General-1 Flashcards
What is the function of Cystatin C?
Measure GFR
SPEP with decreased Albumin spike and increased Alpha-2 Macroglobulins. What condition is associated with this finding?
Nephrotic syndrome
Patient with low serum cholinesterase level, what is the next step?
Test if the cholinesterase can be inhibited by dibucaine.
-Patients w/ hereditary hyporcholinesterasemia (homozygotes) have low levels of cholinesterase that is not inhibited by dibucaine, whereas normal cholinesterase is inhibited
Alcoholics have what lab findings? (6)
- Hypophosphatemia
- Hypomagnesemia
- AST>ALT
- Increased GGT
- Elevated bilirubin
- Increased MCV
What vitamin toxicity can cause Pseudotumor Cerebri?
Vit. A
What is the best test to evaluate FUNCTIONAL liver status?
PT/INR
Patient with positive ANA, what drug are they likely receiving?
- Procainamide
- Hydralazine
*Procainamide carries a 15% to 20% risk and Hydralazine carries a 7% to 13% risk
What lipid tests require the patient to be fasting?
- Triglycerides
- calculated LDL
*Friedwald Calculation
Where is DHEA-S produced?
Adrenals
What instrumentation measures the amount of light deflected at an angle?
Nephelometry
-Measures amount of light that is deflected at NON-90 degree angle by particles in solution
*Flourometry uses 90 degree to capture only emitted light and not transmitted light
What percentage of plasma volume is water?
93%
*Depends on hydration level
T/F: Fructosuria is a benign condition.
True
Patient with WBC = 230,000 with elevated serial potassium levels. What is the cause?
Spurious increase in Potassium related to blast crisis
An elevated BUN to Creatinine ratio is seen in what conditions?
Volume depletion/Decreased renal blood flow
-CHF, Shock, Urinary obstruction, etc
- Urea clearance decreases more than creatinine clearance
- Normal Urea Nitrogen:Plasma Creatine 10:1
- Volume depletion >20:1
Patient has creatinine measured via 2 methods. One methods gives a normal result, whereas the sample with alkaline picrate (Jaffe reaction) resulted in Elevated Creatinine. What is the reason?
Patient has elevated Acetoacetate
-Ketone bodies cause positive interference in Jaffe reaction
Patient has Increased Osmolar Gap but Normal Anion Gap. What was ingested?
Isopropanol
Calculation for Osmolar Gap.
- CO = 2 x NA + 1.15 * GLU/18 + BUN/2.8
2. OG = MO - CO
Calculation for Anion Gap.
AG = NA - CL - HCO3
Patient with increased osmolar gap and increased anion gap. Testing for methanol was negative. What did they ingest?
Ethylene glycol
Calculate LDL cholesterol:
- Total cholesterol = 260
- HDL = 40
- Triglycerides = 200
Friedwald Equation:
LDL = Total - HDL - (triglycerides*/5)
LDL = 260 - 40 - (40)
LDL = 180
*Not valid if triglycerides >400
Test tube with creamy layer on top and opaque plasma below.
Increase in Exogenous and Endogenous lipids
- Exogenous (chylomicrons-creamy layer)
- Endogenous (VLDL-opaque layer)
*Increased cholesterol does NOT make plasma cloudy
What is the initial screen for someone suspected of having Acromegaly?
Serum IGF-1
What inhibits prolactin secretion?
Dopamine
Methylmalonic acid is elevated in what?
Vit. B12 deficiency
AST vs. ALT:
-Which is found in mitochondria?
AST
Diagnosis: Elevated Alk Phos, slightly elevated Bilirubin and recent onset painless jaundice.
Pancreatic Cancer
What is CA 19-9 a marker for?
Pancreatic cancer
Maternal Quad screen - Down Syndrome findings
- hCG (Elevated)
- Inhibit (Elevated)
- AFP (Decreased)
- Estriol (Decreased)
What is the active metabolite of Cocaine?
Benzoyl Ecgonine
