Background:
While the CDC advises re-screening females for chlamydia (CT) 3 months after treatment, there are currently no re-screening recommendations for CT or gonorrhea (GC) in males despite likely high rates of re-infection and men's contribution to the spread of STIs.

Objective:
To systematically review and describe the evidence on male CT/GC re-infection, to evaluate the need for re-screening recommendations in men.

Method:
We searched PubMed and STD conference abstract books from 2000-2005 to identify studies on CT/GC re-infection of males meeting the following inclusion criteria: study had a follow-up period and the study used CT nucleic acid amplification tests. We calculated incidences and proportions of male CT/GC re-infection for each study and reported summary geometric means and standard deviations (+/- SD).

Result:
The search returned 9 prospective and 6 retrospective cohort studies. The mean proportion of men with repeat CT infection was 15.0% (+/- 8%) over follow-up periods ranging 8 weeks to 30 months and the mean incidence of CT re-infection was 44.0 (+/- 20) per 100PY. The mean proportion of men with repeat GC was 11.8% (+/- 12%) over follow-up periods ranging 8 weeks to 4.8 years and the mean incidence of GC re-infection was 23.5 (+/- 36) per 100PY. Proportions and incidences of GC/CT re-infection in men were comparable to those of women. Re-infection was strongly associated with previous STD history and younger age while inconsistently associated with risky sexual behavior.

Conclusion:
We found a substantial proportion of men were re-infected with CT/GC and the incidence of re-infection was comparable to rates in women. Re-infection was significantly associated with demographic variables but inconsistently related to sexual behavior.

Implications:
Re-screening recommendations for men with CT/GC infection should be similar to women: re-screening at 3 months. To optimize re-screening guidelines, we suggest further research to establish factors associated with and time to male re-infection.