Bilateral exudative retinal detachment with subretinal light-chain protein in a patient with multiple myeloma -case report

Exudative retinal detachment in patients with multiple myeloma is exceedingly rare. Only two Cases are known to us. We successfully identified light-chain proteins in subretinal fluid, allowing for a more precise understanding of the pathogenesis of this complication. A 68-year-old patient presented with bilateral exudative retinal detachment. The visual impairment was reported one day after stem cell mobilization by granulocyte-colony stimulating factor (G-CSF) and the additional administration of Plerixafor. The symptoms began during stem cell apheresis. The patient underwent surgical treatment for both eyes through vitrectomy and silicone oil tamponade. Light-chain proteins were detected in the collected subretinal fluid through electrophoresis in one eye. We successfully identified light-chain proteins in subretinal fluid, allowing for a more precise understanding of the pathogenesis of this complication. The pathomechanism likely involves damage to the outer blood-retina barrier due to the deposition of light-chain proteins. Whether mobilization of bone marrow cells with Plerixafor led to a breakdown of the outer blood-retina barrier in these patients is a topic for discussion and has to be considered in the use of Plerixafor.