storage and handling

Question 1

what effect does cooling urine from fridge to room temperature have?

Answer 1

will falsely increase crystals that wont precipitate out when urine warms

Question 2

formalin dose?

Answer 2

student lab: 6%: 1-4 drops/5mL of urine

anatomy lab: 37%: 1-4 drops/30mL

Question 3

sodium fluoride dose

Answer 3

1% 1-4 drops/5mL urine
2% 1-4 drops/30mL urine

Question 4

what should urine be protected from?

Answer 4

heat (room temp) and light (can cause the deterioration of some urine constituents)

Question 5

what does formalin and sodium floride alter?

Answer 5

• the glucose, blood, and leukocyte test on a dip stick

Question 6

when does the urine sample begin to deteriorate?

Answer 6

imediately

Question 7

what changes can occur to urine if left at room temperature (9)

Answer 7

1. bacterial proliferation
2. decreased glucose (if present as bacteria will metabolize it)
3. if urine is alkaline it will cause lysis of RBC and deterioration of cast
4. sediment changes
5. bilirubin will disappear due to hydrolysis (room temp) or oxidation (light exposure)
6. urobilinogen will disappear due to light exposure
7. pH may change
8. The sample may evaporate, increasing the specific gravity
9. chemicals may precipitate and be misinterpreted as crystals