Toxoplasma Chorioretinitis of Left Eye

An elderly patient presented with painless decreased vision in the left eye for 1 week while on chemotherapy for stage 3 non-metastatic breast cancer. A review of systems showed a recent foot infection and fungal dermatitis. Prior to presentation, the patient was treated elsewhere for acute retinal necrosis and referred for a second opinion. Best corrected visual acuity was 20/25 in the right eye and counting fingers in the left eye. Intraocular pressures were normal. Slit lamp exam showed 2+ cells in the anterior and posterior chambers and a peripheral retinal whitening nasally with patchy areas in the temporal and inferior quadrant underlying a grade 2 vitreous haze in the left eye. Right eye exam was normal. Colored fundus photo and autofluorescence also suggested an active chorioretinal necrotic lesion with an overlying vitreous opacity. Clinical findings were negative for old chorioretinal scars in both eyes. A provisional diagnosis of acute retinal necrosis was made followed by intravitreal ganciclovir/foscarnet injection and anterior chamber (AC) fluids were sent for rtPCR analysis. Blood sample was sent to rule out infectious causes and the patient was planned to continue topical steroids and oral valacyclovir 2gm three times daily. No improvement was seen during the first follow-up. Reports were negative for viral rtPCR and positive for toxoplasma gondii with raised toxoplasma IgG antibodies (106 IU/mL). Antibiotic monotherapy for toxoplasma chorioretinitis with oral sulfamethoxazole (800 mg)/trimethoprim (160mg) was started twice daily. At 1 month follow-up, the focal chorioretinal lesion with overlying vitritis was significantly reduced. The clinical picture continued to improve with a quiet AC, absent vitritis, and resolution of the chorioretinal lesion at 3 months. Despite significant clinical improvement, vision remained limited due to underlying optic nerve atrophy and degenerative macular changes.

Presentation Date: 10/26/2023

Issue Date: 12/08/2023