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STD tests - worried I might have 'false' negative results

Hi Doctors

Had some tests done a few weeks ago.  Here are some of my results:-

Chlamydia Trachomatis DNA(PCR) Not detected
N. Gonorrhoeae DNA (PCR) Not detected
Mycoplasma Genitalium DNA(PCR) Not detected
Ureaplasma DNA (PCR) Not detected
Trichomonas Vaginalis DNA(PCR) Not detected
Gardnerella Vaginalis DNA(PCR) Not detected
Herpes Simplex Type I/II DNA Not detected

Mycoplasma/Ureaplasma Culture  :-                                            
Negative See Additional

+++ mixed skin flora
NO N.gonorrhoeae or Candida species isolated.

Sample type See Additional
NO Trichomonas vaginalis seen..

The doctor asked me if I had urinated 3 hours before.  I think it was around 3 hours between the last time I urinated and the time I took the test - but I can't remember now - might have been a hour or even less.  Just worried that, if it had been an hour or less between the time I last went to the toilet last and when I took my urine test for STDs, I might have 'fooled' the tests, and may have a 'false' negative, when I might actually be positive for some of these infections.  Just wanted to know if it makes a difference how long you wait between urinating last, and urinating for an STD test, and whether, in my case it affects the accuracy of my test results.  Note - the doctor did not take a swab - just took a urine sample.

1 Responses
1024580 tn?1331574121
Thank you for your post.
For a PCR test result from urine to be reliable, the urine needs to remain in the bladder for at least two hours before the sample is taken.  Otherwise one would need to do a PCR swab instead.  If you are unsure, it might be worth repeating this test, making sure that you fulfil this requirement.
The other test that you had was a genital swab for microscopy and culture, and this was negative for all infections.  All it showed is normal bacteria from the skin. This does not need repeating.
Mycoplasma genitalium is the only one relevant from the point of view of STDs.  The other varieties are not tested in the context of STD screening.
Best wishes,
Dr José
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