The Chlamydia trachomatis Plasmid and CT135 Virulence Factors Are Not Essential for Genital Tract Infection or Pathology in Female Pig-Tailed Macaques.

The Chlamydia trachomatis plasmid and inclusion membrane protein CT135 are virulence factors in the pathogenesis of murine female genital tract infection. To determine if these virulence factors play a similar role in female nonhuman primates, we infected pig-tailed macaques with the same C. trachomatis strains shown to be important in the murine model. Wild-type C. trachomatis and its isogenic mutant strain deficient in both plasmid and CT135 were used to infect macaques. Macaques were given primary and repeated cervicovaginal challenges with the wild-type and mutant strains. The infection rate, infection duration, and antibody response were similar among macaques infected with both strains. Unexpectedly, colposcopy, laparoscopy, and histologic analysis revealed no substantial genital tract pathology following either primary or repeated cervicovaginal challenges. Cytokine analysis of cervicovaginal secretions from both challenged groups revealed low concentrations of interleukin 1ß (IL-1ß) and elevated levels of the interleukin 1 receptor agonist (IL-1RA). We propose that an imbalance of IL-1ß and IL-1RA in macaques is the reason for the mild inflammatory responses observed in infected urogenital tissues. Thus, understanding the pathobiology of chlamydial infection requires a better understanding of host epigenetic and chlamydial genetic factors. Our findings also have implications for understanding the high frequency of asymptomatic infections in humans.

Positive predictive value of Gen-Probe APTIMA Combo 2 testing for Neisseria gonorrhoeae in a population of women with low prevalence of N. gonorrhoeae infection.

We collected specimens from women who tested positive for Neisseria gonorrhoeae using the Gen-Probe APTIMA Combo 2 (AC2), and we performed confirmatory tests using a nucleic acid amplification test (NAAT) that targets alternate gonococcal nucleic acid sequences. Among 59,664 specimens, 280 (0.47%) had positive results using AC2; 265 of these specimens were tested using the confirmatory NAAT, of which 258 yielded positive results (positive predictive value, 97.4%; 95% confidence interval, 95.1%-98.8%). Routine confirmatory testing of specimens with positive AC2 gonorrhea test results is not indicated.