Ocular manifestations of Rickettsiosis: 2. Retinal involvement and treatment

The presence of retinitis, retinal vasculitis, optic neuropathy, or any intraocular inflammatory condition in a patient with fever or rash, living in or returning from from an endemic area, especially during spring or summer, strongly suggests a diagnosis of Rickettsiosis. Systemic fundus examination, complemented with fluorescein angiography and ICG angiography in selected cases, may help establish the diagnosis of rickettsiosis while serologic testing is pending. Prevention is the mainstay of the disease control i.e. personal prevention against tick bites in endemic areas and improvement of sanitary conditions. In patients with rickettsiosis retinal vascular involvement may present different clinical pictures: branch retinal artery occlusion, cystoid macular oedema, serous retinal detachment, and hypofluorescent choroidal spots. [1] Rickettsial retinitis presents as white retinal lesions that are typically juxtavascular in location and are associated with mild vitreitis. Differential diagnosis with Toxoplasmosis is often required. Large foci tend to involve all retinal layers extending to the retinal pigment epithelium and more deeply until the choroid. Small foci may also involve the entire retinal thickness, but in some cases only superficial retinal layers are involved and lesions resemble cotton-wool spots. White retinal lesions may number from 1 to more than 5, may be variable in size and located at the periphery or posteriorly. If the optic disk is involved, there may be disc oedema and staining. [2]