Wondering how

Dr., last week I had all the symptoms of Chlamydia but didn't know what I had until my Dr. visit.  He prescribed me Zithromax on the spot, a urine sample was taken & confirmed today I have Chlamydia.  I have been with my girlfriend 4yrs & have never been with anyone else, period.  I have been tested for all STD's in 2005 (due to divorce) & nothing.  I have read all sorts of information & posts but nothing answers my biggest question:

1) Is it possible my girlfriend got chlamydia prior to us getting together 4yrs ago, never know it & out of the blue I get it?  We have sex 3-4 times a week so I find it very strange that if she has had it all this time that my lottery ticket was called.  

2)She said she has no symptoms & is going to be tested next week after her period.  She is currently taking a very heavy dose of Amoxycillin for the past 5 days for what her Dr. said could be Bronchitis.  Will Amoxycillin rid of chlamydia so her test possibly will come back negative, thus leaving me clueless?

Thank you ever so much!

[Edward W Hook, MD]

Your circumstance is unusual and hard to explain.  Chlamydia can certainly persist for long periods without symptoms (even up to four years).  Transmission certainly does not occur with every exposure but, as you point out, 3 times a week for 4 years is over 200 exposures  - you would have expected it to have happened before now.

Amoxycillin is not good therapy for chlamydia but it certainly can cure some cases and make tests negative.

Finally, are you sure your doctor tested you for chlamydia and not for non-gonococcal urethritis?  What sort of test was it-- some of them do yield false positive test results and (very rarely,) laboratories can make mistakes by swithching specimens.  Hope this is some help.  Feel free to reply with additional questions.  EWH

[H. Hunter Handsfield, M.D.]

Normally Dr. Hook and I don't both respond.  However, I failed to notice that he had already started to reply when I wrote my own response.  As you will see, we agree.  Anyway, you get two for the price of one. Here is what I wrote before I saw that Dr. Hook had replied:

Chlamydia can be carried for a long time, but the longest proved period of chlamydia carriage is 4 years in a single case.  So it is possible your partner has been infected all those years and you only recently caught it from her, but more likely your partner was infected more recently.  That's probably not what you wanted to hear, but in most cases like yours, one or the other partner has had sex with someone else within the past few weeks of months.  That doesn't prove anything, but you need to have a heart-to-heart (but sensitive) discussion with your partner.

Amoxicillin isn't the drug of choice against chlamydia, but it often is effective.  Her test probably will be negative, but that won't prove she wasn't infected, as you fear.  But it really doesn't matter:  she has to be infected.  If you haven't had other partners, she is the only possible source of your infection.

The only other thought is that there is a slight chance your chlamydia test was false positive.  But that's rare with current test methods.

I hope this helps.  Best wishes---  HHH, MD