Long-term Eradication of Chlamydia trachomatis Genital Infection After Antimicrobial Therapy

Abstract

<h3>Objective.</h3> —To determine whether<i>Chlamydia trachomatis</i>urogenital infections persist or relapse after antimicrobial therapy by serial measurement of chlamydial-specific DNA using the polymerase chain reaction (PCR), cell cultures, and serological studies. <h3>Design.</h3> —Prospective evaluation of an inception cohort. <h3>Setting.</h3> —University student health clinic. <h3>Participants.</h3> —Twenty women with culture-proven and PCR-proven<i>C trachomatis</i>urogenital infections. <h3>Measurements.</h3> —Incidence of persistent infection as determined by PCR, culture, and serial measurement of local and systemic antibody to<i>C trachomatis</i>for 5 months after doxycycline therapy. <h3>Results.</h3> —Prior to therapy,<i>C trachomatis</i>was isolated in cell culture from the cervix in 19 of 20 women, from the urethra in 13 women, and from the rectum in 13 women. All culture-positive specimens were also PCR-positive. Immediately after completion of antimicrobial therapy, all women had negative cell cultures for chlamydia. Ten of 20 culture-negative cervical specimens and two culture-negative urethral specimens had chlamydial DNA present immediately after treatment. In addition, three women had detectable DNA from cervical specimens 1 week after treatment. The presence of cervicitis (<i>P</i>=.01), high inclusion counts (<i>P</i>=.004), and serological evidence of recent infection (<i>P</i>=.0004) were each significantly associated with PCR positivity after treatment. All 384 subsequent cervical, rectal, and urethral specimens collected over 5 months were negative by both PCR and culture with the exception of one woman who was reinfected. Serum immunoglobulin M (IgM) titers, geometric mean serum immunoglobulin G (IgG) titers, and prevalence of local antibody to chlamydia progressively declined after treatment. <h3>Conclusions.</h3> —Standard antimicrobial therapy is effective in the long-term microbiologic eradication of uncomplicated<i>C trachomatis</i>urogenital infections. The presence of chlamydial DNA after antimicrobial therapy is of short duration and reflects excretion of nonviable organisms rather than persistent infection. (<i>JAMA</i>. 1993;270:2071-2075)