Ocular pathology in light chain deposition disease.

Light-chain deposition disease (LCDD), a rare form of monoclonal gammopathy, is characterized by deposits of amorphous light-chain material, mainly in the kidneys but also in various other organs. Here we present the first report of a light-, electron microscopic and immunohistochemical study of the globes of a patient suffering from LCDD secondary to multiple myeloma. Massive deposits of kappa light chains similar to those typically present in the kidneys were found beneath the basement membrane of the ciliary pigment epithelium, on vessels of the ciliary body, within the collagenous zones of Bruch's membrane, and in the innermost part of the choroid. The choriocapillaris in the macular area was partly obstructed by these deposits, and an exudative retinal detachment was present. Whether this detachment was the consequence of disturbed circulation of the choriocapillaris remains speculative.