Doxy-PEP: A Missed Opportunity in STI Prevention?

One of the highlighted presentations focused on the implementation and effectiveness of doxycycline post-exposure prophylaxis (doxy-PEP) in the Detroit metropolitan area. Christen Arena,from Henry Ford Hospital’s Department of Pharmacy,presented data on a program initiated in May 2023. The program aimed to leverage doxycycline’s proven ability to reduce infections caused by syphilis, chlamydia, and gonorrhea.

The Detroit program established a prescription module with predetermined guidelines and doses,empowering infectious disease doctors,primary care physicians,and nurse practitioners to prescribe doxy-PEP. Patients were instructed to self-administer 200 mg of doxycycline within 72 hours of engaging in high-risk sexual activity.

The target population, as defined by Centers for Disease Control and Prevention (CDC) guidelines, included men who identify as gay, bisexual, other men who have sex with men, and transgender women with a history of at least one bacterial STI in the past 12 months. Currently, there is no recommendation for cisgender women, heterosexual men, or other queer individuals due to lack of evidence.

Despite the potential benefits, the Detroit program revealed a significant gap in utilization. Only about 7% of the 312 PEP prescriptions made during the study period were given to patients who met the criteria for doxy-PEP candidates. Of those, only one patient tested positive for syphilis.

It appears that this regimen could be effective, but it is indeed underutilized.

This finding underscores the need for increased awareness and implementation of doxy-PEP as a preventive measure, particularly among high-risk populations.

Gonorrhea: Bacterial Load and Symptom Correlation

the second noteworthy presentation, delivered by Dr. Guillaume Beraud, professor of infectious diseases at the Orléans University Hospital in France, explored the relationship between gonococcal bacterial load and symptoms. The study, titled “Gonococcal Bacterial load Measured by Ct (Cycle Threshold) in Urine Samples Correlates with Symptoms,” addressed a common clinical dilemma: how to manage asymptomatic gonococcal infections.

While symptomatic patients require treatment, the management of asymptomatic cases, which account for more than 10% of infections, remains less clear. The researchers investigated whether bacterial load, measured by Ct value from PCR testing of urine, could serve as a reliable indicator of patient infectivity and correlate with the presence of symptoms.

The study involved 301 men who tested positive for Neisseria gonorrhoeae in urine PCR tests between 2019 and 2024 and had not received antibiotics in the previous 7 days. The researchers found that bacterial load did not correlate with baseline patient characteristics such as sexual orientation,number of sexual partners,or previous gonococcal infection history.

However, a significant finding emerged: asymptomatic patients (21% of the total) had higher Ct values, indicating a lower bacterial load.

patients who are asymptomatic (21% of the total) had higher Ct values,indicating a lower bacterial load.

The implications of this finding are significant. While the role of bacterial load in transmission remains unclear, the study raises the possibility that patients with lower bacterial loads may be less infectious.

The role of bacterial load in transmission remains unclear, and it is not yet established whether a lower bacterial load implies lower infectivity, supporting the hypothesis that these patients may potentially be left untreated.

Further research is needed to determine whether bacterial load can be used to guide treatment decisions for asymptomatic gonococcal infections.