La ocular syphilis is an inflammatory disease of the eye which develops as a result of infection by Treponema pallidum. This micro-organism is the aetiological agent of the syphilis, a sexually transmitted infectious disease that evolves through four stages. The first stage is characterised by venereal lesions (ulcers) that may not be painful, but are very infectious; the second stage presents a series of general symptoms (headache, fatigue, fever, etc.) that often lead to diagnostic errors; the third stage, called latent, shows no symptoms but the micro-organism is detectable in body fluids; finally, the fourth stage, also known as tertiary stage, may present itself even decades after infection and may involve the central nervous system or the cardiovascular system with very serious consequences.
La ocular syphilis is relatively rare, but can develop at any stage of syphilis e involve all the structures of the eyeleading to interstitial keratitis, chorioretinitis, retinitis, retinal vasculitis and neuropathy of the cranial nerves and optic nerve. Patients with ocular syphilis are also at risk of neurosyphilis.
The recently provided guidelines by the World Health Organisation (WHO) indicate a global increase in the incidence of syphilis. The re-emergence of the disease has been attributed to several factors including: the increase in high-risk sexual practices and global travel, the effects that anti-HIV drugs can have on the immune system (co-infection with HIV/ T. pallidum), and to the changes in antibiotic sensitivity by T. pallidum.
The increased prevalence of syphilis has led, inevitably, to the increase in eye shape mimicking the symptoms of various eye disorders, often is not promptly diagnosed and treatedleading to serious consequences including blindness.
A team of researchers, from the University of São Paulo in Brazil and Flinders University in Australia, analysed 127 patients with ocular syphilis and found ocular inflammation or uveitis in both eyes in 87 of them; half of the patients were so severely affected that they were unable to drive. This recently published study also highlighted a number of complications resulting from ocular syphilis, the most common of which are loss of vision, cataracts and ocular hypertension (increased pressure in the eye that can lead to glaucoma or loss of vision). The patient undergoing treatment may experience improvements in vision, but the damage may become permanent if therapy is not started in a timely manner. Â
The guidelines indicate as a therapy for the infection the use of penicillin; dosage and duration of treatment depend on the stage of the disease and its clinical manifestations.
Several studies and reports have shown a rise of ocular syphilis also in Europeespecially in urban areas and in individuals at risk for co-infection with HIV. Following the recent epidemiological awakening of T. pallidumIt would therefore be important to consider, when diagnosing ocular inflammation, the possibility of ocular syphilis for which early treatment is of paramount importance for an optimal outcome.
Sources
-Clinical Manifestations and Outcomes of Syphilis-associated Uveitis in Northern Spain. Fonollosa A et al. Ocul Immunol Inflamm. 2016.
-Clinical Manifestations and Ophthalmic Outcomes of Ocular Syphilis at a Time of Re-Emergence of the Systemic Infection. João M. Furtadoet al. Scientific Report, 2018.
-http://www.epicentro.iss.it/problemi/sifilide/sifilide.asp
Dr. Carmelo Chines
Direttore responsabile