Bilateral reversible optic neuropathy as the first sign of Waldenström macroglobulinema.

Objective: To report a case of bilateral reversible optic neuropathy as the first sign of Waldenström macroglobulinemia (WM).

Methods: Observational case report.

Results: A 52-year-old man had a sudden loss of vision in the left eye. Examinations revealed the presence of a serum monoclonal immunoglobulin (IgM kappa) in the serum. Even after a session of steroid pulse therapy, optic neuropathy became bilateral and then resolved almost completely after 4 months. The condition progressed to WM with multiorgan lesions years later. There was no evidence of optic neuropathy recurrence. The literature revealed two cases of monoclonal gammopathy (MG): a 64-year-old man with multiple myeloma (MM) with IgA lambda and a 51-year-old man with MM with IgG kappa. These cases have similar conditions: 1) visual reduction as an initial symptom of MG, 2) bilateral involvement, 3) no sign of central nervous system (CNS) infiltration shown by normal brain magnetic resonance images, and 4) recovery to a visual acuity of ≥1.0 bilaterally with no reoccurrence. The excessive Igs or B-cell hyperactivity may activate an autoimmune mechanism that reversibly interferes with the bilateral optic nerves.

Conclusion: Bilateral optic neuropathy was the initial symptom of WM. There was no evidence of CNS infiltration; it recovered and then did not reoccur. The pathogenesis remained unknown, but two cases of MG were reported in the literature with remarkably similar conditions.