A team of physicians from Emory University School of Medicine evaluated Ebola virus survivors at a hospital in Liberia and found the prevalence of uveitis was 22%, comparable to a previous series from a clinic in Sierra Leone that reported a rate between 18% and 34%.
The high risk of a potentially blinding disease in Ebola survivors underscores the importance of ophthalmic screening and treatment in this population. In addition, this study shows that more work needs to be done to determine the appropriate treatment for Ebola-associated uveitis, as well as the appropriate protective equipment for caregivers and family members.
The 2015 outbreak resulted in more than 10,000 cases of Ebola virus in Liberia alone, and resulted in 4,809 deaths. The magnitude of the outbreak created the largest cohort of Ebola survivors in history. An ophthalmology clinic was established in Liberia in partnership with Emory Eye Center health care providers and the Eternal Love Winning Africa Hospital in April 2015, where patients were evaluated, treated or referred as needed by examining ophthalmologists.
Of the 96 survivors seen in April 2015, 22% had uveitis. Almost 40% were blind, with visual acuity greater than 20/400. Most (57%) had posterior uveitis, 29% had panuveitis and 14% had anterior uveitis. Three of the patients developed optic neuropathy, exhibiting visual impairment than ranged from 20/20 to hand motions, underscoring the breadth of pathology that may be observed after Ebola. Other findings associated with moderate visual impairment (VA <20/70) included keratic precipitates, posterior synechiae, vitritis and chorioretinal scars that were hyperpigmented with a hypopigmented halo.
In this interview, Dr. Steven Yeh discusses the spectrum of disease conditions associated with Ebola virus infection.
Age, gender, systemic and ocular symptoms, and number of days in the Ebola Treatment Unit did not differ between patients who developed uveitis compared with those who did not.
Several caveats apply to this uncontrolled, single-center case series. Because the prevalence of uveitis in the Liberian population is unknown, it is unclear whether the uveitis detected was due to Ebola or another cause such as toxoplasmosis. Furthermore, this study used the number of days in a treatment unit as a surrogate for acute virus severity, which may be an inaccurate indication of disease severity. Two other markers, PCR cycle threshold (Ct) number or viral load, may be better indicators of Ebola-associated uveitis.