Sexually transmitted infections (STIs) are infections that can be passed from one person to another during sexual contact. STIs are often asymptomatic, and when left untreated can cause serious complications ranging from infertility to anogenital cancer and even premature death. Early diagnosis and treatment may reduce STI transmission and related complications.
As an alternative to universal screening for STIs — i.e., screening all people who are or have ever been sexually active — people without symptoms of STIs may be screened based on their medical history and individual risk factors.
Because many STIs are asymptomatic, especially in their early stages, infected patients often unknowingly spread infection to others and are unable to benefit from early treatment. Screening asymptomatic patients could identify STIs earlier and reduce rates of transmission and complications. A review of evidence-based algorithms for identifying STI risk factors and testing requirements in primary care, as well as the evidence-based guidelines for assessing STI risk and the timing of STI screening, will inform the development of screening decision tools.
A focused literature search was conducted of key resources, and titles and abstracts of the retrieved publications were reviewed. Full-text publications were evaluated for final article selection according to predetermined selection criteria (population, intervention, comparator, outcomes, and study designs).
The literature search identified 268 citations, with 23 additional articles being identified from a search of the grey literature. Of these, 22 met the criteria for inclusion in this review: 4 systematic reviews and 18 guidelines.
Factors to Use in Assessing STI Risk:
- sexual behaviour and orientation
- previous STI history
- pregnancy history
- substance use history
- psychosocial history
- prevalence of STIs in the population.
- screen sexually active women younger than 25 years of age for chlamydia
- screen asymptomatic adults who seek testing for an STI for all other STIs.
When Screening High-Risk, Asymptomatic Patients for STIs:
- screen men for HIV, hepatitis B, hepatitis C, and syphilis
- screen non-pregnant women for HIV, hepatitis B, hepatitis C, syphilis, gonorrhea, and chlamydia
- screen pregnant women for hepatitis C, gonorrhea, and chlamydia as well as, at early stages of pregnancy, HIV, hepatitis B, and syphilis.
Evidence ranged from strong to expert opinion.