The prevalence of ocular syphilis was almost twice as high among HIV-positive patients as among those who were HIV negative or HIV unknown (prevalence ratio 1.9; 95% confidence interval, 1.1 to 3.1).
Of the 1694 HIV-infected syphilis cases, 264 were diagnosed with HIV at the same time as their syphilis diagnosis, and 4.2% of the 264 cases were classified as ocular syphilis cases (prevalence ratio 2.5; 1.2 to 5.0).
Among syphilis patients with a previous HIV infection, those with OS were older than those without OS (median age 42 years vs 33 years; P
=.008), and they had a lower CD4 cell count (median 384 cells vs 521 cells/mL; P
=.03). The viral load was roughly equal between OS and non-OS patients (median 40 copies vs 20 copies/ml, P
Syphilis patients concurrently diagnosed with HIV who had OS were also older than those without OS (median age 48 years versus 27 years; P
=.0004) and had a lower CD4 cell count (260 cells vs 382 cells/mL; P
=.04). Patients with OS had a higher viral load (median 65,780 copies versus 44,024 copies/ml, P
In March 2016, the CDC issued a clinical advisory
to US clinicians urging them to be aware of ocular syphilis, screen for visual complaints in patients at risk for syphilis, and test all patients with syphilis for HIV if their status is unknown or has been negative.
"The associations we found between older age, lower CD4 counts, and the prevalence of ocular syphilis suggests that OS development may be affected by immune status," Dr. Cope said in an interview.
"All syphilis patients, especially those with ocular syphilis, should be screened for HIV," she noted.
Drs. Cope and Peterman called for further related research.
Lorraine L. Janeczko, MPH, is a medical science writer who creates news, continuing medical education and feature content in a wide range of specialties for clinicians, researchers and other readers. She has completed a Master of Public Health degree through the Department of Epidemiology of the Johns Hopkins Bloomberg School of Public Health and a Dana Postdoctoral Fellowship in Preventive Public Health Ophthalmology from the Wilmer Eye Institute, the Johns Hopkins University School of Medicine and the Bloomberg School.
DISCLOSURES: The authors of both studies and Dr. Peterman did not report any conflicts of interest with the studies.
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