took chlamydia test incorrectly twice... false negatives?

[talktal]

about 3 weeks ago i had unprotected sex with a girl i had just met.  then about two weeks after, i had a general uncomfortable feeling after urinating.  a slightly burning sensation, but very mild, and a continuous uncomfortable feeling on the tip of my penis which kept me up at night.  i had no discharge, and maybe a slight burning sensation when urinating at times, but this is generally what i feel if my bladder is completely full and my stream is strong.  well, i was panicked and i went online and ordered a full panel std test through a website which included a urine test for chlamydia.  i went to the lab it told me to, and saw a sign on the toilet saying i should wet wipe my genital and only use mid stream urine in the sample, so i did that.  then, three days later after the uncomfortable feeling did not subside i went to my general practitioner and he gave me another urine test, as well as prescribed some antibiotics, but he thought i had more of a prostate issue.  well, when i went to take the urine test he gave me, i did the exact same thing i did at the other lab and wet wiped the tip of my penis and collected a mid stream sample.  both tests came out negative.  since i took the test incorrectly could they both be a false negative?  i just read how youre not supposed to clean the area and collect first stream, not mid stream for chlamydia.
there was also a culture test submitted to check for any possible bacteria in the urine.  it tested negative as well.

[Edward W Hook, MD]

Thanks for the clarification. the doxycycline you took is recommended therapy both for NGU and for chlamydia.  At this time, following the resolution of your symptoms there is, unfortunately, no good way to determine for sure whether chlamydia or something else might have caused your symptoms.  Thus the good news is that you are better and the bad news is you won't know what was treated.

If you are asymptomatic at this time there is no need or recommendation for follow-up testing.  EWH

[talktal]

thank you for your reply, dr hook.  i was prescribed 10 days of doxycycline , 2 doses a day 12 hour apart.  after the third day my symptoms subsided.  i still would like to know if i contracted an std or not, but i assume its too late to know for sure now.

[Edward W Hook, MD]

Welcome to the Forum. I'll try to help you sort things out.  You are correct, you did take the test incorrectly.  Despite that , my guess is that your test results are correct.,  Tests for STIs such as chlamydia should be collected using urine collected just as you begin to urinate, not with a mid-stream specimen which is the right way to test for urinary tract infections.  Despite that, most urine specimens among persons with chlamydia, even when collected as mid-stream specimens tend to be accurate.  Some studies even show no significant difference between specimens collected at the beginning of urination and mid-stream specimens.  You may have non-gonococcal urethritis (NGU), of which only 30-40% is caused by chlamydia.

NGU is typically diagnosed based on signs of inflammation, manifest as buring on urination or a penile discharge and the presence of increased numbers of white blood cells in urine or a swab specimen.   Much NGU is caused by bacteria of which the association with chlamydia is most certain.  Other individual micro organisms cause it less often (trichamonas, some ureaplasmas, Mycoplasma genitalium, oral bacteria  introduced into the urethra during receipt of oral sex, etc.) but are not typically tested for and despite optimal microbiological evaluation, in about 30% or more of cases there is no clear cause.  We also DO know that there are non-STD causes of urethritis (NGU) as well.  In most men NGU responds well to recommended treatment with doxycycline or azithromycin irrespective of cause.  

What is going on my be irrelevant, depending on what medication has been prescribed for you and how you responded to it.  What medication did you receive?

More to follow after I hear what medication you were prescribed, how long you took it, and your response to therapy.  EWH