concern about a false negative on gon and clam test

[ndsomadvice]

doc i had a urine test done for gon and clam form quest diagnostics i think it was a amplified ct/gc pcr test.the test was negative but i urinated like a half hour before the test.the doctor never asked me how long its been.i was concerned it could be false because i read u should wait 2 hours before test to urinate.so when i had some clear discharge in the morning after i peed i went straight to the clinic where they did a swab test which was sent to the same place.when i had it done the lab was closed so i held on to the sample for 48 hours before i dropped it off.i then read that u should refrigerate it if its more then 24 hours.the 2nd test was negative also but i am concerned that it might be a false negative because it was 48 hours not in a refrigerater.

1-should i be concerned at all about a false negative?

[H. Hunter Handsfield, M.D.]

If I had recognized your username, I would deleted your question without responding.

The way to address symptoms is through a personal health care provider.  I have no further comments of advice.  Note MedHelp rules sets a maximum of 2 questions in any 6 month period.

[ndsomadvice]

i wrote to you on 9-22 about the situation.i just got tested to be sure. my ex and my new gf have no symptoms.the discharge only happens once in awhile after peeing.never can milk anything out during the day or in the morning when i wake up.all urine tests were negative for wbc.no burning or pain.

been with new gf for 7 months theres no chance that we can be giving it back to eachother with no symptoms is there?

[H. Hunter Handsfield, M.D.]

Urinating prior to testing probably makes no difference.  In the research that established the performance of the marketed tests, people who had urinated within 2 hours were not studied.  Therefore, FDA regulations require that stipulation in the formal advice about how to use the test.  In other words, it doesn't mean the test is invalid if less than 2 hours have passed since urinating, only that it isn't known for sure.  Several laboratories have done their own in-house studies and found no difference, even when someone had urinated just a few minutes before testing.  Most STD clinics and other agencies do not stress the time interval when doing routine testing--which is why the doctor didn't ask you.

Similarly, waiting 48 hours probably makes no difference either.  Refrigeration would have been better, but even without it, most likely the result was accurate.  One of the main reasons the amplified DNA tests are such an important development is exactly that:  they can be used for screening even in settings like tropical Africa, where refigeration isn't available and it might take a few days for the specimen to get to the laboratory.

What should you do now?  If your scant morning discharge is completely clear, it might not be abnormal.  Or you might have nongonococcal urethritis (NGU).  In that case, or if you have had sex with someone known to be infected with chlamydia or gonorrhea, you should have been treated (or should be treated now) with antibiotics, regardless of the negative test result.  However, if you were tested simply for screening, i.e. because of general concern about risk, nothing more need be done.  But if in doubt, or if you believe your morning discharge might be abnormal, return to the clinic for personal examination and perhaps retesting if the provider recommends it.

Good luck--  HHH, MD