RESUMEN
PURPOSE: To study the biochemical analysis of aqueous humor in a patient with multiple myeloma presenting first as chronic uveitis. METHODS: Observational case report. RESULTS: A 63-year-old healthy woman presented with blurred vision in both eyes for 9 months. Slit-lamp examination showed bilateral conjunctival congestion, corneal oedema, and anterior uveitis. Fundus exam revealed normal optic disc with fine retinal folds in the macula. Serum protein electrophoretogram showed a monoclonal M protein band in the gamma globulin region. The bone marrow biopsy revealed hypercellular marrow with trilineage haematopoiesis and the bone marrow aspirate showed clonal plasma cells >10%, confirming the diagnosis of multiple myeloma. Aqueous fluid showed a differential band in electrophoretic profile of aqueous humor protein that on mass spectrometry analysis was strongly suggestive of immunoglobulin band. CONCLUSION: The biochemical analysis of aqueous humor is another diagnostic test to monitor M protein in patients with multiple myeloma.