endocrine Flashcards
A complex metabolic disorder characterized by abnormally increased
blood glucose concentration caused by resistance to action of insulin,
insufficient secretion of insulin, or both.
diabetes mellitus
LT damage of diabets
failure of different organs including the eyes, kidneys, nervous
system, heart and blood vessels
An anabolic hormone secreted by the Beta cells of the Islets of Langerhans
in the pancreas
insulin
function of insulins
regulating glucose homeostasis by stimulating glucose
uptake by cells and by suppressing hepatic gluconeogenesis (body makes glucose
Out of other substances)
(+) glycogen synthesis
(+) glucose transport to muscle and adipose
(+) protein synthesis
(+) uptake of amino acids by peripheral tissues
(+) transport of Triglycerides(TG) to adipose tissue
(+) fat synthesis (lipogenesis)
what does insulin impair?
-) glycogenolysis (break down of glycogen in liver)
(-) gluconeogenesis (inhibits glucose prod)
(-) hepatic glucose production
(-) lipolysis
A 29 amino acid polypeptide hormone secreted from the Alpha cells of the
Islets of Langerhans that is stimulated by hypoglycemia
glucagon (raises blood sugar) while insulin lowers blood sugar
threshold for DM with fBG
> 126
threshold for DM with random BG test
Hgb A1C level for dx of DM
> 6.5%
what’s an OGTT test? what’s the threshold for DM?
Oral Glucose Tolerance Test (OGTT)
2-hr plasma glucose following 75 g OGTT (measure BG at 0,1, and 2 hrs)
Diagnostic 200 mg/dL
prediabets dx
FPG 100-125 mg/dL (=impaired fasting glucose IFG0
random glucose 140-199
OGTT 140-199m((impaired glucose tolerance (IGT) ))
AIC 5.7-6.4%
Reflects average level of hyperglycemia over prior 2-3 months.
Hgb A1c
hgb a1c normal level, pre diabetic level, diabetic level
6.5%
hgbA1c goal for diabetics; what plasma glucose level does it correlate with?
what criteria make a woman high risk and she should be tested early for gestational DM? (ACOG)
~Obesity
~Personal history of GDM or previous macrosomic infant
~Family history of diabetes in a first degree relative
~Polycystic ovarian disease (PCOS)
Ethnicity: AA, pacific islander, hispanic
Age: >35
)
normal region for a woman to be tested for gestational diabetes (ACOG AND ADA)
24-28 weeks
FPG in pregnancy that is GDM (according to ADA)
FPG >92, if >125, diagnosis with full blown DM
gene that is associated with huge increased risk ofDM i
HLA dr3/dr4
factors causig DM I
complex genetics (but identical twins only have 30% risk), AI, environmental (viruses? chemicals? infant feeding?)
pathophys of DM i
Multiple autoimmune mechanisms
Insulitis (infiltration of islets with lymphocytes)
Islet cell antibodies (GAD, ICA, IAA)
~90% loss of b-cell function clinical disease
SX OF dm type ii
Polydipsia, polyuria, polyphagia, wt loss
RFs for DMii
Obesity (BMI > 30) Genetic predisposition FH type 2 Metabolic Syndrome (abd obesity, low HDL, etc) Race/Ethnicity (esp native american, pacific islander, AA, hispanic GDM / child > 9 lbs Mother GDM, DM SGA infants (small gestational age)
differences between type I and II
I has AI component, type II more common among 1st degree relatives, type II more likely obese, type II often asymptomatic and have comorbidities
lab tests to distinguish type I and II
AI ab: GAD 65 most common (Glutamic acid decarboxylase (GAD) antibodies
)
why do we worry about gestational diabetes?
Increases risk of perinatal morbidity and mortality, including risk of preeclampsia, polyhydramnios, macrosomia, and malformations (though degree of risk debated)
probably pathogenesis in gestational diabets
not totally understood, but Progesterone; estrogen; human placental lactogen; other placental hormones
may have a role
etiology of maturity onset diabetes of the young
autosomal dominant genetic defect in beta cell function (often confused with type I b/c of early onset) and type II b/c can be tx’d with drugs
other etiologies of diabetes mellitius
exocrine (pancreatitis, cytstic fibrosis–kills off beta cells, pancreatectomy), severe protein/calorie malnutrition, other endocrine disorders: bushings, acromegaly, hyperandrogegism, PCOS, medications (corticosteroids, HCTZ, HIV meds, antipsychotics)
acute complications of diabetes
Diabetic Ketoacidosis (DKA)
Hyperglycemic hyperosmolar state (HHS)
Hypoglycemia due to treatment
chronic complications of diabetes
Microvascular
Retinopathy: background/proliferative
Neuropathy: peripheral/autonomic/mononeuropathy multiplex
Nephropathy
Macrovascular
Coronary artery disease
Cerebrovascular disease
Peripheral artery disease(PAD)
Combined:
Lower Extremity Complications: combination of peripheral neuropathy and PAD can’t feel foot and can’t get blood there to heal it, leads to amputations
Impotence and ED
what causes diabetic tissue damage?
hyperglycemia: repeated acute changes in cellular metabolism and LT changes in stable macromolecules (glycosylation of proteins) and accelerated by HTN and HLD
T or F: Diabetes Is a Cardiovascular Disease Risk Equivalent
t
study that demonstrated Lower risk of CVD events with intensive control (microvascular)
Diabetes Control and Complications Trial (DCCT)
study that showed these results:
Intensive diabetes therapy during the DCCT later reduced the occurrence of first CV event by 42% (p=0.018) and risk of CV death, MI and CVA by 58% (p=0.016) compared to conventional therapy
Risk reductions exceeded those of other interventions such as cholesterol and BP lowering medications.
These results confirm the benefit of “metabolic memory” of the earlier excellent control.
EDIC (after DCCT)
major results of UKPDS (UK prospective diabetes study)
significant macrovascular risk reduction when on inventional group and Decline in beta-cell function correlated with loss of response to oral diabetes medications
what did these studies prove about DM? ADVANCE, ACCORD & VA-DT Results: Intensive vs Standard Glucose Control
All 3 studies confirmed reduction in microvascular complications with better glucose control but NO no significant reduction in CVD outcomes with intensive glycemic control (once you have type II it doesn’t show reduced risk)
T or F: all diabetes need to get AIC down to
False: needs to be individualized: Certain populations (children, pregnant women, and elderly) require special considerations in pregnant women want really good control, in elderly risk of hypoglycemic events is worse than goal of preventing hyperglycemic complications
More stringent glycemic goals (i.e., a normal A1C,
Less intensive glycemic goals are indicated in patients with severe or frequent hypoglycemia, elderly, multiple comorbid illnesses
potential benefits of bariatric surgery
Weight loss, Reduced need for medications , Improved diabetes control Remission of diabetes Improvements in blood pressure, blood lipids, sleep apnea, osteoarthritis, quality of life Reduced long-term mortality
non pharm of diabetes
exercise!! diet, behavioral therapy +/- non pharm
risks of bariatric surgery
periop, anastomotic leaks, wound infxns, thromboembolism, pneumonia, Late complications including nausea, vomiting, anastamotic ulcers, internal hernias, gallstones, oxalate nephropathy, dumping syndrome, nutritional deficiencies (iron, calcium, vitamins B1, B12, D) and, postprandial hypoglycemia
who should be considered by bariatric surgery?
BMI >35 + diabetes (type II)
incretin effect
The Incretin Effect Is Diminished in Subjects With Type 2 Diabetes. Incretin effect=something is different when you give glucose IV AND you eat something (we don’t know why). When you eat something it stimulates more incretin release. Incretins also slow down gastric motility and decrease appetite. Why they give incretin to DMII.
A1C goal of GDM
comorbidities of prediabetes
obesity, CVD, dyslipiedmeia, HTN, renal failure, cancer, sleep disorders
prevention or delay of DMII in prediabetes
loss of 7% of body weight, and should increase their moderate physical activity to at least 150 min/week + behavioral counseling program. F/U counseling and maintenance
screen for pre diabetes if?
>45, or BM >25 + one of the following: Inactivity Extreme obesity 1º relative with DM Previous IGT / IFGT Associated conditions Delivery > 9# baby HTN Hyperlipidemia PCOS Acanthosis Nigricans H/O premature cardiovascular disease Prior h/o GDM
acute, severe and potentially life-threatening complication of diabetes characterized by marked hyperglycemia, dehydration, and ketoacidosis
diabetic ketoacidosis
Almost exclusively seen in Type 1 DM
DKA RFs
DMI
undx’d type 1 diabetes
Interruption of insulin therapy,
– Insulin pump failure or infusion site failure
Stress of an acute or chronic illness
Psychological problems with compliance and SBGM
Alcohol and drug addiction
DKA preciptating factors
Failure to take insulin infxn acute gastroenteritis, pneumonia pyelonephritis meningitis Acute Vascular Event: Stroke, MI, mesenteric infarction Severe emotional stress Acute renal failure
DKA sx and signs
sx: Vomiting Nausea, anorexia Abdominal pain Thirst Polyuria Weight loss Weakness Mental status changes
signs: Kussmaul respirations with fruity (acetone) breath Dehydration Warm, dry, flushed skin Hypotension Postural dizziness Tachycardia Shock CNS depression, coma
DKA labs:
BG >250
(+) betahydroxybutyrate
(+) urine and serum ketones
Arterial and venous pH 16
tx of DKA
insulin, hydration (nml saline), electrolyes
what do you always have to figure out in DKA
Precipitating factors may —the underlying cause may be what does the patient in—have to figure out why it happened!
T or F: in dKA, Total body K, Na, Mg, & P likely low despite variable serum values at presentation
T:
Initially 30% may have elevated serum potassium
due to insulin deficiency, metabolic acidosis, and hyperosmolar state
Could be dangerously high
A net total body potassium deficit exists
due to GI losses, increased renal excretion, and hyperaldosteronism secondary to dehydration (3-5 mEq/kg deficit)
how does insulin affect K?
drives it into cells
A metabolic emergency in which uncontrolled hyperglycemia induces hyperosmolar state in the absence of significant ketoacidosis.
hhs: hyperosmolar hyperglycemic state
who is affected by HHS?
type 2 usu, rare type 1. often elderly.
signs and sx of HHS
Dehydration
Sodium variable (normal 135-160)
Hypotension ( 800 mg/dL)
High serum osmolality (>330 400 mOsm/L)
Weight loss, polyuria, and polydipsia
Renal insufficiency elevated BUN (prerenal)
Lactic acidosis may also be present
tx of HHS
normal saline (slow!), insulin continuous IV, potassium (watch closely), monitor renal function
major differences between HHS and DKA
coma common in HHS, kussmaul respirations in DKA, much higher glucose in HHS, ketones, acidosis, and low bicarb in DKA, elevated BUN in HHS, type1 more common in DKA, type 2 more common in HHS