?
When hyperglycemia reaches a point beyond what the kidneys can reabsorb
Insulin deficiency leads to… (3 Ps!)
polyuria, polyphagia, polydipsia
Polyphagia definition
increased hunger
Polydipsia definition
increased thirst
Polyuria definition
increased urination
Why does insulin deficiency lead to polyphagia?
Catabolism of fat and protein, and also cellular starvation
What does insulin deficiency lead to polydipsia?
It’s related to increased serum osmolarity
Because of vascular osmolarity there is increased water excretion and loss of __
electrolytes such as K+, Na+, Cl-
Diabetes is either an __ or __ insulin deficiency
absolute or relative
What are the three main types of diabetes?
Type 1, Type 2, and Gestational
When is an oral glucose tolerance test used?
to test gestational diabetes
Type 1 diabetes is the most common
pediatric chronic disease
When is type 1 diabetes usually diagnosed?
around 12 years of age
Type 1 diabetes can be __
idiopathic
Type 1 diabetes is much less common than…
Type 2 diabetes
You can be diagnosed with diabetes as an __
as an adult
Type 1 diabetes is considered an __ disease
autoimmune disease
With an autoimmune disease, there is a genetic predisposition and some sort of __ __
environmental factor/trigger
Sometimes the trigger for type 1 diabetes is thought to be a __
Virus that causes your body to attack the pancreatic beta cells
Diabetes type 1 is a slowly progressive T-cell mediated disease where your T-cells destroy…
your own beta cells
__ form on beta cells and circulate in the blood and lymphatics
autoantigens
Autoantigens activate cellular and humoral immunity which destroy what?
destroy the beta cells
When beta cells are destroyed they cannot be __, resulting in.,..
cannot be regenerated, resulting in a complete lack of endogenous insulin
Type 1 diabetes is often incorrectly diagnosed as…
type 2
Type 1 diabetes has a long preclinical period with symptoms showing when….
Insulin is almost gone, which produces the hyperglycemia symptoms
The preclinical period of type 1 diabetes typical age range
6-12 years
Type 1 diabetes symptoms
Polyuria, polyphagia, polydipsia, weight loss, fatigue, frequent infections, itching, visual changes, parathesia
Genetic and __ __ responsible for type 2 diabetes
environmental factors
Risk factors for type 2 diabetes (5)
Age, obesity, hypertension, inactivity, family history
Type 2 diabetes is most likely due to __ __
Insulin resistance
Insulin resistance is where cells….?
don’t respond to insulin
With type 2 diabetes, in addition to insulin resistance there is also decreased insulin secretion. Why?
due to beta cells being overwhelmed
Sub-optimal response of insulin sensitive tissues is most likely the result of what?
Long-term obesity, because insulin is constantly being secreted into the blood stream. Cells become insensitive
Non-modifiable risk factors for type 2 diabetes
Family history, age of 45 years or higher, race/ethnicity, previous gestational diabetes
Modifiable risk factors for type 2 diabetes
Physical inactivity, obesity, hypertension, hyperlipidemia
Insulin is the key to…
letting glucose into the cells
Symptoms are not as evident in type 2 as they are in..
type 1
Symptoms for type 2 diabetes are usually vague…
nonspecific manifestations of hyperglycemia
Symptoms of type 2 diabetes
Fatigue, recurrent infections, visual changes, prolonged wound healing
Doctors usually test those at high risk for type 2 diabetes such as
Overweight, hyperlipidemia, hypertension
Type 2 diabetes: Causes impaired insulin secretion because of…
B cell exhaustion due to overuse
Type 2 diabetes: Peripheral insulin resistance because of…
Increased visceral fat
Type 2 diabetes causes increased hepatic production because of…
Impaired suppression of gluconeogensis within the liver
Another metabolic complication of type 2 diabetes
Altered production of hormones and cytokines by adipose tissue
Characterized by hyperglycemia, acidosis, and ketonuria
diabetic ketoacidosis (DKA)
DKA is more common in…
Type 1 diabetics
Acidosis can be so severe that they…
go in a coma
DKA blood sugars are in the…
400-600 range
Extremely high blood sugar (600-800), very thick blood, BUT normal pH
Hyperosmolar hyperglycemic syndrome (HHS)
HHS is more common in…
Type 2 diabetics
HHS has less profound insulin deficiency than DKA, but
more significant fluid deficiency (osmolarity)
Rapid onset, blood sugar less than 55-60
hypoglycemia
Hypoglycemia is usually related to…
medications
Hypoglycemia is common in…
BOTH types of diabetics
Patients whose blood sugar is normally in the 200 range will experience
symptoms of hypoglycemia before getting to 55-60 range
Symptoms of hypoglycemia - make sure you know these!
Pallor, sweating, increased heart rate, palpitations, convulsions, coma, tremors, anxiety, restlessness, hunger
Acute complications of diabetes (3)
DKA, HHS, hypoglycemia
Chronic complications of diabetes are typically associated with…
Poorly controlled diabetes
2 types of tissue damaged caused by chronic poorly controlled diabetes
microvascular and macrovascular
Damage to capillaries, retinopathies, neuropathies, nephropathies
microvascular tissue damage
Damage to large vessels, coronary artery, pheriphal vascular, and cerebrovascular
microvascular tissue damage
Microvascular tissue damage: Frequency and severity of lesions are proportional to…
length of time with uncontrolled diabetes or duration of the disease
Accompany microvascular disease usually in the eyes, kidneys, and nerves
Hypoxia and ischemia
Diabetes can damage capillaries causing…
capillary membrane thickening
Microangiopathy
Small vessel disease
Microvascular tissue damage can lead to
dead toes, feet, damaged nerves
Most common complication of diabetes
Diabetic neuropathy
Diabetic neuropathy related to the
metabolic and vascular factors associated with chronic high blood sugar
Chronic hyperglycemia can cause diabetic neuropathy by
Ischemia and demyelination of the nerves which causes neural changes and delayed conduction
Diabetic neuropathy causes loss of
pain, temperature, and vibration sensations
Diabetic neuropathy leads to…
ulcers, infections, and results in amputation
Diabetic retinopathy is the
leading cause of blindness worldwide
Diabetic retinopathy results from..
relative hypoxemia, damage to retinal blood vessels, red blood cell aggregation, and hypertension
Diabetic retinopathy: Small vessels become occlude and cause
infarction
Diabetic nephropathy is the most common cause of…
chronic kidney disease and end stage renal disease
Why do diabetics get diabetic nephropathy?
The glomerular basement membrane becomes thick and hard and nonfunctional (sclerosed)
What percentage of diabetic develop diabetic nephropathy?
50%
What do you need to educated diabetic patients to do?
Check their feet, know if they are feeling pain or not, get eyes checked, have kidneys monitored and watch urine output. Are you peeing?
Macrovascular problems are more common in…
Type 2 diabetes
Example of macrovascular complication of type 2 diabetes
Atherosclerosis
Diabetics are at increased risk for __
Infection
Atherosclerosis puts type 2 diabetics are higher risk for
Infection, strokes, CAD, PAD
Macrovascular complications in diabetes are thought to b caused from… (4)
Oxidative stress, endothelial dysfunction, alterations in mineral metabolism, increased cytokine production
When you have hyperglycemia your body starts to do a lot of other things such as…
Oxidative stress, inflammation, contributes to the development to atherosclerosis
Diabetics have diminished __ __ of infection
warning signs of infection
Because of the vascular damage many diabetics have, when there is an infection
WBCs can’t get there to heal it
Bacteria grow more rapidly in diabetics because
Bacteria use glucose to grow, so they can proliferate quicker
Sometimes in response to diabetes, WBCs become __ and __
become abnormal and ineffective