Two Cases of Paraproteinemic Keratopathy

Purpose: To report two cases of paraproteinemic keratopathy (PK).Case summary: A 57-year-old man visited the ophthalmology clinic complaining of decreased visual acuity since 1 year earlier. White crystalline deposits were observed on both corneas and the best corrected visual acuity (BCVA) of both eyes was 1.0. After 3 months, the BCVA decreased to 0.8 in the right and 0.6 in the left. Increased corneal deposits were observed. To rule out PK, his medical records were checked. The patient had been diagnosed with lymphoplasmacytic lymphoma 3 years earlier. Diagnosing PK, the patient was referred back to the Hemato-Oncology department. After 3 months of chemotherapy, the corneal deposits decreased and BCVA returned to 1.0. A 69-year-old woman presented complaining of decreased visual acuity for 2 years. The uncorrected visual acuity (UCVA) was 0.4 in the right and finger count at 30 cm in the left. Brown deposits were ob-served on both corneas and lenses. The serum copper level was elevated. She was referred to the internal medicine department and diagnosed with multiple myeloma. After treatment, the laboratory results returned to normal, but the UCVA decreased to hand motion in the left. A left white cataract was noted and cataract surgery was performed. 1 month postoperatively, the BCVA was 0.9, with no change in the corneal deposits.Conclusions: When there are corneal deposits, we should consider PK in the differential diagnosis. In such cases, systemic treatment is the first line. Therefore, diagnosing and referring PK patients to the internal medicine department is crucial.