Chikungunya fever is a potentially fatal illness resembling dengue fever that is caused by an arthropod-borne Alphavirus. Patients present with fever, headache, fatigue, nausea, vomiting, myalgia, arthralgia, and skin rash. Chikungunya translates to “that which bends up,” a reference to the polyarthropathy, tenosynovitis, and stooped posture of some affected patients. The virus is typically transmited to humans via mosquito bite. Maternal-fetal transmission has been documented. Recent outbreaks have occurred in Africa, Asia, Europe, and the Americas.
The ocular manifestations in a 2006 epidemic in India included both anterior uveitis and retinitis, and, less frequently, nodular episcleritis. Each had a typically benign course. The anterior uveitis may be granulomatous or nongranulomatous and associated with diffuse pigmented KPs, iris pigment release, and elevated IOP. Chikungunya retinitis may resemble herpetic retinitis. However, chikungunya retinitis features focal, multifocal, or confluent retinochoroiditis in the posterior pole with retinal hemorrhage and minimal vitritis (Fig 11-19), while herpetic retinitis includes the peripheral retina and a more intense vitritis.
Figure 11-19 Retinitis associated with chikungunya fever. A, Retinitis with hemorrhages, right eye. B, Multifocal retinitis, left eye.
(Reprinted with permission from Mahendradas P, Ranganna SK, Shetty R, et al. Ocular manifestations associated with chikungunya. Ophthalmology. 2008;115:287–291.)
Diagnosis may be confirmed serologically by IgM antibodies, virus isolation, or PCR. Although retinitis has been treated with systemic acyclovir and prednisone, there is no evidence to suggest that such therapy improves visual outcome.
Excerpted from BCSC 2020-2021 series: Section 9 - Uveitis and Ocular Inflammation. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.