Endocrine disorders and diabetes Flashcards
What is the normal range for blood glucose levels?
4 to 6 mmol/L
What is the key role of insulin in energy metabolism?
Insulin facilitates uptake, use, and storage of glucose
What are the main differences between type 1 and type 2 diabetes mellitus?
Risk factors, presentation, management
List modifiable risk factors for type 2 diabetes mellitus.
- Obesity
- Physical inactivity
- Hypertension
- Gestational diabetes
- Prediabetes
What are some common clinical signs/symptoms of diabetes mellitus?
Polyuria, polydipsia, weight loss
What diagnostic tests are used to screen for diabetes?
- Fasting plasma glucose
- HbA1c
How does insulin deficiency lead to symptoms associated with T1DM and T2DM?
Cells are starved of an energy source, leading to high blood glucose levels
What are the main acute complications associated with uncontrolled diabetes?
- Hypoglycaemia
- Diabetic ketoacidosis (DKA)
- Hyperosmolar hyperglycemic state (HHS)
What are the chronic complications associated with uncontrolled diabetes?
- Diabetic retinopathy
- Diabetic nephropathy
- Diabetic neuropathies
- Coronary artery disease
- Stroke
- Peripheral arterial disease
Where is visceral fat located and why is it considered riskier for health?
Located around internal organs; associated with higher health risks than peripheral fat
What is metabolic syndrome?
A cluster of conditions that increase risk for heart disease, stroke, and diabetes
What are the key actions of glucagon?
- Initiates glycogenolysis
- Increases gluconeogenesis
- Activates lipolysis
What is the primary stimulus for the release of glucagon?
Hypoglycaemia
True or False: Adrenaline can increase blood glucose levels.
True
What are the two main incretin hormones?
- Glucagon-like peptide 1 (GLP-1)
- Glucose-dependent insulinotropic peptide (GIP)
What is the primary cause of Type 1 diabetes mellitus?
Loss of pancreatic islet β cells leading to insulin deficiency
What are some characteristics of Type 2 diabetes mellitus?
- Insulin resistance
- β-cell dysfunction
- Hyperglycaemia
What is the significance of HbA1c in diabetes management?
Used to monitor long-term blood glucose control
Fill in the blank: The main stimulus for insulin secretion is _______.
[hyperglycaemia]
What is the prevalence of Type 2 diabetes mellitus in New Zealand as of 2018?
Estimated 228,000 NZs (4.7% of the population)
What lifestyle modifications are recommended for managing Type 2 diabetes?
- Weight loss
- Increased physical activity
- Dietary changes
What are some pharmacological treatments for Type 2 diabetes?
- Metformin
- DDP-4 inhibitors
- SGLT2 inhibitors
- GLP-1 receptor agonists
What is the goal of diabetes management?
Maintain blood glucose levels as close to normal as possible
What are the criteria for diagnosing metabolic syndrome?
Co-occurrence of three out of five medical conditions
What are the normal blood glucose levels in mmol/L?
4 to 6 mmol/L
Normal range for healthy individuals
What role does insulin play in energy metabolism?
Insulin facilitates uptake of blood glucose into cells, stimulates glycogen synthesis, and inhibits fat and protein breakdown.
Insulin is crucial for maintaining blood glucose levels.
What are the main differences between type 1 and type 2 diabetes mellitus?
- Risk factors: T1DM is autoimmune; T2DM involves insulin resistance.
- Presentation: T1DM usually presents in childhood; T2DM often in adults.
- Management: T1DM requires insulin; T2DM may involve lifestyle changes and medications.
What are the key diagnostic tests for diabetes mellitus?
- Fasting plasma glucose
- HbA1c
- Oral glucose tolerance test
These tests help screen, diagnose, and monitor diabetes.
How does insulin deficiency affect the body in T1DM and T2DM?
Leads to hyperglycemia and impaired glucose metabolism, causing symptoms like fatigue and excessive thirst.
Insulin deficiency disrupts normal energy utilization.
What are the main acute complications of uncontrolled diabetes mellitus?
- Hypoglycemia
- Diabetic ketoacidosis (DKA)
- Hyperosmolar hyperglycemic state (HHS)
These conditions can be life-threatening if not managed properly.
What are the chronic complications associated with uncontrolled diabetes mellitus?
- Microvascular disease
- Macrovascular disease
- Infection and impaired wound healing
Complications can affect various organ systems.
What health issues are associated with obesity?
- Type 2 diabetes
- Cardiovascular disease
- Metabolic syndrome
Obesity significantly increases the risk for these conditions.
Where is visceral fat located and why is it riskier for health?
Visceral fat is located around internal organs and is associated with higher health risks than peripheral fat.
It is linked to metabolic diseases.
What constitutes metabolic syndrome?
Co-occurrence of three out of five conditions: abdominal obesity, elevated fasting plasma glucose, elevated blood pressure, high serum triglycerides, low HDL cholesterol.
Metabolic syndrome increases cardiovascular risk.
What stimulates the release of glucagon?
Mainly hypoglycemia, along with high amino acid concentrations, stress, and strenuous exercise.
Glucagon helps raise blood glucose levels.
What are the actions of incretin hormones like GLP-1?
- Increase insulin secretion
- Decrease glucagon secretion
- Delay gastric emptying
- Reduce appetite
- Promote satiety
GLP-1 has protective effects on beta cells.
What is the prevalence of type 2 diabetes in New Zealand as of 2018?
Estimated 228,000 NZs had T2DM (4.7% of the population).
The prevalence is increasing, especially among older adults.
What are the key features of type 1 diabetes mellitus?
- Autoimmune destruction of pancreatic beta cells
- Insulin deficiency
- Rapid onset of symptoms
- Common in childhood
Type 1 diabetes has no known prevention.
What is the treatment approach for type 2 diabetes mellitus?
- Lifestyle modifications
- Weight loss
- Physical activity
- Dietary changes
- Pharmacological options (e.g., metformin)
Even small weight loss can improve control.
Fill in the blank: The main stimulus for glucagon release is _______.
hypoglycemia
True or False: Type 2 diabetes is primarily characterized by autoimmune destruction of pancreatic beta cells.
False
This characteristic is specific to type 1 diabetes.
What are the common clinical signs of diabetic ketoacidosis (DKA)?
- Polyuria
- Dehydration
- Kussmaul respirations
- Sweet breath odor
DKA is a serious complication of diabetes.
What is the goal of diabetes management?
Maintain blood glucose levels as close to normal as possible.
Requires an interdisciplinary approach.
What are the two main types of endocrine disorders?
Primary and secondary disorders
Primary disorders involve the gland itself, while secondary disorders involve the hypothalamus-pituitary system.
What is a stimulation test used for?
Testing hypofunction of an endocrine gland
A tropic or stimulating hormone is administered to test the ability of the gland to increase hormone production.
What indicates hypofunction in a stimulation test?
No increase in hormone production
An increase in hormone production indicates that the gland is functioning correctly.
What are the three main causes of endocrine dysfunction?
Hypofunction, hyperfunction, hormone resistance
These can be caused by congenital defects, tumors, or reduced responsiveness of target cells.
What is Cushing syndrome (CS) associated with?
Excessive hormone production due to over stimulation or a hormone-producing tumor
Examples include excess ACTH or adrenal tumors.
What tests are used to examine endocrine function?
Blood tests, stimulation tests, suppression tests, imaging
Imaging methods include CT, MRI, PET, and isotopic scanning.
What does a low-dose dexamethasone suppression test involve?
Administering dexamethasone to assess cortisol production
A lack of suppression in cortisol levels may indicate Cushing’s disease.
What is the primary hormone produced by the thyroid gland?
Thyroid hormone (TH)
TH affects virtually every cell in the body and is found in two forms: T4 (thyroxine) and T3 (triiodothyronine).
What are the two forms of thyroid hormone?
T4 (thyroxine) and T3 (triiodothyronine)
T4 is the major form secreted, while T3 is considered the active form.
What does TSH indicate?
Initial indication of thyroid function
It guides further testing such as serum FT4 and FT3 levels.
What is the most common cause of hyperthyroidism?
Graves’ disease
An autoimmune disease where abnormal antibodies stimulate TH release.
What symptoms are associated with hyperthyroidism?
Elevated metabolic rate, sweating, rapid heartbeats, weight loss
Exophthalmos may also occur due to tissue changes behind the eyes.
What is congenital hypothyroidism?
Thyroid hormone deficiency present at birth
It can be due to gland development defects or hormone biosynthesis issues.
What is the treatment for acquired hypothyroidism?
Replacement therapy with synthetic preparations
Levothyroxine is a common treatment.
True or False: Hyperpigmentation is seen only in patients with primary adrenal insufficiency.
True
This is linked to elevated ACTH levels in conditions like Addison’s disease.
Fill in the blank: A _______ test is used for testing hyperfunction of an endocrine gland.
suppression
It assesses whether excessive hormone production can be reduced by external stimuli.
What are the main types of endocrine disorders?
- Primary disorders: hypofunction or hyperfunction of the gland. 2. Secondary disorders: defect in hypothalamus-pituitary system.
What is hypofunction in endocrine disorders?
Diminished function due to:
* Congenital defects
* Absence of an enzyme
* Destruction of a gland
* Decline of function due to aging or medication
What causes hyperfunction in endocrine disorders?
Excessive activity due to:
* Overstimulation of the gland
* Hormone-producing tumor
What is hormone resistance?
Reduced intracellular responsiveness to hormones, e.g., type 2 diabetes.
What tests are used to examine endocrine function?
- Blood tests
- Stimulation tests
- Suppression tests
- Imaging techniques
What does a stimulation test assess?
It tests the ability of an endocrine gland to increase hormone production when a tropic hormone is administered.
What does a suppression test assess?
It evaluates if an endocrine gland can reduce hormone production in response to an external stimulus.
What is the significance of an elevated ACTH and low cortisol in a patient?
It may indicate Addison’s disease.
What is the primary metabolic hormone in the body?
Thyroid hormone (TH).
What are the two forms of thyroid hormone?
- T4 (thyroxine)
- T3 (triiodothyronine)
What is the primary cause of hyperthyroidism?
Graves’ disease.
What is the role of TSH in thyroid function tests?
It gives an initial indication of thyroid function.
What is congenital hypothyroidism?
Thyroid hormone deficiency present at birth due to various causes.
What are common causes of acquired hypothyroidism?
- Autoimmune disease (Hashimoto’s thyroiditis)
- Thyroidectomy
- Iodine deficiency
What symptoms are associated with hyperthyroidism?
- Elevated metabolic rate
- Sweating
- Rapid heartbeats
- Nervousness
- Weight loss
What is the treatment for Cushing’s disease?
Treatment options include medications, surgery, or radiation.
Fill in the blank: The ACTH stimulation test is used to assess _______ of an endocrine gland.
[hypofunction]
Fill in the blank: The Dexamethasone suppression test is used to assess _______ of an endocrine gland.
[hyperfunction]
True or False: Hyperpigmentation is a common sign in patients with primary adrenal insufficiency.
True
What is the role of the pineal gland?
Regulates sleep-wake cycles and circadian rhythms
The pineal gland secretes melatonin, which influences sleep patterns.
What is the master gland of the endocrine system?
Pituitary gland
The pituitary gland controls other endocrine glands and regulates various body functions.
What are the main functions of the endocrine system?
- Controlling growth & development
- Processes of reproduction
- Metabolism
- Maintenance of fluid & electrolyte balance
- Mobilisation of immune defences
- Stress response
These functions are essential for homeostasis and overall health.
Define aetiology.
The cause of the disorder
Aetiology is crucial for understanding the origins of diseases.
Define pathophysiology.
The physiological changes that occur due to the disorder
Understanding pathophysiology helps in diagnosing and treating diseases.
What type of hormones are amino acid-based hormones?
- Protein & peptide hormones (e.g. insulin, glucagon, GLP-1)
- Amines & amino acids (e.g. adrenaline, thyroxine)
Amino acid-based hormones are water soluble and travel in blood freely.
What are steroid hormones characterized by?
Lipid soluble
Steroid hormones, such as cortisol and testosterone, bind to intracellular receptors.
Name the three stimuli that regulate hormone release.
- Hormonal stimuli
- Neural stimuli
- Humoral stimuli
These stimuli ensure the endocrine system responds appropriately to internal and external changes.
What is negative feedback regulation in hormone production?
The production of many hormones is regulated by negative feedback
This mechanism helps maintain homeostasis by inhibiting hormone release when levels are adequate.
What stimulates the anterior pituitary gland to secrete hormones?
Hypothalamic hormones
The hypothalamus plays a crucial role in regulating the endocrine system via the pituitary gland.
What is the role of the adrenal medulla in the stress response?
Secretes epinephrine and norepinephrine
These hormones prepare the body for ‘fight or flight’ responses.
Fill in the blank: Hormone release caused by altered levels of certain critical ions or nutrients is called _______.
Humoral stimuli
Humoral stimuli directly affect hormone secretion based on blood chemistry.
What is the effect of short-term stress on blood glucose levels?
Increases blood glucose by converting glycogen to glucose
This provides immediate energy for essential organs during emergencies.
What hormone is released by the adrenal cortex in response to long-term stress?
Cortisol
Cortisol helps manage stress by regulating metabolism and immune response.
True or False: Long-term stress can lead to beneficial effects on health.
False
Prolonged stress can cause high blood pressure, muscle loss, and altered immune function.
What is the hypothalamic-pituitary-thyroid feedback system responsible for?
Regulating the body’s levels of thyroid hormones (TH)
This system ensures proper metabolism and energy regulation.
What is the definition of aetiology?
The cause of the disorder.
What does pathophysiology refer to?
The physiological changes that occur due to the disorder.
What endocrine gland is known as the ‘master gland’?
Pituitary gland.
Name three functions controlled by endocrine glands.
- Growth & development
- Processes of reproduction
- Metabolism
What type of hormones are amino acid-based hormones?
Water soluble.
How do amino acid-based hormones travel in the blood?
They travel freely and bind to cell-surface receptors.
What is an example of a steroid hormone?
Cortisol.
Fill in the blank: Hormonal stimuli cause hormone release from _______ organs.
[endocrine]
What stimulates the release of hormones in neural stimuli?
Nerve fibers.
True or False: Humoral stimuli involve changes in blood levels of ions and nutrients.
True.
What hormone do parathyroid glands secrete in response to low blood calcium levels?
Parathyroid hormone (PTH).
What is the role of the hypothalamic-pituitary-target endocrine organ feedback loop?
It regulates hormone release from anterior pituitary hormones.
What hormones are released by the adrenal medulla in response to sympathetic nervous system activation?
- Epinephrine (80%)
- Norepinephrine (20%)
What is the short-term stress response primarily designed for?
To help the body respond to short-term emergencies.
What effect does epinephrine have on blood flow during stress?
Redirects blood flow away from nonessential organs.
What hormone does the anterior pituitary release in response to corticotropin-releasing hormone (CRH)?
Adrenocorticotropic hormone (ACTH).
What is the consequence of prolonged stress response?
It may lead to high blood pressure, muscle loss, and altered immune function.
What system regulates the body’s levels of thyroid hormones (TH)?
Hypothalamic-pituitary-thyroid feedback system.
What is the role of glucocorticoids released by the adrenal cortex?
They help regulate metabolism during long-term stress.
Fill in the blank: The adrenal cortex synthesizes and releases _______ in response to ACTH.
[glucocorticoids]
What are the metabolic effects of glucocorticoids?
- Protein breakdown
- Fat breakdown
- Increase blood glucose
What is the function of mineralocorticoids released by the adrenal cortex?
They help retain sodium and water, increasing blood volume and pressure.
True or False: The hypothalamus triggers the stress response through action potentials.
True.
