Effect of Chlamydia trachomatis coinfection on HIV shedding in genital tract secretions

The relations between HIV infection and other sexually transmitted diseases (STDs) are complex.(1) Some studies show that other STDs may enhance HIV i nfectiousness in men and women by increasing viral shedding in genital trac t secretions. In their review, Rotchford et al.(2) combined data from four studies and concluded that HIV was not detected significantly more frequent ly in the genital secretions of HIV-infected persons with Chlamydia trachom atis infection than in the secretions of those without HIV. This report see ks to underscore and expand on the authors' caveats, including problems in choosing appropriate comparison groups, gender of the participants, and met hods for detecting chlamydia and HIV. One of the four Rotchford et al.(2) studies assessed 106 men who, as specif ied by the study protocol, had dysuria, urethral discharge, or genital ulce ration.(3) The nine men in the study who had nongonococcal urethritis were somewhat less likely than those without the disorder to be shedding HIV. Ho wever, the current authors believe this study should not be included in an analysis of chlamydial infection and HIV shedding because everyone in the c omparison group had other STD syndromes, also potentially making them more likely to be shedding HIV. For instance, 73% of the men in the comparison g roup had gonorrhea, and those with gonorrhea accounted for 83% of those who were shedding HIV. Furthermore, in that particular study, specific chlamyd ial testing was not performed, so it should not be used to address the issu e of chlamydial infection and HIV shedding. Each of the remaining three studies involved women. The largest of these st udies showed that female sex workers with chlamydial infection were three t imes more likely to be shedding HIV than those without chlamydia.(4) In the other two studies, HIV shedding was also somewhat more commonly detected a mong women with chlamydial infection than among those without chlamydia, al though these differences were not statistically significant.(5,6) However, the results pooled from these three studies showed that chlamydial infectio n was significantly associated with HIV shedding (Mantel-Haenszel odds rati o, 1.85; 95% CI, 1.1-3.2; P = 0.02). There was not substantial heterogeneit y in the results from these three studies (Breslow-Day test for heterogenei ty, P = 0.3), but meta-analysis may not be appropriate because of differenc es in study populations and methods. The current authors agree with the call of Rotchford et al(2) for additiona l high-quality studies to address this issue. In the meantime, screening, t reatment, and prevention of STDs, including chlamydial infection, remain an important part of care for HIV-infected persons.(7)