Can't figure out how I am positive for Chlamydia

[BrighterFuture]

My current girlfriend had Chlamydia when I met her, but she didn’t find out until weeks after we were having unprotected sex. We both got treated, but 3 months after treatment, I start having symptoms. I now have Chlamydia and can’t explain how since I haven’t been with another girl and she swears being faithful while I was gone. I was gone for 6 weeks right at the start of our relationship though. I am trying to find a medical explanation before assuming any further. I seek your expertise and experience. Here is the timeline and facts.

May 15th- June 8th= We met and had unprotected sex during those 3 weeks.

June 8th- July 23rd= We were separate. I didn’t have sex with anyone else.

June 25th= I was NEGATIVE for Chlamydia.  Swab and urine test Amplified with target capture. Test was done 40 days since I was first with her and 17 days after last time.

July 9nd = She is POSITIVE for Chlamydia. Treated with 1gr Azithromycin.

July 12th= She is POSITIVE for Chlamydia at STD clinic.

July 14th= I was NEGATIVE. Urine direct immunofluorescence test. Test done 60 days since I was first with her and 36 days after last time. I took 500mg Azithromycin every 12 hrs for 3 days.

July 22th= She tests NEGATIVE . Swab test Genprobe Tigris DTS/Nucleic Acid Amplification.

July 23=  We resume unprotected sex since she was cured and I was never positive. Plus both received treatment.

July 29th= I was NEGATIVE again for the 3rd time.  Test done 51 days after last time I was with her and 75 days after the first time being with her while she had the infection.  Urine test BD Probetec DNA amplified assays.

August 5th= She is NEGATIVE for the second time after being treated.  Same Swab test as on the 22nd. We are happy at this point. Since we are both in the clear, or so I thought.

Sept 28th= I start to have pain urinating and slight discharge. I went to my urologist and tested POSITIVE for Chlamydia urine test DNA, SDA.

Sept 29th= Her test is POSITIVE as well.

Baffled!!

[Edward W Hook, MD]

Glad to help.  Again, I appreicte all that you and your colleagues do.  Take care. EWH

[Vance2335]

Thank you for the answer Dr.Hook. And thank you for all that you do on this site. I learned most of what I know from you and Dr.HHH.

[Edward W Hook, MD]

Hi Vance.  I appreciate all that you do on the Community site.

IN the past the people who read PAP smears tried to identify "changes suggestive of chlamydia infection" (that is how they often wrote their assessments) in PAP smear specimens.  These results were often wrong.  More recently however the companies that make nucleic acid amplification tests for gonorrhea and chlamydia (you know the names, Gen-Probe, Becton-Dickinson, Roche, Abbott, etc) have evaluated the performance of their tests in PAP smear transport medium and found that they do work well in this sort of specimen.  These tests are just as sensitive as a genital swab specimen or a urine test using these tests and are to be believed.  Their false positive rates is just as low for this sort of test as for specimens from other sites.  

So when one partner has infection detected from a PAP smear specimen, as long as they know it was tested with a proper test, and the other does not we have to work through the possibilities (i.e. other partner, antibiotics, etc) and, sometimes, scratch our heads.  There are very few false positives however, just as with genital tests.  EWH

[Vance2335]

Hello Dr I am wondering if you can make a quick comment on my question. I am a Co-CL in STD and chlamydia and I have been seeing a high number of questions in the chlamydia forum where a woman has done a pap and had a positive test for chlamydia. The partner will then test and is negative. So I am wondering have you noticed this? Is this the test that can give a higher rate of false positives?

Just want to try to give these people the best information and the cheating partner seems to be less and less likely just based on the same type of question I am seeing from many different people.

[Edward W Hook, MD]

I hope that my comments have helped you.  You now know clearly what the recommended therapy is for chalmydial infection and some of the factors which could contribute to the confusion and stress that you and your GF have had.  It she was treated with only 500 mg of azithromycin, as you know from my post, she was treated with less that the recommended dose. This sould be a contributor to the problem.  If this was the case, the docotos also owe you an explanation, not to mention an apology. EWH

[BrighterFuture]

The problem is that all the doctor's involved seem to have basic knowledge about STDs and they offer contradicting opinions for our situation. I include my Urologist and her GYN, the hospital, planned parenthood, etc..
I thought I could find a better answer here since you guys deal with these scenarios more often than other docs.

[Edward W Hook, MD]

500 mg of azithromycin is less than the recommended dose for chlamydia treatment.  Too low a dose could suppress the infection and make it difficult to detect but not cure it.  I cannot comment on whether this particular therapy might explain what has happened here.  My advice would be to talk with the docotors involved.  EWH

[BrighterFuture]

Hello Dr.Hook

I am writing back to give you a piece of information that you might find alerting as a practicing doctor since, to me, it seems like medical negligence on part of the hospital. I'd love to know your thoughts.

We ordered the medical records for the day my girl friend received her treatment (at the most prestigious hospital in NYC). It happens that they gave her 2x250mg pills of Azithromicin instead of 1gr. She did not receive any other treatment.

1) Could this be the explanation of why the bacteria was not completely eliminated, remained undetectable and then came back?

2) With this new piece of information, would you change your opinion about it being unlikely for two successive tests, taken as far out as 26 days after a 500mg treatment to be negative before they again became positive?  
Considering that both tests were cervical swabs. Is it possible for the both tests to be negative due to the bacteria not being in her cervix at the time of the swabs, but living maybe in her fallopian tubes or elsewhere from were the bacteria recurred later?

3) We are very upset that the hospital didn't give her the proper treatment. Or is it 500mg enough to kill this disease? It looks to me more like a mistake on their part, what are your thoughts on this? I am sure you might be disappointed at them.

Thanks for your time Dr Hook

God Bless

[Edward W Hook, MD]

Sorry, the scenario your outline does not make biological sense.  

Sorry , can't process the second scenario.  You are devolving into the "what if"s and "has it ever" type questions.  They are simply not answerable with confidence.  

EWH

[BrighterFuture]

Thanks again for your reply and if you just bare with me for one more thought before I go pointing fingers.

I wanted to exhaust the possibility that I could have given it back to her after she was cured. I last saw her on June 8th. I was negative on June 25, negative also on July 14th, treated with Azithromycin just in case, then give it back to her on the 23rd, then I'm negative again on July 29th. Is this possible?  

Also, If she contracted it again it must have been between July 9th that she got treated and the 23rd of July that I came back. So between those 14 days. I know that Azithromicin stays in the blood for a few days, would it be possible to contract the bacteria again in those 14 days with Azithromicin in her blood? If so, when is more likely that it happened and how can she be negative on August 5th?

Thanks for your patience.

[Edward W Hook, MD]

I saw the dates.  They help but, for better or worse, little with regard to humans and infectious diseases is definitive.  I do however agree with your statement about false positves being unlikely, given the use of two differentt tests.

As you also point out, it your partner's azithromycin therapy had not worked it would be unlikely for two successive tests, taken as far out as 26 days to be negative before they again became positive.  

Thus, as I said, that leaves reacquisition as the most likely cause of her (and your) repeated   infections.  EWH

[BrighterFuture]

Thank you doctor for your reply.

Please don't be afraid of insinuations as I am trying to find the logical answer to this based on the facts and your knowledge.

The possibility of a false positive on her is not feasible to me since she got 2 different tests to confirm the positive at two different clinics, plus she had bleeding and pelvic pain as symptoms, which cleared up after one week following the 1gr of Azithromycin.

If the treatment with Azithromycin didn't work on her, what are the chances that 2 post treatment tests give a Negative result? If one test done too soon was negative I could believe it, but she had one test 13 days after taking the antibiotic and then another test 26 days after taking it, and BOTH tests were NEGATIVE. If the infection was not completely eliminated, wouldn't the bacteria have shown up at least on the second test at 26 days? How can it possible in this case for the chlamydia to linger undetectable to DNA swabs, I am not too fond of this theory. Are you, based on these facts?


If you could, please take another look at the dates and how the tests and treatment for us occurred. Please help me narrow it down to what it is more likely that happened. It can't be such a mystery.

[Edward W Hook, MD]

Welcome to our Forum.  I'll try to help.  There are, VERY rarely, false positive tests for chlamydia and treatment failures can occur but both are, as I said, rare.  Statistically the most likely result is that chlamydia was re-introduced into the relationship following treatment.  I do not mean to cast doubt on your relationship but statistically this is the most likely source of the recurrent infection.  Let's now discuss some of the other, less common possibilities.

False positive tests. These do occur rarely but are not a concern in your situation since false positive tests are not transmissible and you acquired a positive test. When false positive tests occur they tend to falsely positive on only one type of test (i.e the SDA or gen-Probe tests are different tests)

Slow clearance following infection.  Modern tests are so very sensitive that they can continue to detect chlamydial infection after successful treatment, detecting traces of dead organisms.  This effect occurs gradually over time and by 3 weeks clearance is complete.  Positive tests for the first two weeks following treatment however can be due to this effect.  Given the time interval you mention this seems unlikely.  

Treatment failure.  There are documented reports of failure of azithromycin treatment for chlamydia.  Research studies show that these occur in less than 3% of cases.  Thus treatment could suppress the infection but not eliminate it, causing it to then recur. In these situations, the chlamydia often but not always remains detectable despite the apparent response to therapy.  

Those are the possibilities.  Sorting them out is difficult and perhaps impossible.  Perhaps my comments have been helpful however.  EWH