Chemistry Flashcards
SPEP - Acute inflammation
Decreased albumin
Increased Alpha 1
Increased Alpha 2
SPEP - Chronic Inflammation
Decreased albumin
Increased Alpha 1
Increased Alpha 2
Increased Gamma (polyclonal)
SPEP - Hepatic Cirrhosis
Decreased albumin
Decreased Alpha 1
Decreased Alpha 2
Decreased Beta
Beta-Gamma bridging
SPEP - Nephrotic Syndrome
Decreased albumin
Decreased Alpha 1
Increased Alpha 2
Decreased Beta
Decreased Gamma
Cushing Workup
1) 1 mg screening test
2) Low dose dex - if fails to suppress then Cushing syndrome
3) High dose dex
- If fails to suppress cortisol, then adrenal source or ectopic
- If suppresses cortisol, pituitary source (Cushing disease)
4) ACTH test
- if ectopic, high ACTH
- If adrenal, low ACTH
Anion Gap - Equation and normal
AG = Na - Cl - HCO3
Normal 3-11
Causes for Anion Gap acidosis
“MUDPILES”
Methanol
Uremia
DKA
Paraldehyde
Iron/Isoniazid
Lactic Acid
Ethanol/Ethylene glycol
Starvation/Salicylates
Acute renal failure - Pre-renal
BUN/Cr
Urine Na
Urine Osm
Kidneys trying pull everything back
***BUN/Cr > 20
Urine Na < 20
Urine Osm > 500
Acute renal failure - Intrinsic
BUN/Cr
Urine Na
Urine Osm
BUN/Cr < 20
Urine Na > 20
Urine Osm < 350
Acute renal failure - Post-renal
BUN/Cr
Urine Na
Urine Osm
Kidneys trying to flush out obstruction
BUN/Cr < 20
***Urine Na > 40
Urine Osm < 350
Three causes of hypocalcemia
1) Low PTH
2) Low Mg (which blocks PTH release)
3) Low Vitamin D
Preganancy changes
CBC
Serum electrolytes
Urine
Thyroid
Coags
CBC - dilutional RBC decrease
Electrolytes - lower serum sodium and osmolality
Urine:
GFR increases
Lower serum Cr and BUN
High urine Cr, uric acid, glucose
Thyroid:
Increased TBG, T3 and T4
Coags:
Increased fibrinogen
Decreased protein S
Opiate metabolites
- Morphine
- Codeine
- Heroin
- Oxycodone
Morphine -> hydromorphone
Codeine -> hydrocodone + morphine
Heroin -> 6-MAM -> hydrocodone + morphine
Oxycodone -> oxymorphone
PCP - False positives
Dextromethorphan
LSD - False positives
Sertraline, Amitriptyline, Verapamil
Barbituates - False positives
Phenytoin
Amphetamines - False positives
Ephedrine
Pseudoephedrine
Phenylephrine
MDMA
Lipid Measurements:
Total cholesterol, LDL, HDL, TGs
Total cholesterol - direct
(cholesterol esterase + H2O2)
HDL - direct
(precipitate out LDL ad VLDL)
LDL - calculated
(Total - HDL - TGs/5)
TGs - direct
(cleave, react glycerol with H2O2)
Barbituate - mechanism of action
Increase duration of Cl- channel opening (GABA receptor)
Benzo - - mechanism of action
Increase frequency of Cl- channel opening (GABA)
Serum osmol gap
Calculated osm = (2 x Na) + (glucose / 18) + (BUN / 2,8)
Actual osm - calc
21 hydroxylase defic
Androgens - up
Glucocorticoids - down
Mineralcorticoids - down
No movement “down”
Everything shunts to testosterone
17a-hydroxylase defic
Androgens - down
Glucocorticoids - up
Mineralcorticoids - up
No movement “right”
Shunting towards minerals (but some gluco too)
11b-hydroxylase defic
Androgens - up
Glucocorticoids - down
Mineralcorticoids - weak up
No final “down”
Only thing can make is androgens
