Flashcards in Chemical Analysis Deck (62):
What is the result on urine of high protein intake?
more phosphates and sulfates are produced
What is the normal pH of a vegetarian diet?
What are some factors that result in persistent urine acidity?
dehydration, illness (diarrhea/fever), gout, diabetes ketoacidosis, gout, pulmonary emphysema, metabolic acidosis
What are some factors that result in persistent urine alkalinity?
renal failure, UTIs, bacterial contamination, alkaline drugs and diuretics
What are 4 methods of proteinuria? OGTS
Overflow - too much in system
Glomerular - too much coming through glomerulus
Tubular - inability to resorb
Secreted - inappropriate secretion into convoluted tubules
What is the strip primarily identifying in urine protein detection?
Does a negative protein test rule out all proteins?
What 5 things can create a false positive protein test?
- Highly buffered alkaline urine
- old/exposed sample
- contaminated container
- some skin cleaners
- blood in urine
What 2 things may cause a false negative protein test?
- diluted urine
- other elevated proteins (other than albumen)
What are some things that can cause transient proteinuria?
- stressors (physical/emotional)
- exposure heat/cold (fever)
3 diseases that cause PERSISTENT proteinuria GPM
- malignant hypertenstion
What percentage of glucose is normally reabsorbed?
what is the threshold where glucose will start entering urine? what condition?
What sugars can give a positive on the dipstick?
What drug can cause a false positive for glucose in urine? what condition?
What are three things that can cause a false positive glucose test?
- some cleaning agents
- drugs (levodopa)
- high [ketone] in urine
What are 4 things that can cause a false negative glucose test?
- cool urine
- high specific gravity
- alkaline urine (bacterial contamination)
- Vitamin C (ascorbic acid) in high doses
What is it called when someone has elevated glucose shortly after eating sweet food
What three things does glucosuria depend on?
- ++ blood glu levels
- -- glomerular filtration rate
- -- tubular reabsorption
What 6 general things can contribute to persistent glucosuria?
- CNS issues
- kidney issues
- endocrine issues
- liver issues
what is a pheochromocytoma?
benign medullary tumor of the adrenal gland
what does the clinitest test for?
glucose and OTHER reducing sugars
What is clinitest most often used to assess?
how well diabetes is being managed
What 4 things can give a false positive clinitest?
- Vit C
- cephalosporins (-cillins)
- drugs for gout and hyperuricemia
- urinary preservatives
What can give a false negative clinitest?
What does the Benedict's test test for? FGMGL
reducing sugars - fructose, glucose, maltose, galactose, lactose
What two conditions are commonly assessed by a urine reducing sugar test?
galactosemia and diabetes, genetic carbohydrate metabolism disorders
How are ketones produced? Where?
liver as part of fatty acid metabolism
Normally, how many ketones are detectable in the urine
Why would ketones be in the urine?
if the body doesn't have enough glucose it switches to the fatty acid metabolism process, releasing ketones
What 3 ketone bodies most commonly appear in urine when fats are burned for energy?
- acetoacetic acid
- beta-hydroxybutyric acid (most)
what is the most common ketone that strips test for?
What can contribute to a false positive ketone test or atypical color?
- combo high specific gravity and low pH
- some meds
- ascorbic acid
what can cause a false negative ketone test?
- old urine
- loss of regent reactivity
What diabetes will have positive ketone bodies?
What diabetes will have negative ketone bodies?
What 3 conditions are indicated by positive blood/hemaglobin in urine?
what is hematuria?
presence of blood or intact RBC's in urine
what is a cause of RBC lysis which will release hemoglobin into the urine?
highly alkaline or very low specific gravity (1.007) urine
How long does transient hematuria last?
What two situations can cause transient hematuria
- strenuous exercise
- menstrual contamination
what 6conditions can cause persistent hematuria
- renal diseases (all parts and incl trauma)
- urolithiasis (kidney stones)
- urinary tract tumor
- prostatic cancer
- virus infection (ebola)
can incompatible blood transfusions result in intravascular hemolysis?
what sort of hypersensitivity reaction is hemolytic anemia?
hypersensitivity reaction type 2
how much conjugated bilirubin is usually present in healthy subjects?
what two conditions can an elevated level of conjugated serum bilirubin imply?
- liver disease
- cholestatic/bile duct diseases
what is unconjugated bilirubin tightly bound to?
is unconjugated bilirubin found in urine?
No, glomerulus filters it out
what is the confirmation of bilirubin presense in urine?
What 4 things can cause a false positive urobilinogen test?
What 3 things can cause a false negative urobilinogen test?
- old urine, exposed to light
- broad spectrum antibiotics
At what time are peak levels of urobilinogen?
what 3 conditions can give elevated levels of urobilinogen?
- liver disease
- intestinal obstruction
- hemolytic anemia
what can the nitrite test indicate early on?
significant and asymptomatic bacteriuria
what do mahy bacteria convert (and to what) that could indicate UTI?
nitrates to nitrites
To detect bacteriuria, which urine sample is the one to choose? Why?
first morning urine, because it must incubate in bladder at least 4 hours
false positive nitrite test?
too much air exposure after collection
false negative nitrite test? 6
- wrong pathogens
- <4 hours in bladder
- low or no nitrate diet
- high specific gravity
- high level of urobilinogen
- vit C
What is the only thing the nitrate test is used to identify?
Why might leukocytes be in urine?
it's normal, could be elevated with UTI
False positive for leukocytes (3)
- Trichomonas infection
- vaginal discharge contamination
- formalin used as preservative