Abstract
PURPOSE: To report a case of paracentral acute middle maculopathy as the earliest sign of an undiagnosed, life-threatening hyperviscosity syndrome. METHODS: A 78-year-old man with an acute paracentral scotoma and examination findings of bilateral arteriolar tortuosity and unilateral paracentral acute middle maculopathy. RESULTS: Work-up revealed anemia and elevated serum viscosity. Protein electrophoresis demonstrated an immunoglobulin M kappa monoclonal protein spike, and bone marrow biopsy confirmed an immunoglobulin M gammopathy consistent with Waldenström macroglobulinemia. Systemic chemotherapy was initiated. CONCLUSION: This case demonstrates typical optical coherence tomography findings of paracentral acute middle maculopathy, which led to the diagnosis of a rare lymphoproliferative disorder. This highlights the importance of a prompt work-up for paracentral acute middle maculopathy to detect underlying systemic diseases, including hyperviscosity syndromes.