Risk of Coinfection withChlamydia trachomatisandNeisseria Gonorrhoeaein Nova Scotia

Abstract

BACKGROUND: The frequency of Chlamydia trachomatis and Neisseria gonorrhoeae coinfection can vary depending on their individual incidence and prevalence rates.OBJECTIVE: To determine the frequency ofC trachomatisandN gonorrhoeaecoinfections by evaluating the results of testing in 2007 and 2008 to better inform testing and treatment decisions.METHODS: Specimens from the same patient submitted on the same day served as the basis for the present study. The age, sex and the source of the specimen were also linked to the accession number. Infection and coinfection rates were analyzed in both males and females.RESULTS: Concurrent testing was performed on 41,567 female specimens and 1827 male specimens, of which, 1495 female samples (3.6%) tested positive forC trachomatisinfection and 88 (0.2%) tested positive forN gonorrhoeaeinfections. Only 31 females were coinfected; however, for those between 11 and 25 years of age, 25 of 61 females (40.1%) withN gonorrhoeaeinfection also tested positive forC trachomatisinfection; conversely, 25 of 1248 females (2.0%) withC trachomatisinfection also tested positive forN gonorrhoeaeinfection. For males, 213 (11.7%) tested positive forC trachomatisinfection,and 59 (3.2%) tested positive forN gonorrhoeaeinfection. In 30 males withN gonorrhoeaebetween 11 and 25 years of age, and 149 males withC trachomatis,eight coinfections were observed (26.7% and 5.3%, respectively). Of those older than 25 years of age, only five of 905 men and six of 19,465 women were coinfected. None of the 10,935 women who were 30 years of age or older had coinfections.CONCLUSION: TheN gonorrhoeaecoinfection rate in males withC trachomatismay justify empirical antimicrobials; however, in females, the proportion of coinfected may not justify empirical treatment forN gonorrhoeaeinfection when theC trachomatistest is positive andN gonorrhoeaetesting has not been performed.