A case and literature review of intraocular echinococcus causing bilateral visual loss in a HIV-infected patient

Although echinococcosis is a common parasitic disease endemic to Africa, ocular echinococcosis is rare. We present a case of intraocular echinococcosis in a HIV-infected patient. A 38-year-old South African HIV-infected woman presented to a district-level hospital in Kwa-Zulu Natal on 10 March 2020. Her main presenting complaint was that of progressive, painless, bilateral visual loss. A B-ultrasonography scan revealed tractional retinal detachment on the right eye, while the left eye had tractional bands with a 'double-walled' cystic cavity causing retinal traction. A systemic work-up revealed a positive Echinococcus ELISA IgG with a value of 1.3, eosinophilia of 5.70% (0.41 × 10⁹), and elevated C-reactive protein and erythrocyte sedimentation rate of 47 mg/L and 93 mm/hr, respectively. Based on the above clinical, biochemical and ultrasonographical evidence, a diagnosis of ocular echinococcosis was made. Our differential diagnosis includes toxic optic neuropathy, Jarisch-Herxheimer-like reaction secondary to immune reconstitution and necrotizing herpetic retinitis. She was initiated on topical and intravitreal steroids which led to decreased intraocular inflammation and dry maculae. Five months after presentation, her visual acuity remained unchanged with no light perception in both eyes. We conclude that ocular echinococcosis, although rare, can lead to severe visual impairment as there are no known definite treatment modalities for intraocular hydatid disease. Reports on co-infections with HIV and Echinococcus are limited with a potential scope for research.