ED Syphilis Screening Boosts Surveillance, Diagnoses

An emergency department (ED) opt-out testing strategy led to big increases in syphilis screening and diagnosis in the Chicago area, according to the results of a new study. Newly diagnosed cases were generally asymptomatic, highlighting the potential of such a strategy to catch cases early and prevent complications.

The study was published online in Open Forum Infectious Diseases. The results come as cases of adult and congenital syphilis are on the rise, with the US Centers for Disease Control and Prevention estimating increases of 80% and 183%, respectively, between 2018 and 2022. That rise may be due to a combination of factors that might include the COVID-19 pandemic, reduced access to services, closure of sexually-transmitted infection clinics, and fewer worries about HIV following the introduction of pre-exposure prophylaxis, according to study author Kimberly Stanford, MD.

“I think with syphilis in particular, we a little bit let our guard down. It kind of snuck up on us again,” said Stanford, who is an associate professor of medicine and director of ED HIV/STI Testing and the ED Social Medicine Team, Biological Sciences Division, The University of Chicago Medicine, Chicago.

The new approach is based on opt-out screening for HIV, which removes both stigma and potential bias of testing, according to Stanford. “That’s worked really well for HIV because it’s gotten to a population of people who wouldn’t have themselves thought they were at risk, and the people doing the screening wouldn’t have thought they were at risk, and it really makes it a lot easier. There are a lot of similarities between syphilis and HIV, both in the populations that it affects and also in the fact that they could both be asymptomatic for a long time,” said Stanford.

The testing protocol called for offering syphilis screening to anyone between the ages of 18 and 64 with no HIV diagnosis and no history of HIV screening in the past 12 months, as well as based on clinical discretion. The researchers compared data from 2 years before the intervention was implemented and the first 2 years afterwards, between June 2017 and May 2021. It included a total of 299,651 ED encounters.

Before the screening intervention, 3.6% of ED encounters led to syphilis tests, and this number rose to 24.4% after the screening strategy began. The researchers identified 161 patients with presumed syphilis infection before the intervention and 624 afterwards. Among those who were pregnant, the screening rate jumped from 5.9% to 49.9% and presumed cases increased from 2 to 15.

Such a screening strategy, widely implemented, could have a big impact on syphilis rates, said Stanford. She is particularly affected by congenital syphilis. “It’s really upsetting because it’s a very treatable and preventable condition, and I think we really have an opportunity here to reach people, to get them diagnosed and treated before it gets to that point. Since we implemented this program, we have been seeing increased rates of neurosyphilis. I’ve seen people with colitis and pancreatitis who went all the way through to the point of getting a colonoscopy, trying to figure out what was going on, and then it ended up being syphilis. I think we’re now starting to see some of those things getting diagnosed a little bit earlier because of this screening program,” she said.

Stanford acknowledged that the test puts an additional burden on ED personnel. False positives can occur due to previously treated infections, requiring contact with patients or access to medical records to confirm a result.

One important limitation of the study was that testing was conducted at a single site and may not be generalizable to other EDs, according to Carolyn Deal, PhD, who served as a program official for the study. She also noted that the study was affected by the COVID-19 pandemic. “It’s not known how the pandemic could have impacted the study results,” Deal said in an email response. She is chief of the Enteric and Sexually Transmitted Infections Branch, Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases.

“I thought it was a really clever way to implement a screening program in an academic health system,” said Paul Adamson, MD, who was asked to comment. “In fact, it’s something that we’ve also been interested in researching (at UCLA) as well. I think it showed that we can improve syphilis screening in hard-to-reach populations, and it was a relatively simple intervention,” said Adamson, who is an assistant clinical professor at the David Geffen School of Medicine at UCLA.

Adamson agreed that the test would add a burden to ED providers who are already overworked. “On the other hand, emergency room providers I think understand the epidemic of HIV, and also maybe to a lesser extent syphilis, but with some education could I think be convinced that this is a worthwhile activity to do,” he said.

“It does require buy-in from [infectious disease] providers who, frankly, are also overworked and overburdened. I think people all agree that this is a problem that’s worth solving, so I think people will be on board with it. Personally, I think there should be a way to incentivize this, to have it either be some kind of quality metric, or a public health system payout to emergency departments for identifying cases,” said Adamson.

Adamson and Stanford had no relevant financial disclosures.