The pathology and pathogenesis of retinal vasculitis

Abstract

Retinal vasculitis is a rare, but potentially blinding intraocular inflammatory condition with diverse aetiology. Although commonly idiopathic, it has a strong association with systemic inflammatory diseases known to involve other areas of the central nervous system, most notably Behcet's disease, sarcoidosis, systemic lupus erythematosis and multiple sclerosis. This article describes the clinicopathologic features of retinal vasculitis and its visually damaging sequelae, reviewing available human histopathologic studies and work with experimental models to discuss the pathogenesis and immunopathology. Evidence indicates that noninfective retinal vasculitis is an autoimmune condition that may be induced by antecedent infection with microbes cross-reacting with putative autoantigens, influenced by genetic susceptibility of both HLA associations and cytokine polymorphisms. The growing understanding of the cellular mechanisms involved in the effector immune response is already providing a rationale for more specific therapeutic approaches.

A case of vasculitis, retinitis and macular neurosensory detachment presenting post typhoid fever

“…Anecdotal similarly reported [5] cases have been assumed to be due to retinal infiltration of immune origin. Pathogenesis of immune-mediated vasculitis could be attributed to post infectious immunologic effects which may lead to an immune response that reacts to self-antigens (for example, heat shock protein and myelin basic protein) or homology between retinal antigens and microbial peptides (similarity between S antigen and microbial peptides like yeasts, Escherichia coli , and hepatitis B virus) or molecular mimicry leading to autoimmunity (S antigen and interphotoreceptor retinoid binding protein - IRBP) [7]. Diagnosis of immune-mediated retinitis is often clinical, based on past history of a febrile illness (4 to 6 weeks prior) and is supplemented by laboratory workup.…”

Microglial Activation in Human Diabetic Retinopathy

“…Retinal perivasculitis, as seen in sarcoidosis, tuberculosis, and certain forms of uveitis, exhibits cuffing of retinal vessels by lymphocytes and mononuclear cells. 12 The cuffing of retinal vasculature by activated microglia has not been previously described. Cunha-Vaz 13 described leakage of fluorescein from retinal vasculature in the earliest stage of diabetic retinopathy before structural changes took place in the retina vessels.…”

Imaging Retinal Vascular Changes in Uveitis

“…4,5 A number of studies have also demonstrated the presence of CD4 + T cells within and surrounding the retinal vessels in patients with retinal vasculitis. 1,2,6 Thus, cell-mediated immunity seems to play a role in pathogenesis. This is in contrast to classic forms of systemic vasculitis such as SLE where a type III hypersensitivity reaction deposits immune complexes within the vessel wall followed by fibrinoid necrosis.…”