Ocular syphilis characterised by severe scleritis in a patient infected with HIV

Abstract

A 71-year-old man presented with decreased vision and red eye in his left eye that had lasted for 1 month. He was diagnosed as HIV-positive 2 years previously and had received highly active antiretroviral therapy (HAART). Visual acuity was hand motion only, and conjunctival injection and chemosis were noted (fi gure, A). A fundus examination showed prominent vitritis, and sectorial haemorrhagic retinitis in the superonasal periphery, which was much the same as viral retinitis (fi gure, B). After 5 days, the visual acuity had decreased to light perception, and the retinal lesion had enlarged and was protruding (fi gure, C). A viral PCR of the aqueous humour was negative. The patient’s CD4 cell count was 377 cells per μL. Rapid plasma reagin and fl uorescent treponemal antibody absorbed tests of the serum were positive. 5 days after intravenous penicillin G was given, the infl ammatory reaction substantially improved (fi gure, D, E). At 6 months, the eye had no infl ammation, and the patient’s vision was 20/50 (fi gure, F). His CD4 cell count was 517 cells per μL, and the patient’s condition was stable without any complications. Ocular syphilis is known as a great imitator and does not have a pathognomonic ocular feature. It can involve the entire ocular section, and its clinical manifestations can include scleritis, iritis, chorioretinitis, and optic neuritis. Retinitis in patients infected with HIV can be associated with various ocular infections such as viral retinitis, toxoplasmosis, and syphilis. Delayed diagnosis and treatment of retinitis can lead to permanent visual impairment. Clinical manifestations and the immune status of the patient can provide clues to help with the diff erential diagnosis. Cytomegalovirus retinitis, which is the most common opportunistic infection in the HIV population despite HAART, usually develops in quiet eyes (those with a clear cornea without redness or irritation of the conjunctiva or sclera) with lower CD4 cell counts. In our patient, severe scleritis was a characteristic presenting sign distinguishable from cytomegalovirus retinitis. The possibility of ocular syphilis should be considered in a diff erential diagnosis of retinitis in an infl amed red eye in HIV-positive patients receiving HAART, to ensure early diagnosis and treatment.