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206 Cards in this Set

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How do each of the following effect t4 and t3 resin uptake levels:
Hyperthyroidism, Hypothyroidism, High levels of TBG, Low levels of TBG
Hyper-- both increased
Hypo- Both decreased
High TBG- T4 incresed, t3r decreased
Low TBG- T4 decreased, t3r increased
How do each of the following effect t4 and t-uptake levels:
Hyperthyroidism, Hypothyroidism, High levels of TBG, Low levels of TBG
Hyper- T4 incresed, t-up decreased
Hypo- T4 decreased, t-up increased
High TBG- Both increased
Low TBG- Both decreased
What is t3 resin uptake a measure of?
Amount of left over radioactive T3 after adding a set amount of radioactive T3 to Thyroid binding globulin.
What is t-uptake a measure of?
Amount of free spaces left on Thyroid binding globulin (add set amount of measurable t3, remove excess)
What enzyme is affected in Hashimoto's thyroiditis?
Thyroid peroxidase (Breaks thyroglobulin in two; t4-t3 ---> t4 + t3

Also antibody seen in Graves 80% of time.
What is the most important antibody seen in Graves' disease?
Anti TSH receptor (stimulates production)
How do we measure TSH stimulating antibodies in Graves' disease?
Grow thyroid cells in culture
Add pt. serum

Measure cAMP production
How is thyroid cancer followed post-thyroidectomy?

What if auto-antibodies are present?
Measure thyroglobulin levels (t4-t4, t4-t3 form before peroxidase). These are elevated in most thyroid cancers (papillary and follicular)

Measure titers of anti-thyroglobulin antibodies.
--Generally both are ordered in pts.
What is the most likely cause of a normal t4 (bound and free), normal tsh, and low t3?
illness- illness causes decreased peripheral conversion of t4--->t3
Cause of Normal TSH, Normal free t4, High bound t4 and t3?
High thyroid binding globulin levels:
estrogens, phenothiazines, opiates
When is ACTH production the highest? Lowest?
Upon waking

Early in sleep
What molecule can be easily measured in saliva?
Cortisol - Free cortisol crosses into the saliva and is stable for up to 1 week.
What type of lactic acidosis will cause an anion gap but will not show increased levels of lactic acid on chemistry?
Bacterial overgrowth in gut with increased production of d-lactic acid (an isomer). Traditional assays do not pick up this chemical.
What is cortrosyn and what is it used for?
A synthetic ACTH (1000x normal potency) used to look for adrenal insufficiency.
How does our body compensate for a respiratory acidosis (mechanism)?
Urinary secretion of H+ and NH4+ (ammonium)
Metyrapone blocks the production of what subtrate? What is the measurable results?
11-deoxycortisol--\\-->cortisol

Normal patients can overcome this block(increased ACTH) while pts. with imparied pituitary function cannot.
What tumors most commonly produce ACTH?
Adrenal adenoma/carcinoma

Small cell and carcinoid lung tumors
What is the difference between Cushing's syndrome and Cushing's disease?
Syndrome= increased cortisol by any method

Disease= pituitary ACTH tumor (70% of Cushing's syndrome cases)
How is urine anion gap calculated and how do you interpret the results?
(Na+) + (K+) - (Cl-) = UAG
UAG<0 in diarrhea, acetazolamide use and proximal tubular acidosis
UAG>0 in distal tubular acidosis and CRF
UAG=0 in normal
What causes skin pigmentation with addison's disease?
Melanocyte stimulating factor (an ACTH derivative)
Decreased plasma cortisol
Increased ACTH
Primary adrenal insufficiency (addison's disease)
What is the main intracellular anion?

What is the main extracellular anion?
Phosphate

Chloride
Congenital adrenal hyperplasia is caused by a deficiency of what enzyme?
What substrate accumulates?
21-hydroxylase
-low cortisol, low aldosterone

17-hydroxy-progesterone
Why do females with 21-hydroxylase definciency have ambiguous genitalia?
Accumulation of 17-hydroxy-progesterone which acts as an androgen (also salt wasting)
-mild deficiency shows hirsutism and irregular periods after puberty
Why with certain assays are sodium levels falsely lowered in hyperlipidemia
Fat does not contain sodium. When the device measures sodium/volume (vs. electrical current), you see falsely lowered values.
Hypertension, hypokalemia
Decreased renin
Increased aldosterone
Primary hyperaldosteronism
Since catecholamines change too much throughout the day, what test is used to indirectly measure catecholamines?
Urine or plasma metanephrines (fractionated)
VMA is a measure of total metanephrines (epi + nor) - may not be elevated in epi tumor.
What genetic abnormality is associated with a worse prognosis in Neuroblastoma?
N-myc amplification
How is neuroblastoma followed?
Levels of VMA and HVA (dopamine derivative)
Prolactin production is inhibited by what feedback mechanism?

Causes?
Dopamine

Pituitary adenoma (75%)
Stalk compression (15%)
Drugs, other
When are growth hormone levels the highest?
During sleep or acute stress
What is the effect of Growth hormone on the liver?
Produces IGF-1 which promotes bone growth (IGF-1 can be used as a measure of GH levels).
With excess Growth hormone production, what can be used to potentially suppress levels to check for tumor?
Glucose- test 1 hour after oral glucose load, failure to suppress in tumors
What is best test to check for/follow growth hormone levels?
IGF-1 (produced by liver in response to GH)
What is the primary feedback on FSH?

What is the primary feedback on LH?
Inhibin (seritoli cells)

Sex steroids (estrogen/progesterone)
(leydig cells)
What hormone stimulates spermatogenesis?
FSH
What hormone stimulates testosterone production?
LH
What enzyme converts testosterone in dihydrotestosterone in the periphery?
5 alpha reductase

(inhibitors used for cancer and BPH)
Know this!
Progesterone dominant after ovulation
Estrogen dominant before ovulation
Fall in estrogen is the cause of LH surge
What are the substrates measured in serum HCG vs. urine HCG
Serum assay uses antibody to the beta-subunit
Urine assay uses antibody to the beta-core fragment
What is a good test for adrenal androgen overproduction?

Ovarian overproduction
DHEA-S
Dehydroepiandrosterone bound to sulfate

Testosterone
21-hydroxylase deficiency with build up of 17-OH progesterone is the most common cause of congenital adrenal hyperplasia; what is the second most common cause?
11-hydroxylase deficiency with build up of 11-deoxycortisol (also causes hypertension)
When serum calcium levels are low, what happens to PTH levels?
Increased
What effect does PTH have on the kidney?
Blocks the reabsorbtion of phosphate and bicarbonate (HCO3)
----> less complexed/bound calcium
----> also by decreased pH
What is the reaction of vitamin D in the liver?
Hydroxylated by 25-hydroxylase to 25-hydroxycholecalciferol
25(OH)D
25(OH)D is the most often measured vitamin D form
What is the reaction of vitamin D in the proximal tubules?
1 alpha hydroxylase (activated by parathyroid hormone) converting 25-hydroxycholecalciferol to 1,25 dihydroxycholecalciferol (calcitriol, note the 3 -OH groups) 1,25 (OH)D
What is a major interference for measuring total calcium by colorimetric assay?
Gadolinium (MRI)
Most hypercalcemia due to tumor is caused by production of Parathyroid related protein (PTHrP); what tumors commonly produce PTHrP?
Squamous cell carcinoma (anywhere)
Breast
RCC
(1/3rd of all cases)
How can sarcoidosis causes hypercalemia?
Production of calcitriol (also some lymphomas)
What is the effect of low magnesium (hypomagnesemia) on calcium?
Hypocalcemia (needed for parathyroid hormone?)
What two antibodies are seen in Hashimoto thyroiditis?
anti-microsomal
anti-thyroglobulin
What should be considered with a low TSH but normal T4?
Thyrotoxicosis- measure free t3 levels to see if high
What is the effect of amiodarone on the thyroid?
Depends. Contains lots of iodine so causes hyperthyroidism in iodine-poor areas. It is toxic to the thyroid so causes hypothyroidism in iodine-rich areas.
How does Vmax relate to substrate concentration
1/2 Vmax=[S]
Does a small Km mean fast or slow reactions?
The smaller the Km, the faster the reaction.
On a Lineweaver-Burk plot, an increased X-intercept (slope) without change in the Y intercept means what?
1/Vmax= Y-intercept, therefor no change

Slope and X-intercept are proportional to Km, so increase slope means increase Km ---> competitive inhibitor
What does a non-competitive inhibitor look like on a Lineweaver-Burk plot?
Decreased V-max ---> increased Y-intercept
Km unchanged
review
Which enzyme is more specific for liver damage, ALT or AST
ALT - Also found in kindey in lesser quantities in muscle

AST- Kindey, Muscle
Why is AST more elevated in alcoholic liver
Pyrodoxine (B6) is co-enzyme for production of both but ALT is more dependent on it. Also there is mitochondrial AST which can be release with damage.
LD (lactate dehydrogenase) has five isoenzymes. Where are each found?
LD1- Heart, RBC's, Renal cortex
LD2- Heart, RBC's, Renal cortex
LD3- Lung, Pancrease, plts, lymphs
LD4- ------
LD5- Liver, Muscle, Prostate
What LD marker is normally at the highest level?
LD2
What does an LD1/LD2 flip mean?
LD1>LD2
Heart attack, hemolysis or renal cortex necrosis
Elevated L1 and L5
Heart attack with centrilobular necrosis from congestion
Alkaline phosphatase comes from what 3 major sources?
1 minor
Liver (biliary tract disease)
Bone (osteoblastic activity)
Placenta/germ cell (pregnancy/germ cell tumor)
Minor: intestinal disease of the ileum
Why are alkaline phasphatase much higher in children?
Bone growth and repair, secreted by osteoblasts

-Also elevated in bone disease or fracture
If alkaline phosphatase is elevated but the source is unclear, what other enzyme would indicate biliary tract origin?
GGT
Which hepatitis viruses are RNA viruses? DNA?
RNA= A, C and D
DNA- B
Antimitochondrial autoantibodies are elevated in what disease?
Primary biliary cirrhosis
-destruction of intrahepatic bile ducts
Smooth muscle autoantibody and anti-LKM are elevated in what disease?
Autoimmune hepatitis
What enzyme converts unconjugated bilirubin to conjugated bilirubin?
UDP-glucuronyl transferase
-deficient or absent in some newborns, congenitally in Crigler-Najjar syndrome and Gilberts
UDP-glucuronyl transferase is absent in what disorder?
Crigler-Najjar syndrome

-it is decreased in gilbert's
What is effected in Dubin-Johnson syndrome?
Inability to secrete conjugated bilirubin out of hepatocytes into the bile.
What is the rate-limiting step in bilirubin conjugation?
Transfer of the conjugated bilirubin into bile duct, thus hepatitis gives you conjugated bilirubinemia
Indirect and direct bilirubin refer to what?
Reflection of the methodologies used to measure the bilirubin
Indirect = Unconjugated
Direct= Conjuaged
Total can be measured
How is bilirubin converted to urobilinogen?
By the intestinal flora
How does the diazo-colorimetric method work?
Formation of a colored dye when bilirubin reacts with a diazo compound. Alcohol (an accelerator) is added to allow the unconjugated to react. Thus direct and total are measured.
Other then diazo-colorimetric rxn, what other method can be used to measure bilirubin?
Direct spectrophotometry
absorbance at 455 nm
-only measures total bilirubin
What can be used as a longer term indicator of elevated conjugated hyperbilirubinemia?
delta-bilirubin, conjugated bilirubin covalently bound to albumin (not excreted)
what is the absorbtion spectrum of NADH?
340 nm
what is the difference between a noncompetitive and uncompetitive inhibitor
Noncom. binds enzyme away from the binding site, thus only decreasing Vmax. uncom. binds the enzyme with the substrate, thus decreasing Vmax and Km
What is the effect of renal failure on AST and ALT levels?
Both are decreased
What is the effect of heat/urea inhibition on bone and placental Alk phosphatase isoenzymes?
Bone isoenzymes are inactivated (burns), placental isoenzymes (persist)
Why is phototherapy not helpful in hyperbilirubinemia due to Dubin-Johnson syndrome?
Dubin-Johnson syndrome is a conjugated hyperbilirubinemia; phototherapy only converts unconjugated bilirubin
Breast milk jaundice generally occurs how long after birth?
>1 week
Congenital enzyme definiciencies generally present themselves with jaundice how long after birth?
>1 week
True or False
PT levels correlate with degree of hepatic injury? AST? ALT? Bilirubin?
PT is the best indicator of prognosis with hepatic injury(>4.0 = bad) bilirubin of >15 is bad; AST and ALT are poor markers and do not correlate well with degree of injury
Electrophoresis for salivary and pancreatic enzymes show what pattern?
There are 6 isoenzymes. Salivary move the farthest, while pancreatic are the slowest.
What inhibition test/substance can be used to differentiate salivary and pancreatic amylase?
Salivary amylase is inhibited by "triticum vulgaris" a wheat germ lectin.
Pancreatic amylase is not.
Why are amylase levels not elevated in 10% of patients with pancreatitis?
This is due to pts. with hypertriglyceridemia associated pancreatitis. Triglycerides interfere with the amylase assay.
True or False
Serum amylase levels correlate with severity of pancreatitis?
Lipase?
False
False
What is the result of Macroamylasemia (Ig-amylase complexes) on serum and urine amylase levels respectively?
Serum- markedly elevated
Urine- Normal
What are the advantages of lipase over amylase to measure pancreatitis?
They both rise within hours, but amylase drops within 2 days while lipase drops within 2 weeks. Lipase is more specific. Lipase is less effected by renal clearance.
What is the defect in Rotor syndrome?
Decreased hepatic glutathione-S-transferase levels
What enzyme is elevated in Sarcoidosis?
ACE (angiotensin converting enzyme)
What isoenzymes of Creatine kinase travel the furthest on electrophoresis?

Which hump is elevated with MI?
BB followed by MB followed by MM

MB is elevated with MI (middle peak)
The MB isoenzyme of CK can be separated (by electrophoresis) into two peaks, M-lys-B and M-B. Which is elevated in MI?
The M-lys-B is elevated in MI. It travels further on electrophoresis making a distinct double peak when present.
3 types of troponin are are found on actin; which two forms are elevated in MI?
C - I - T are the 3 forms
I and T are elevated in MI
How long does it take for troponins (I and T) to elevate after MI?

Myoglobin? CK-MB?
4-6 hours

1.5, 1.5
How long does myoglobin stay elevated after MI?
CK-MB isoforms?
Troponin T?
Tropoinin I?
12 hours
2 days
2 weeks
5 days
You have a suspicion of a repeat MI but don't have a previous troponin, what test would be helpful?
CK-MB isoform will only be elevated for 2 days so measuring this could demonstrate a repeat MI
Are troponins elevated with skeletal muscle damage/trauma?

CK-MB?
No

Yes
Can troponins be used to detect unstable angina?
Yes, a borderline elevated troponin indicates angina however the sensitivity and specificity aren't great. Troponins can also be elevated in renal disease and infer a worse prognosis.
ProBNP gets cleaved into NT-proBNP and BNP; how is this useful?
NT-proBNP rises more with heart failure, has a longer half-life and is not interfered with when synthetic BNP is administered
Where is Lipoprotein lipase located and what is its function?
Produced by adipocytes and muscle cells. Sits at luminal side of capillary. Releases Triglycerides from Chylomicrons -->remnant and VLDL--> IDL. The resulting monoglycerides and free fatty acids are used by the cells
Where does VLDL come from and what is its function.
Produced in Liver. Is composed of much triglycerides which can be released with Lipoprotein lipase to cells and thus forming IDL.
What happens to IDL after it is made (VLDL ---LPL---> IDL)?
Rapidly metabolized by liver OR converted to LDL via hepatic lipase
After LDL is made from IDL via hepatic lipase, what happens to it.
It is either metabolized by the liver or its cholesterol component is used by cells (esp. gonads and adrenals).
OR scavenger receptors in subendothelial spaces ---> athrosclerosis
What is the function of HDL?
Transport of cholesterol from tissues to the liver
LDL, ILD and to a lesser extent VLDL are associated with atherosclerosis; which is associated with hypertriglyceridemia?
VLDL, this makes sense because VLDL is the main carrier of triglycerides from the liver to tissues.
Which Fredrickson phenotypes show high triglycerides?
1, 4 and 5
1- elevated chylomicrons
4- elevated VLDL
5- elevated chylomicrons and VLDL (1+4=5)
Which Fredrickson phenotypes show elevated LDLs?
2a (common)
Which Fredrickson phenotypes show elevated "calculated" LDL and elevated triglycerides?
2b and 3, the triglyceride component of 2b is from elevated VLDL while the triglyceride component of 3 if from IDL
What does type 1 hypercholesterolemia look like in a test tube?
Elevated triglycerides (chylomicrons) so you get a water/oil layer with the chylos on top. (Very rare)
What does type 2a hypercholesterolemia look like in a test tube?
Clear
What does type 2b hypercholesterolemia look like in a test tube?
Has elevated LDL (calculated) and triglycerides(VLDL) thus ----> clear or cloudy
What does type 4 hypercholesterolemia look like in a test tube?
Elevated triglycerides (VLDL) so you get a turbid vile. (common)
What does type 5 hypercholesterolemia look like in a test tube?
Elevated triglycerides (chylomicrons and VLDL) so you get a turbid vile + an oil/water layer. (uncommon)
What does type 3 hypercholesterolemia look like in a test tube?
The elevated triglycerides are due to the presence of increased IDL --->Usually cloudy
What are the causes (3) for type 1 hyperlipidemia?
Increased chylomicrons---> LPL deficiency, LPL antibody (lupus), apo CII deficiency

-Both deficiencies are AR and rare
What are the causes for type 2 (a and b) hyperlipidemia?
Familial -defective LDL receptor
Familial combined- too much apo B
hypothyroidism --> regulator of LDL expression
What should be the LDL levels in someone with hypothyroidism?
Graves?
Increased LDL levels because the thyroid regulates production of the LDL receptor in the liver.
Graves= decreased
What is the genetic defect in type 3 hyperlipidemia?
Homozygous Apo E2/E2
Which apo E is associated with alzheimer's disease?
Apo E4
What are some causes of type 4 hyperlipidemia?
Any disease with decreased insulin action such as... obesity, diabetes, beta blockers
What are some causes of type 5 hyperlipidemia?
Anybody with a combination of causes of type 1 + type 4 can progress to type 5
What is abetalipoproteinemia?
AR, deficient production of apo B. Everything except HDL have apo B, so all but HDL are markedly lowered. ---> fat malabsorption, acanthocytosis and neurologic abnormalities (b/c fat malabsorption).
How do you estimate VLDL?
Triglycerides/5, formula is valid up to 400
How do you calculate LDL?
=Total chosesterol - (HDL +VLDL)
or
=Total cholesterol - (HDL + Triglyerides/5)
Name an acute phase reactant that causes hypercoagulability?
Factor 8 and fibrinogen (also due to activation of platelets)
Manose binding lectin is an acute phase reactant; what is its function?
Part of immune system; binds/recognizes foreign bacterial particles and activates complement
Chronic inflammatory disease with cardiomyopathy, enlarged liver and tongue.
Serum amyloid A is an acute phase reactant that can cause amyloidosis in inflammatory diseases.
Name 4 proteins that decrease with stress (negative acute phase reactants)?
Retinol binding protein
Transthyretin (carrier of T4)(called pre-albumin due to its place on electrophoresis)
Albumin
Transferrin
Why is electrophoresis done on serum and not plasma?
Fibrinogen (between beta and gamma) - can also show up in "serum" if line is anticoagulated -->fibrinogen present
How does immunoelectrophoresis work?
Antigen and antibody are place opposite each other and migrate toward each other forming a band
How do you interpret IEP (immunoelectrophoresis)?
Each antibody has a control (normal human serum, NHS) and the pt. sample. Look for symmetry. Peplaced by immunofixation electrophoresis (IFE)
What is found in the pre-albumin region on serum protein electrophoresis (SPE)?
Retinol-binding protein
Transthyretin - T4 transport

-Both are negative acute phase reactants
What is found in the alpha-1 region on serum protein electrophoresis (SPE)?
alpha-1 anti trypsin - protease inhibitor
HDL, Thyroxin binding globulin- T4/T3
transcortin- AKA cortisol binding glob.
prothrombin- clotting (plasma only)
What is found in the alpha-2 region on SPE?
Alpha-2 macro globulin- protease inhibitor
haptoglobin- hgb transport after hemolysis
ceruloplasmin- redox, contains CU ion
What is found in the beta region on SPE?
transferrin- Fe3+ transport
hemopexin- hgb transport after haptoglobin is used up
LDL, C3, IgA, fibrinogen (plasma)
Name 2 major causes of hyperproteinemia on SPE that are non-pathologic.
Dehydration
Prolonged tourniquet time
Which is normally higher, hydrostatic or oncotic pressure?
Hydrostatic- thus our lymphatic work
What is the result of A-1-antitrypsin disease on the lung? Liver?
Emphasema
Cirrhosis
What proteins go down in nephrosis?

what ones go up?
gamma globulin (Ig gamma) and albumin

Alpha-2 macroglobulin
Nephrosis will predispose to what type of infections, viral or bacterial?
Bacterial due to loss of gamma globulins
What is the effect in increased IgA levels on SPE?
Can cause beta-gamma bridging
What is the effect of lupus on an SPE?
Elevated beta region due to elevated C3 levels (also elevated in hep c)
What causes hyper-IgM syndrome?
Defect in CD40 ligand, B cells can't class switch
---> low IgG than also
What is the function of alpha-1 antitrypsin?
Why does it cause emphysema?
Anti protease

Lung lacks protection from the bodies own enzymes
What are the normal and defective alleles in alpha-1 antitrypsin disease?
M: Normal
Z: Defective
MZ= asymptomatic, a-1-at ~60% of nomral ZZ= severe
What does nephrotic syndrome classically look like on SPE?
A2 increase, Decreased albumin, decreased gamma
What does cirrhosis classically look like on SPE?
Increased beta, gamma or both

Decreased Alb, A1, A2
What does acute inflammation classically look like on SPE?
A1 or A1 and A2 increased, decreased alb

Protein synthesis shifted from albumin to acute phase reactants
What does Chronic inflammation classically look like on SPE?
A1, A2, B, and Gamma increased

Decreased albumin
What does parametric distribution mean?
Distributed in a bell curve/Gaussian distribution
What is coefficient of variation?
CV = SD/mean --> expressed as a percent
What is the equation for standard deviation?
Difference in all values from the mean squared and added together divided by N-1
Square root of that.
What is the advantage of CV vs. SD?
CV is unitless, thus you can compare different assay regardless of units.
What N is generally considered adequate to establish a reference interval?
100-120
What is partitioning?
A reference interval for a specific population. Still need 100-120 people for each of these populations to be acceptable. Eg. TSH in 1st trimester
How do you establish the "abnormal" cutoffs in a non-parametric population?
Take the highest and lowest 2.5% of participants in your study and establish that as the cutoff.
How do you compare 2 populations, taking the same test, to see if the groups are different? eg.
100 people with disease ---> 80+
100 people w/o diesease ---> 10+
Chi-square --> do not have to calculate on boards, just know concept

Result--> P value
Define P value
Probability that the null hypothesis is true. 0.05 = 5% chance that the null hypothesis is true
What is a Fischer test?
When the False positives or false negative groups are < 5. This data would not be eligible to be compared with a chi-square test
What is the difference between a paired vs. unpaired t-test
Paired uses the same subjects for both tests.
Unpaired uses experimental vs. control group.
The same analyte is run on 2 different analyzers; what statistical test is run to determine which is more precise?
F-test
What is sensitivity?
True positives/ disease

likelihood that a test will be positive a a diseased individual
What is specificity
True negatives/No disease

Likelihood that a test will be negative in a healthy population
What is accuracy?

AKA?
AKA efficiency

True positive + True negatives/all results
What is a receiver-operator characteristic curve?
Sen plotted with 1-Sp. The greater the area under the curve, the better the test.
Other than paired-t-test, what is another way to compare two analyzers with the same specimen?
Correlation analysis --> correlation coefficient
What is the difference between standard regression analysis and Deming regression analysis when assessing correlation?
Standard assuming that only the result has variation. Deming regression assumes that error is found in the X and the Y.
What does each contain?
Red top tube, Green, Gray, Purple, Blue?
Red- Serum
Green - Plasma with heparin
Gray- Plasma with k+ oxalate
Purple- EDTA (heme)
Blue- 3.2% Na+ citrate (coag)
What is the difference between trough and peak.
Trough- measure right before administration
Peak- measure shortly after administration (gentimicin)
What is Bias?
proportional bias?
constant bias?
The difference between the result and the "true" concentration.
-Y changes by a % with X (m)
-Y is a fixed amount different than X (b)
What is the difference between a waived and moderate complexity test in the setting of a place that provides both?
Moderate complexity tests require proficiency testing.
What are the Westgard rules?
1 >3SD
2 sequential >2SD
Range of sequential > 4SD
4 sequential > 1SD
10 sequential on one side of mean
What are the 2 phases of aspirin toxicity?
Respiratory alkylosis

Metabolic acidosis
What are the 3 current criteria for identifying type 2 diabetes?
Fasting glucose >126
Random or 2h glucose >200
Hb A1c >6.5
What are the criteria to identify pre-diabetes?
Fasting glucose >100
2h glucose > 140
Hb A1c > 5.7
What HLA markers are associated with type 1 diabetes?
HLA DR3 and DR4

DQB1
What DQ allele is associated with type 1 diabetes?

Protective?
B1- 0201 and B1-0302

B1-0602
Fasting plasma glucose of 110, oral glucose tolerance test or >200.

How is this classified?
Hyperglycemia.

In the absence of DKA, diabetes is only diagnosed if these symptoms are present on two occasions. One is pre
What is the fructosamine assay?
Measure of glycosylated albumin. Better in pregnancy because changes faster so can be measured every few weeks.
How does glomerular disease manifest itself on Urine protein electrophoresis?
Albumin and transferrin (Beta peak) in urine

With increased damage
--> A1 and gamma globulins
How does tubular damage manifest itself on urine protein electrophoresis?
Albumin and A2 x2
If the urine sodium to plasma sodium ratio is greater than the urine creatinine to serum creatinine ratio, what does this mean?
likely acute tubular necrosis
What method is used to measure protein on urine analysis?
Glucose?
Tetrabromphenol blue

Glucose oxidase -- Falsely low with ascorbic acid
What method is used to measure blood on urine analysis?

Ketones?
Peroxidase

Nitroprusside
Ascorbic acid interferes with detection of what 2 measurements on urine analysis?
Glucose (glucose oxidase)

Blood (peroxidase)
What are 2 drugs that cause red urine?
Pyridium and phenolphthalein
What are 3 things that can cause orange colored urine?
Rifampin
bilirubin
pyridinium
What disease causes black urine?
Alkaptonuria -tyrosine and phenylalanine
How is specific gravity calculated?
Weight of urine/ equal volume of water

N= 1.002-1.030
0.2% -- 3% heavier than water
At what glucose level do you start seeing glucosuria?
>150
According to CLIA/CAP, generally how long must documentation of individual tests be storred (QC, reports, proficiency testing)?
2 years
How long must a specimen be saved, according to CAP, after it is analyzed?
24 hours
NADPH is the final product in many chemistry reactions; what is its wavelength?
340 nm

-likely the most important wavelength to know
Does a slight increase in troponin levels have clinical significance in unstable angina or renal disease?
Both can cause elevations of troponins. In both diseases, the elevations are associated with worse outcomes.
Beyond as a marker of acute phase inflammation, what is the value of CRP as a risk factor?
Slight elevations are associated with increase risk for CAD
What is the formula for estimating true calcium levels with a low albumin?
Ca + (4.5 - albumin)*.8 = corrected

(Add 0.8 * grams/dL under 4.5)
What two ions are mainly affected by hyperglycemia?
Causes hyponatremia (1.6 per 100 increased) and Hyperkalemia.
How is fractional excretion of sodium calculated?
FE= (Urinary Na+/ plasma sodium)/ urinary creatinine/plasma creatinine
How can fractional excreation of sodium be used to distinguish prerenal azotemia from acute tubular necrosis?
Prerenal azotemia FE= <1%
ATN FE>2%
What is the value of Fractional excretion of urea vs. FE sodium?
FE urea < 35 is a better test for prerenal azotemia when the patient has been on diuretics
What is the effect of decreased magnesium levels on serum potassium?
Decreased levels due to increased loss in kidney

Calcium is also decreased.