24 hr urine test (pregnancy, blood, advantage, doctor)

[Ritzui]

What does a 24 urine test show in the results that a small cup sample of urine doesn't? Does it matter if my 24 urine test has sperm in it? I just woke up and I guess I had an erection and when I pee I saw sperm coming out.

[Medical Lab Guy]

Originally Posted by Ritzui

What does a 24 urine test show in the results that a small cup sample of urine doesn't? Does it matter if my 24 urine test has sperm in it? I just woke up and I guess I had an erection and when I pee I saw sperm coming out.

The 24 hour collection vs the spot urine test.

One can get away with doing a spot urine when there is a constant concentration of what is being measured being secreted into the urine. All we do to equalize the hydration status variances in water content is tie it to creatinine which is a constant. The results are reported in terms of a ratio such as the protein/creatinine ratio.
It is more accurate at times and less cumbersome than collecting a 24 hour urine where people sometimes fail to collect the entire collection. Also easier to collect and preserve the sample.

The disadvantage of a spot urine is that not all substances are secreted into the urine at a constant rate and sometimes they occur in spurts throughout a 24 hour period. One can miss such a spurt with one single collection of urine. The other disadvantage is that some reference ranges for analytes are included in the definition of symptoms. The definition of nephrotic syndrome "Nephrotic-range proteinuria is the loss of 3 grams or more per day of protein into the urine or, on a single spot urine collection, the presence of 2 g of protein per gram of urine creatinine." "During pregnancy, due to the increased renal blood flow, some additional protein may be lost in the urine. This increased protein loss should not normally be in quantities exceeding 300 mg in 24 hours. If more than 300 mg in 24 hours is found, this may signal the development of pre-eclampsia."

We aren't concerned about sperm in urine in a 24 hour collection. The sperm contamination of urine can increase the protein content on a urinalysis which is done on a spot urine. It is typical to get a trace amount of protein in such contaminated specimens. Just a side note that we were obligated for medical-legal purposes if sperm was seen on a urinalysis on a female minor to document a call to the ordering doctor.
The amount contaminated with sperm will not alter the overall concentration of the 24 hour collection which should be in the liter volume range.

[Ritzui]

Originally Posted by Medical Lab Guy

The 24 hour collection vs the spot urine test.

One can get away with doing a spot urine when there is a constant concentration of what is being measured being secreted into the urine. All we do to equalize the hydration status variances in water content is tie it to creatinine which is a constant. The results are reported in terms of a ratio such as the protein/creatinine ratio.
It is more accurate at times and less cumbersome than collecting a 24 hour urine where people sometimes fail to collect the entire collection. Also easier to collect and preserve the sample.

The disadvantage of a spot urine is that not all substances are secreted into the urine at a constant rate and sometimes they occur in spurts throughout a 24 hour period. One can miss such a spurt with one single collection of urine. The other disadvantage is that some reference ranges for analytes are included in the definition of symptoms. The definition of nephrotic syndrome "Nephrotic-range proteinuria is the loss of 3 grams or more per day of protein into the urine or, on a single spot urine collection, the presence of 2 g of protein per gram of urine creatinine." "During pregnancy, due to the increased renal blood flow, some additional protein may be lost in the urine. This increased protein loss should not normally be in quantities exceeding 300 mg in 24 hours. If more than 300 mg in 24 hours is found, this may signal the development of pre-eclampsia."

We aren't concerned about sperm in urine in a 24 hour collection. The sperm contamination of urine can increase the protein content on a urinalysis which is done on a spot urine. It is typical to get a trace amount of protein in such contaminated specimens. Just a side note that we were obligated for medical-legal purposes if sperm was seen on a urinalysis on a female minor to document a call to the ordering doctor.
The amount contaminated with sperm will not alter the overall concentration of the 24 hour collection which should be in the liter volume range.

what happens if I get body wash in the container?

[Medical Lab Guy]

Originally Posted by Ritzui

what happens if I get body wash in the container?

Impossible to say or predict as one isn't going to experiment by doing two tests one with body wash and the other without. Not going to happen. It may have no impact or significant impact depending on what is being tested for.

Any adulterants present may interfere depending on the test ordered by either adding constituents being measured coming from the body wash or interference with the chemical reactions inhibiting specific reactions or promoting non-specific reactions. It may also have no effect at all.

The preservatives used in 24 hour containers are usually concentrated acids or bases so you don't want to come in contact with it because it will burn your you know what. It preserves the chemicals in a specific chemical state or it is used to maintain solubility rather than insoluble chemicals that promote crystal formation that would alter the even distribution of the chemicals throughout the sample. The preservatives don't protect agains adulterants.

There is no test for adulterants in the urine with exceptions with some substance abuse specimens of people trying to cheat.

You can mention it to your doctor when you go over the results and let him scratch his head over it. Hopefully the 24 urine test is one piece that would be consistent with his diagnosis if any related to the test. All test are interpreted within the clinical context. When that is done false negatives and false positives are kept to a minimum.