Lab med 2 endo lecture 1

common sx constellation for adrenal insufficiency

weakness, fatigue, anorexia, loss of appetite, postural hypotension

common sx constellation for hypothyroidism

cold intolerance, dry skin, constipation, weight gain

common sx constellation for cushing syndrome

fatigue, easy bruising, striae, proximal muscle weakness, weight gain, hypertension, acne

common sx constellation for hyperthyroidism

weight loss, inc appetite, palpitations, tremor, emotional lability, diffuse hair thinning

common sx constellation for prolactinoma

galactorrhea, amenorrhea, headaches

common sx constellation for hypopituitarism

weight loss, anorexia, loss of pubic and axillary hair

common sx constellation for pheocromocytoma (every damn class lmfao)

episodic palpitations, tremor, anxiety, headaches, sweating, weightloss

common sx constellation for carcinoid syndrome

episodic flushing, palpitations, abdominal cramping, diarrhea

what might you see on a physical exam for adrenal insufficiency that may confirm your differential dx (or refute it if these things arent present)

hyperpigmentation of palms/extensor surfaces/buccal mucosa

what might you see on a physical exam for cushing syndrome that may confirm your differential dx (or refute it if these things arent present)

facial plethora, moon facies, striae, purpura, proximal muscle weakness

what might you see on a physical exam for acromegaly that may confirm your differential dx (or refute it if these things arent present)

skin tags, acral enlargement, prognathism, orthodontia, cardiomegaly, inc size of hands/feet/tongue

what might you see on a physical exam for graves disease that may confirm your differential dx (or refute it if these things arent present)

proptosis, lid lag, symmetrically diffuse thyroid enlargement, abnormal extraoccular movements

what might you see on a physical exam for hyperthyroidism that may confirm your differential dx (or refute it if these things arent present)

hyperreflexia, moist skin, thin hair, tachycardia, wide pulse pressure, flow murmur, bruit over thyroid, tremor

what might you see on a physical exam for hypothyroidism that may confirm your differential dx (or refute it if these things arent present)

hyperkeratosis, myxedema, hyporeflexia, coarse hair

what might you see on a physical exam for diabetic retinopathy/neuropathy that may confirm your differential dx (or refute it if these things arent present)

retinal microaneurysms, macular edema, motor nerve deficit, inability to detect monofilament or vibratory sensation

what might you see on a physical exam for turner syndrome that may confirm your differential dx (or refute it if these things arent present)

short stature, web neck, loss of tears, coarctation of the aorta

what might you see on a physical exam for primary ovarian failure that may confirm your differential dx (or refute it if these things arent present)

shield like chest, short 4th metacarpal

what might you see on a physical exam for hypophosphatemic rickets that may confirm your differential dx (or refute it if these things arent present)

bowing of the legs

what might you see on a physical exam for pheocromocytoma that may confirm your differential dx (or refute it if these things arent present)

orthostatic blood pressure

what might you see on a physical exam for hyperprolactinemia that may confirm your differential dx (or refute it if these things arent present)

galactorrhea

what might you see on a physical exam for midgut carcinoid that may confirm your differential dx (or refute it if these things arent present)

purple hued flushing

what is glycogenesis

conversion of glucose to glycogen for storage in the liver

what is the action of glucagon in the liver

stimulates glycogen breakdown (back into glucose)

what is the action of insulin in the liver

stimulates glycogen formation (glycogenesis)

what is gluconeogenesis

the formation of glucose form non-carb carbon sources (i.e amino acids, lactate, glycerol)

what hormones trigger gluconeogenesis

glucagon, cortisol, thyroxine (T4)

when would the body decide to do gluconeogenesis

if youre fasting long term, starvation, or not eating enough carbs

where does gluconeogenesis occur

mainly in the liver, but can also happen inn the kidney, intestines, muscles, and brain

for the purposes of this class whats considered hyperglycemia

140+

for the purposes of this class whats considered hypoglycemia

70 or less

what kind of bg test allows a direct measure of blood sugar, is convenient for pts w DM to monitor their BG, adn is optimal for infant testing

capillary blood (whole blood) aka finger stick

what color tube is used for blood sugar plasma testing

grey top tube (sodium fluoride)

what color tube is used for blood sugar serum testing

red top tube (serum separator gel tube)

when would you do CSF blood sugar testing

to see if its low due to bacterial metabolism in the csf

what kind of urine tests for we do for urine BG tests

random clean catch or 24hr total volume

what is the common feature between T1D, T2D, and Gestational DM

hyperglycemia

why does diabetes put you at risk for blindness, kidney failure, heart disease, stroke and loss of toes/feet/legs/fingers

bc hyperglycemia causes damage to smaller vessels

how often are we screening ppl w risk factors (or just age) for DM

every 3 yrs (or can do annually)

at what age are we gonna start reg DM screenings

45+

what risk factors would warrant regular DM screening under 45yo

black/asian/hispanic/native american/pacific islander ppl, delivered a baby over 9lbs, previously diagnosed w gestational DM, medical hx of HTN/high cholesterol/high triglycerides, obesity (over 120% ideal body weight, first degree relative w DM, previously high random glucose test/fasting glucose/glucose tolerance test (if not preg)

diagnostic criteria for T1D or T2D (not gestational)

A1C over 6.5, fasting glucose over 126, 2 hrs glucose tolerance test over 200, classic sx of hyperglycemia or hyperglycemic crisis

a random blood glucose test (taken any time of day but best 2hrs post meal) of 110-140 is

normal

a random blood glucose test (taken any time of day but best 2hrs post meal) of 141-199 is

prediabetes

a random blood glucose test (taken any time of day but best 2hrs post meal) of 200+

diabetes

is a random blood glucose test diagnostic

no, must confirm

a fasting blood glucose (nothing except water fro 8hrs) less than 100 is

normal

a fasting blood glucose (nothing except water fro 8hrs) 100-125 is

prediabetes

a fasting blood glucose (nothing except water fro 8hrs) 126+ is

diabetes

a 2hrs oral glucose tolerance test under 140 is

normal

a 2hrs oral glucose tolerance test 140-199 is

prediabetes

a 2hrs oral glucose tolerance test 200+ is

diabetes

an A1C 5.6 or less is

normal

an A1C 5.7- 6.4 is

prediabetes

an A1C 6.5+ is

diabetes

what is one of the most frequently performed lab tests and is done as part of the chem 7 and chem 20

random blood glucose test

is a fasting blood glucose test diagnostic

yes

what could falsely elevate a fasting blood glucose test

not actually fasting, smoking, meds, acute illness/surgery/hospitalization in the last 8wks

why would we do a fasting blood glucose test

screening for DM, monitor BG changes

a stimulation test to assess glycemic response after administration of a standard dose of glucose under standardized conditions

oral glucose tolerance test

what is the best definitive diagnostic test for DM, especially in screening for gestational DM

oral glucose tolerance test

what is teh nonpreg adult standard glucose dose for an orgal glucose tolerance test

75g glucose then 2hr test

what is the modified oral glucose tolerance test dose often used for preg pts

5og glucose then 1hr test

do you have to fast before an oral glucose tolerance test

yes

a measurement of glycated proteins in RBCs that are formed when glucose binds to hemoglobin and persist over the life span of the RBC (120 days) (aka average BG over 8-12wks)

hemoglobin A1C

what is the ADA gold standard for diagnosis and monitoring of DM

A1C test

do you need to fast before an A1C

no

what is the goal management A1C level for pts w DM

keep it under 7

what can mess with A1C levels

anything that messes w blood (transfusions, pregnancy, anemia, blood loss, meds, hemolysis, chronic liver disease, etc)

what may be the first sign of damage to tiny blood vessels in the kidney (microalbuminuria)

blood/hemoglobin in urine

what is the urinalysis for a diabetic pt checking

overall renal function

what may you see on urinalysis in a DM pt not well controlled

blood/hemoglobin (tiny vessels in kidney damaged aka microalbuminuria), glucose (reabsorption of sugar), protein (glomerular filtration damage), acidic

what is produced by the liver from breakdown of lipids to be used as a fuel source for the heart, brain, and skeletal muscle during prolonged starvation

ketone bodies

where is B-ketoacyl-CoA transferase NOT present and what does that mean

not present in the liver, which means the liver can produce these enzymes but NOT use them

accumulation of ketones in the blood

ketonemia

accumulation of ketones in the urine

ketourina (purple=positive)

what kind of DM gets DKA more

T1D

what causes diabetic ketoacidosis

low insulin levels → glucose cant get into cells → body thinks its starving, no energy → body starts glycolysis to break down glucose into pyruvate and ATP (happens in cell cytoplasm) → body cant get enough energy from glycolysis because theres no glucose IN the cells to break down → body makes ketones as a backup energy source → ketones make blood more acidic

what is glycogenolysis

breaking down glycogen into glucose in the liver

clinical features of DKA

random blood sugar over 300

blood CO2 under 40 (dec)

blood bicrab under 22 (dec)

blood ketones 5+ (ketonemia)

blood pH under 7.3 (acidosis)

anion gap over 25 (acidosis)

urine glucose (glucosuria)

urine ketones (ketonuria)

acutely ill on presentation or seen w initial T1D dx (N/V, abdominal cramps, lethargic, heart probs, coma, severe weight loss)

test for abnormal amounts of albumin in the urine compared to creatinine

albuminuria

whats considered a positive test for microalbuminuria

over 30 in 24hr urine sample on 2 occasions, marker of neuropathy/cardiovascular disease/stroke

ADA recommendations for who to screen for microalbuminemia

all T1D ppl after theyve been diagnosed 5yrs, all T2D pts when diagnosed, annually and during pregnancy

what excretes C-peptides

only kidneys

how are C-peptides made

formed by pro-insulin (along w insulin) and secreted into circulation

why would we measure C-peptides

distinguish between T1D and T2D, evaluate residual B-cell function, calculate level of insulin production

test that measurescirculating glycosylated proteins and reflects glucose control over 2-3wks and is more sensitive than A1C, ideal for shorter term glucose monitoring (no fasting needed)

fructosamine

C-peptide fasting reference range

0.78-1.89

fructosamine reference range

170-285

what antibodies may you seen in pts w T1D, especially right when diagnosed

glutamic acid decarboxylase autoantibodies, islet antigen 2, insulin autoantibodies, zinc transporter 8 autoantibodies

what can cause secondary hyperglycemia in someone who isnt diabetic

trauma/stress