Lecture 16 (Endocrine)- Exam 6 Flashcards
Anatomy for endocrine system
What are the main endocrine glands?(6)
The main endocrine glands are the pituitary, thyroid, parathyroids, pancreas, adrenals and gonads: testes and ovaries
Anatomy for endocrine system
- What do the endocrine glands do?
- Although some endocrine glands, e.g. parathyroid glands and pancreas, respond directly to what?
- These glands synthesize hormones which are released into the circulation and act at distant sites.
- Although some endocrine glands, e.g. parathyroid glands and pancreas, respond directly to metabolic signals, most are controlled by hormones released from the pituitary gland
* Anatomy for endocrine system
What is a wide variety of molecules act as hormones?(7)
- peptides, e.g. insulin
- glycoproteins, e.g. thyroid-stimulating hormone (TSH)
- amines, e.g. noradrenaline (norepinephrine)
- steroid hormones, e.g. cortisol
- estrogen
- triiodothyronine
- vitamin D
Common Clinical Symptom/Sign with DDx in endocrine disease
* Weight Gain:
* Weight Loss:
* Short stature:
* Delaneyed puberty:
- Weight gain: Hypothyroidism, polycystic ovary syndrome (PCOS), Cushing’s syndrome
- Weight loss: Hyperthyroidism, diabetes mellitus, adrenal insufficiency (Addison’s disease)
- Short stature: Constitutional, non-endocrine systemic disease, e.g. celiac disease, growth hormone deficiency
- Delayed puberty: Constitutional, non-endocrine systemic disease, hypothyroidism, hypopituitarism, primary gonadal failure
Common Clinical Symptom/Sign with DDx in endocrine disease
* Menstrual disturbance:
* Diffuse neck swelling:
* Excessive thirst:
* Hirsutism:
- Menstrual disturbance: PCOS, hyperprolactinemia, thyroid dysfunction
- Diffuse neck swelling: Simple goiter, Graves’ disease, Hashimoto’s thyroiditis
- Excessive thirst: Diabetes mellitus or insipidus, hyperparathyroidism, Conn’s syndrome
- Hirsutism: Idiopathic, PCOS, Cushing’s syndrome, congenital adrenal hyperplasia
Common Clinical Symptom/Sign with DDx in endocrine disease
* Sweating:
* Flushing:
* Resistant hypertension:
* Erectile dysfunction:
- Sweating: Hyperthyroidism, hypogonadism, acromegaly, pheochromocytoma
- Flushing: Hypogonadism (especially menopause), carcinoid syndrome
- Resistant hypertension: Conn’s syndrome, Cushing’s syndrome, pheochromocytoma, acromegaly, renal artery stenosis
- Erectile dysfunction: Primary or secondary hypogonadism, diabetes mellitus, non-endocrine systemic disease
Common Clinical Symptom/Sign with DDx in endocrine disease
* Muscle weakness:
* Bone fragility and fractures:
* Altered facial appearance:
- Muscle weakness: Cushing’s syndrome, hyperthyroidism, hyperparathyroidism, osteomalacia
- Bone fragility and fractures: Cushing’s syndrome, hypogonadism, hyperthyroidism
- Altered facial appearance: Hypothyroidism, Cushing’s syndrome, acromegaly, PCOS
Diabetes Mellitus
* The term diabetes mellitus describes what?
* It is associated with what?
- The term diabetes mellitus describes diseases of abnormal carbohydrate metabolism that are characterized by hyperglycemia.
- It is associated with a relative or absolute impairment in insulin secretion, along with varying degrees of peripheral resistance to the action of insulin.
⭐️
- What is type one and two DM?
- Type 1- Early onset, autoimmune disease of the destruction of the pancreatic beta cells leading to absence of insulin, DKA may be initial presentation in 25% with new Dx, and association with HLA DR3-DQ2 and DR4 genes.
- Type 2-Most common (>90%), usually later onset, associated with obesity, + FH. Hyperglycemia usually due to progressive loss of insulin secretion from the beta cell superimposed on a background of insulin resistance, resulting in relative insulin deficiency.
Pance Prep:
Type one DM:
* What is the cause?
* These patients require what?
* When is the onset?
* Not associated with what?
- Insulin deficiency due to pancreatic beta cell destruction
- These patients require exgenous insulin
- Onset usually under 30 yo (3/4 in childhood)
- Not associated with obesitiy
Pance Prep
Type one DM:
* What are the clinical manifestations?
- Hyperglycemia without acidosis: most common inital presentation-polyuria, polydipsia, pilyphagia
- Weight loss. Lethargy
- Diabetic ketoacidosis second most common initial presentation (more common in type 1). HHS more in type 2
- Silent (asymptomatic incidental discovery)
Pance prep
Type two diabetes:
* What is the cause?
* Likely due to what?
* Common in what age?
* What are causes of insulin resistance?
- Combo of insulin insensitiy (resistance) and relative impariment of insultin secretion (increased insulin levels early in the disease but may diminish with disease progression)
- genetic and enverimental factors especially, obestity being the greatest risk factor and decreased phyical activity
- Over 40 yo
- Insulin resistance: CHAOS-> Chronic HTN, Atherosclerosis, obestity (central), stroke
Type 2 DM
* What are the clinical manifestations?
- Most are asymptomatic
- Classic symptoms: polyuria, polydipsia, polyphagia
- Poor wound healing, increased infections.
- HHS
Diabetes Mellitus
* What are the classic symptoms? (5)
Classic symptoms of hyperglycemia include polyuria, polydipsia, nocturia, blurred vision, and weight loss.
Epidemiology: DM
* How much of the US population?
* How many people?
* Type 1 most prevalent in who?
* Less common where?
- Nearly 10% of the US population
- > 30 million people, 1.5 mil with type 1
- Type 1 most prevalent in Scandinavia – incidence rates higher in US among populations of Scandinavian descent
- Genetic component to type 1
- Less common nearer the equator
Epidemiology: DM
* Type 2- genetic and environmental factors cause what?
* What is the most important environmental factor (primary factor for insulin resistance)? ⭐️
- Type 2- genetic and environmental factors cause insulin resistance and beta cell loss
- Obesity is the most important environmental factor (primary factor for insulin resistance)
Actions of Insulin
* What stimulates insulin release?
* Transports what? where?
* Promotes what? (3)
* Lowers what?
* Stimultates what?
- Glucose and amino acids stimulate Insulin release
- Transports glucose into muscle and fat cells
- Promotes lipogenesis and storage of fat in fat cells
- Promotes protein synthesis
- Lowers hepatic output of glucose
- Stimulates glycogen synthesis
Hormonal Regulation of Blood Glucose: Glucagon
* Levels increase by two-or threefold in response to what?
* What stimulates glucagon release?
* Enhances release of what?
- Levels increase by two-or threefold in response to hypoglycemia & decrease in presence of hyperglycemia
- Protein stimulates glucagon release
- Enhances release of glucose from glycogen
Hormonal Regulation of Blood Glucose: Glucagon
* Enhances synthesis of what?
* Effect is to raise what?
* Encourages what?
* Inhibits what?
- Enhances synthesis of glucose from amino acids
- Effect is to raise blood glucose
- Encourages ketone production from FFA(free fatty acids)
- Inhibits hepatic lipogenesis
Hormonal Regulation of Blood Glucose: Epinephrine
* Released from what?
* Enhances release of what? (2)
* Effects what?
- Released from adrenal medulla
- Enhances release of glucose from glycogen
- Enhances release of fatty acids from adipose tissue
- Effect is to raise blood glucose
Hormonal Regulation of Blood Glucose: Cortisol
* Released from what?
* Enhances what?
* Serves as what?
* What does it effect?
- Released from adrenal cortex
- Enhances synthesis of glucose from amino acids or fatty acids
- Serves as insulin antagonist
- Effect is to raise blood glucose
Type 1 Diabetes
* What is it caused by?
* Insulin acts as what?
* Absolute deficiency of insulin =
- Due to destruction of pancreatic beta cells from autoantigens (type 1A) or idiopathic (rare and is type 1B)
- Insulin acts as a chemical messenger to cell to accept glucose into cell for metabolism, and is always required in the treatment
- Absolute deficiency of insulin = accumulation of circulating glucose and fatty acids
Type 1 Diabetes
* Increased levels of what?
* What are common clinical features?
* What are less common sxs?
- Increased osmolality & Increased ketones
- Common clinical features – increased urination, thirst, blurry vision
- Less common – weight loss, reduced muscle mass, postural hypotension, hypokalemia, weakness, paresthesia, anorexia, nausea, vomiting
All dependent on severity of onset – acute vs. subacute
Type 2 Diabetes
* What is it?
* Insidious onset hyperglycemia leading to what?
* What may be present?
* Many are what initally?
- Insulin resistance + impairment of insulin secretion
- Insidious onset hyperglycemia leading to uptake of glucose to liver, adipose tissue and skeletal muscle
- Thirst and increased urination may be present
- Many are asymptomatic initially