DOI: https://doi.org/10.36347/sjmcr.2026.v14i02.033

Pages: 312-314

Introduction: IgM multiple myeloma is an extremely rare entity, accounting for less than 1% of all myelomas, and differs from Waldenström macroglobulinemia despite the shared secretion of monoclonal IgM. Its presentation with ophthalmologic involvement is exceptional and may threaten visual prognosis. Case Report: We report the case of a 38-year-old woman admitted for sudden bilateral visual acuity loss associated with headaches and constitutional symptoms. Ophthalmologic examination revealed bilateral retinal vein occlusion with papilledema and serous retinal detachment. Laboratory investigations showed profound aregenerative anemia, marked hyperproteinemia, hypercalcemia, and hyperviscosity syndrome. Serum protein electrophoresis demonstrated a massive monoclonal IgM spike. Bone marrow evaluation, including aspiration and biopsy, revealed 30% medullary plasmacytosis with CD138+ plasma cell infiltration, without diffuse lymphoplasmacytic proliferation. Testing for the MYD88 mutation, recommended to differentiate from Waldenström macroglobulinemia, could not be performed for financial reasons. Nevertheless, the overall findings supported a diagnosis of IgM multiple myeloma. The patient received chemotherapy according to the VCD protocol, with clinical, biological, and ophthalmologic improvement, followed by maintenance therapy with bortezomib and indication for autologous hematopoietic stem cell transplantation. Conclusion: Ophthalmologic involvement may reveal IgM multiple myeloma, highlighting the importance of systematic evaluation and prompt management to improve functional and overall prognosis.