Flashcards in Basic Laboratory Testing Deck (116)
in what sex is creatinine more elevated?
its related to muscle mass, so young men or people with high meat diets. As people age so does muscle mass, creatinine is relatively stable in life.
what is BUN
by-product from the breakdown of protein. the serum [ ] is directly proportional to its rate of production minues the rate of renal removal.
when is BUN low?
with low protein diets, or sever liver disease
what is cystatin C?
low molecular weight protein present in nucleated cells, - its testing is very expensive, and therefore usually used as a reflex for samples with high serum creatinine values.
what is GFR measuring?
the volume of blood that the kidney filters per minute. is usually estimate in our calculations, the lower the value the worst the disease. It can also be calculated using cystatin C.
when does albumin decrease? when does albumin increase?
decrease: starvation and cirrhosis.
what is bilirubin?
the breakdown product of the heme in hemoglobin. Heme is converted to bilirubin in the liver
what is a concern with ^ bilirubin?
d/t liver disease or obstruction. If its isolated finding usually d/t genetic defect.
what is globulin?
the fraction of blood that includes the immunoglobulines, or antibodies. high levels indicate acute or chronic infection, myeloma or recently cleared infection.
how is globulin calculated?
subtracting the albumin from the total protein.
what is myeloma?
cancer of the plasma cells. identified by the antibodies monoclonal and polyclonal.
what is uric acid?
metabolite product from the oxidation of purine bases. high values associated with renal disease, hypertension, gout and use of thiazide diuretics.
what is included in a CBC "differential"?
red cell count, white cell count (lymphocytes, macrophages, and granulocytes), platelet count, hematocrit, and hemoglobin in g/dL.
why is it important for the uw to note the absolute count on a differential ?
relative number of cells present can be normal, white the absolute count is abnormal. This occurs in anemia and hematological cancers.
What is PSA? when are its levels increase?
a protein produced by the prostate. Increased in BPH, and in inflammation (prostatitis).
what are the two forms of PSA in serum?
free and bound. the total SPA is the sum of the two.
What is carcinoembryonic antigen (CEA) ?
is produced by many solid tumors.
when would you run a CEA test?
after cancer tx, if their dx was associated with CEA elevations.
why do we not use CEA typically in insurance screening?
high number of false positives, and if its very high, no cure of any tumor found is generally possible.
what is BRCA?
chest x-ray marker associated with increased risk of development of breast and ovarian cancer.
what is Ca-19-9?
marker for gastrointestinal cancer
what is alpha fetoprotein (AFP)?
marker for liver and germ cell cancer
what is beta chorionic gonadotropin (HCG)?
marker for germ cell cancer
what is a benefit of genetic testing?
clinically determine course of tx and the probability of outcomes for various cancers. None is used in u/w currently.
why is there no set/ standard expected or reference range values?
1. individual insurance companies have different cut offs.
2. individual labratory normal ranges vary.