A 42-year-old man presented to the ophthalmology clinic with a 1-month history of progressive blurred vision and floaters in his right eye. He had no medical history. On ocular examination, the visual acuity (VA) was 20/20 in both eyes. The anterior segment was unremarkable. Funduscopic examination of the right eye revealed active lesions with whitish foci of choroidoretinitis with surrounding edema along the superonasal vessels, and retinal vasculitis with perivascular sheathing (Figures 1A,B). Serologic testing was positive for Toxoplasma gondii IgM and IgG, HSV-1 IgG, HSV-2 IgG, and CMV IgG, and negative for syphilis and Anti-HIV. Optical coherence tomography (OCT) of the macula revealed mild perifoveal edema in the right eye. Fluorescein angiography of the right eye showed obliteration of the blood flow with a non-perfusion area and leakage at the vessel wall (Figure 1C).
Based on the patient's history, ophthalmic findings, and serology results, an infectious cause was highly suspected. We performed aqueous humor tapping for viral and tuberculosis polymerase chain reaction (PCR) testing to exclude possible causative agents. The PCR result showed no evidence of any viral or TB infection. We also performed a serum quantiferon gold test for the patient in case of recurrent tuberculosis, but the result was negative.
Thus, ocular toxoplasmosis was diagnosed. We consulted an infection specialist regarding the survey and management of potential systemic toxoplasmosis. The infection was initially managed by the infection specialist with sulfamethoxazole-trimethoprim (400/80 mg) twice per day, and one dose of dexamethasone 5 mg intravenously, on the first day. Five days later, the patient complained of significantly increasing photophobia in the lesioned eye, so we titrated sulfamethoxazole-trimethoprim (400/80 mg) to 3 times per day and added prednisolone 15 mg per day, simultaneously. Two days later, his right eye visual acuity (VA) declined to 20/100. Funduscopic examination revealed severe vitritis complicated with progressive localized retinal necrosis and multiple localized retinal breaks. Although we performed focal retinal photocoagulation immediately, he progressed to localized rhegmatogenous retinal detachment 5 days later. He then underwent a successful pars plana vitrectomy. During the surgery, we sent the vitreous samples for PCR to detect other possible pathogens, including HSV, CMV, and TB, but the results were negative. His vision improved to 20/80 after the surgery, and he has been treated with pyrimethamine plus sulfadiazine since then. The retina was attached but his VA remained at 20/80. Figure 2 showcases the timeline with relevant data from the period of care.