I have often seen patients with chronic kidney disease who have an abnormal serum protein electrophoresis (SPEP) or free light chain (FLC) ratio and are referred to hematology before a nephrology evaluation. Many undergo an extensive hematologic workup, including a bone marrow biopsy, before their kidney disease is assessed. If the biopsy is negative for multiple myeloma or other hematologic malignancy, the abnormal monoclonal studies are attributed to monoclonal gammopathy o