Multiple Myeloma Presenting with Crystal Deposition in the Bone Marrow

Monoclonal immunoglobulin deposition disease (MIDD) is characterized by the deposition of amorphous non-congophilic materials predominantly in the kidneys leading to nephrotic syndrome or renal failure. As with light chain amyloidosis. MIDD is associated with a paraproteinemia. We report a patient suffering from multiple myeloma with IgG kappa paraproteinemia and immunoglobulin deposits predominantly in the bone marrow. The deposits are both as amorphous non-congophilic materials, and in the form of crystals, an observation not reported before.