Histopathological changes in the eyes in systemic lupus erythematosus: an electron microscope and immunohistochemical study

Abstract

This paper reports the histopathological findings in the eyes of a 26-year-old female patient diagnosed with systemic lupus erythematosus (SLE) with peripheral neuropathy. The patient had no significant ocular problems. She died of pneumonia after two years of suffering. The eyeballs were procured at autopsy and the retina, choroid and optic nerve processed for light and electron microscopy, and immunohistochemistry for immunoglobulin G (IgG), glial fibrillary acidic protein (GFAP), calbindin and parvalbumin. Histologically, there was haemorrhaging in the retinal nerve fibre layer. Ultrastructurally, the axons of this layer were swollen, and contained an unusual accumulation of microtubules and smooth endoplasmic reticulum. There were degenerative changes in the pericytes and smooth muscle cells of blood vessels. The capillary lumen was partially obliterated, and contained IgG, which was also detected throughout the choroid and wall of choroidal arterioles. The latter and Bruch's membrane showed fibrin deposits. The optic nerve showed infiltrated mononuclear cells near the degenerated axons, these axons lacked immunoreactivity to calbindin and parvalbumin. Compared to the control, the connective tissue sheaths of the central retinal vessels possessed a vast number of proliferated fibroblast cells, and trichrome staining showed transmural vessel scarring. Dense GFAP immunoreactivity was observed surrounding the vessel wall. These pathological changes are due to impaired blood circulation caused by haemorrhaging and vasculitis, and vessel occlusion by fibrin. The nature of the changes observed tends to indicate that a regular, thorough ophthalmic examination should be conducted even in the absence of significant ocular symptoms in SLE.