Multiple Myeloma with Intracytoplasmic Azurophilic Granules.

Bone marrow examination plays an important role in the diagnosis of multiple myeloma. In some cases with multiple myeloma, marrow plasma cells with cytoplasmic inclusions are seen. In this study, a 46-year- old man was evaluated for multiple myeloma. In bone marrow aspiration, large intracytoplasmic azurophilic granules, resembling intracellular microorganisms were seen. IHC study demonstrated that these cells are CD138 positive. This is a rare histologic finding that usually results from the deposition of excess immunoglobulin.