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Updated: Jul 20, 2026

Procedures for In Vitro Cultivation of Treponema pallidum, the Syphilis Spirochete
Published on: January 24, 2025
Syphilis: reemergence of an old adversary
Jennifer R Chao1, Rahul N Khurana, Amani A Fawzi
1Doheny Eye Institute and the Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California 90033, USA.
Objective:
To describe the clinical findings in 4 patients with ocular syphilis and to provide a review of the recent rise in syphilis cases in the United States, along with a brief description of current diagnosis and treatment guidelines.
Design:
Retrospective, observational case series.
Participants:
Four consecutive patients who presented to our facility during a 6-month interval in 2005 with ocular syphilis.
Methods:
Review of clinical, laboratory, photographic, and angiographic records of patients with neurosyphilis who underwent intravenous penicillin G treatment.
Main Outcome Measures:
Resolution of signs and symptoms of ocular syphilis, including changes in visual acuity.
Results:
Four patients (3 male: mean age, 46 [range, 39-60 years]; 1 female: age 46 years) demonstrated cerebrospinal fluid findings consistent with neurosyphilis, as evidenced by increased leukocyte counts (>5 white blood cells/mm3), and positive Venereal Disease Research Laboratory or serum fluorescent treponemal antibody absorbed tests. All 4 patients presented with a variety of clinical findings that led to a delay in diagnosis and treatment. Two patients presented with discrete placoid lesions consistent with acute syphilitic posterior placoid chorioretinitis, a manifestation typically observed among the immunocompromised.
Conclusions:
Despite a decade of steady decline, syphilis has reemerged in the United States with outbreaks throughout the country in the past few years. Ocular findings, including posterior placoid chorioretinitis, are important diagnostic features in the early treatment of tertiary syphilis and neurosyphilis. Ophthalmologists have the opportunity to play a key role in the early diagnosis and management of this potentially fatal disease.
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