Part 24 Flashcards
Glucose Tolerance Test and what is it particularly useful in diagnosing?
- Only performed in patients who have been on unrestricted diet/physical activity for 3 days before testing, involves administration of 50-100g oral glucose administered after 10 hour fast
- Gestational diabetes
HbA1C testing
Measures 70% of glycosylated hemoglobin in blood which remains for the 120 day lifespan of the RBC (avg) (does not reflect acute increase or decrease) and therefore allows for highly accurate measure of blood glucose conc.
__% change in A1C reflects a change of about ___mg/dL in avg blood glucose
1, 30
Microalbumin and microalbumin/creatinine ratio (and what should healthy value be?)
- Microalbumin test is an early indicator of kidney failure (albumin produced in liver and should not be present in blood when kidneys functioning properly) requiring 24 hour urine collection
- Microalbumin creatinine ratio is close to a 24 hour microalbumin test regarding accuracy without requiring 24 hour collection and is thus preferred (<30:1 ratio)
When is an insulin levels ordered? (3)
- evaluate PCOS
- diagnose insulinoma
- Determine cause of hypoglycemia (order alongside c peptide to monitor endogenous insulin levels)
Why order a c peptide level in suspected diabetic patient?
Monitor insulin production by the B cells of the pancreas to determine the cause of hypoglycemia - see if body producing enough of own insulin and are insulin resistant or not
C peptide levels in type 1 vs type 2 diabetics
C peptide level will be zero in type 1 diabetics (not producing insulin), in type 2 if left uncontrolled over time will drop to zero
Actions of thyroid hormone (6)
- Increase body’s metabolic rate and O2 consumption
- calorigenic effect increasing heat production
- increase heart rate and contraction strength
- increase respiratory rate
- stimulate appetite and breakdown of carbs, fats, proteins
- turn on and off various nuclear receptors
What do the C cells (parafollicular cells) of the thyroid produce?
Calcitonin
Synthroid and armour thyroid
Artificial T4 and T3 and T4 respectively (T3 alone not very useful because it has such a short half life requiring frequent dosing intervals)
2 major plasma proteins that are responsible for transport of thyroid hormone
- Thyroid binding globulin
albumin
Only __ T3/4 can penetrate cellular membranes and exert biologic activity
Unbound
Primary hypothyroidism sees a ___ TSH, very low levels of TSH can suggest ___
elevated, hyperthyroidism
Causes of elevated serum T4 (4)
- graves disease
- toxic multinodular goiter
- toxic adenoma
- thyroiditis
Causes of decreased serum T4 (3)
- hypothyroidism
- amiodarone
- post partum transient toxicosis
Hyperthyroidism + antithyroid antibodies suggests…
Hypothyroidism + antithyroid antibodies suggests…
….Graves disease
….hashimoto’s thyroiditis
Radionuclide scanning thyroid imaging
-Use of an isotope of iodine to determine if a nodule is hyperactive or underactive based on how it takes up the iodine (almost all cancers and benign lesions are cold)
Test of choice for thyroid nodule workup
Fine needle biopsy
C peptide
A protein released in equal amounts alongside insulin into the bloodstream allowing it to be a marker of insulin production (endogenous, not present with exogenous) and release in the body
5 P’s of arterial insufficiency
- Pain
- pulseless
- paresthesias
- paralysis
- pallor
- poikilothermia (rare 6th P)
Noninvasive screening for peripheral artery disease (2) and invasive (2)
- Ankle brachial index
- ultrasound
- CTA
- MRA
__% of individuals with one amputation due to peripheral arterial disease will develop ___ on the other side within 2 years
50, gangrene
Early (2) and late sensory symptoms of diabetic foot neuropathy (5)
Early -night cramps -paresthesia Late -loss of touch -deep pain -loss of position sense -anesthesia -loss of deep tendon reflex
Charcot foot definition and mech of action
Condition causing weakening of bones of the foot frequently associated with significant nerve damage from something like a diabetic neuropathy
- denervation of small foot muscles due to neuropathy
- weakness of muscle resulting
- disarray of bony structures
- atrophy of leg and foot muscles
- altered weight distribution causes callus, ulcers, pes cavus, and charcot foot