PROS1 and Fanconi renotubular syndrome: To the best of our knowledge, only 11 cases of crystalline inclusion within the podocytes associated with plasma cell dyscrasia have been reported.[4,5–15] Of these, nine had multiple myeloma,[5,6,8,9,11–15] and two MGUS.[7,10] Interestingly, all cases had IgG-κ M-protein, with only one case exceptionally manifesting clinical manifestations of Fanconi syndrome.[11] Proteinuria is a representative clinical feature of crystalline podocytopathy.