Challenging seronegative arthritis and rheumatic manifestations of syphilis: A case-based review of the great imitator

Abstract

Syphilis can have varied presentations, including rheumatological and ocular. Early recognition and treatment are necessary to prevent permanent complications. A 34-year-old married male presented with symmetric seronegative arthritis, diagnosed as rheumatoid arthritis, and not responding initially to corticosteroids and Disease-Modifying Anti-Rheumatic Drugs (DMRADs) but eventually resolved. It was followed by amaurosis fugax that lasted for three days. Magnetic Resonance Imaging (MRI) of the brain and spinal cord were normal. Aquaporin-4 antibodies were negative. Anticardiolipin IgM (55 U/ml), IgG (50.8 U/ml) and β-2 glycoprotein-I (68.6 U/ml) were positive, justifying anticoagulation. This was followed by recurrent attacks of diminution of vision and floaters in both eyes; Slit lamp examination and fluorescein angiography revealed posterior uveitis, bilateral vasculitis with leaking discs, cystoid macular edema and peripheral ischemia. He had no orogenital ulcers, lymphadenopathy, skin rashes or sicca manifestations. A serological panel of investigations for infection revealed positive Rapid Plasma Regain (RPR) (1:128), Venereal Disease Research Laboratory (VDRL) and Treponema Pallidum Hemagglutination Assay (TPHA), highly suggestive of syphilis. The patient was treated with ceftriaxone with dramatic improvement. On follow-up, the uveitis resolved with persistent peripheral ischemia, Optic Coherence Tomography (OCT) revealed bilateral dry macula, the serology and antiphospholipids dropped and tended to normalize. Syphilis may atypically present with symmetrical seronegative polyarthritis, posterior uveitis, retinal vasculitis, optic neuritis and associated positive antiphospholipid antibodies. This case contributes to increase the awareness of rheumatologists and ophthalmologists regarding the confusing clinical aspects of this great mimicking disease, syphilis.