High Rates of Subsequent Asymptomatic Sexually Transmitted Infections and Risky Sexual Behavior in Patients Initially Presenting With Primary Human Immunodeficiency Virus-1 Infection.

BACKGROUND

Knowledge of the risk factors of individuals with an asymptomatic sexually transmitted infection (STI) is essential for implementation of targeted STI screening strategies.

METHODS

Between June 2015 and January 2017, an STI screening was offered to all participants in the Zurich Primary human immunodeficiency virus (HIV)-1 Infection study. Patients were tested for gonorrhea, chlamydia, syphilis, and hepatitis C virus (HCV).

RESULTS

Of 214 participants, 174 (81%) were screened at least once. Most patients were men who have sex with men (MSM) (87.4%). Presenting with a primary HIV infection was associated with higher odds for later risky sexual behavior, as compared with presenting in the chronic phase (odds ratio [OR], 5.58; 95% confidence interval [CI], 3.68-8.8). In total, 79 STIs were detected, reflecting a high period prevalence of 33.3% (58 of 174 patients). Sixty-six percent of patients (52 of 79) were asymptomatic. Most common STIs were chlamydia (50.6%; 40 of 79 patients), gonorrhea (25.3%; 20 of 79), and syphilis (19%; 15 of 79). In a multivariable model, engaging in insertive (OR, 6.48; 95% CI, 1.14-36.76) or both insertive and receptive (4.61; 1.01-20.96) anal intercourse, STI symptoms (3.4; 1.68-6.89), and condomless sex (2.06; 1.14-3.74) were positively correlated with a positive screening result. The hazard of an incident STI increased with the presence of STI symptoms (hazard ratio, 3.03; 95% CI, 1.17-7.84) and any recent drug use (2.63; 1-6.9).

CONCLUSIONS

A trimonthly STI screening including asymptomatic individuals should be considered in this population, particularly in MSM who report sexual risk behavior.

CLINICAL TRIAL REGISTRATION: NCT 00537966.