MYOM2 and autoimmune disease: In this case, the ratio was 0.13, falling outside of the renal reference interval (0.37–3.1).13 In addition to renal impairment, inflammatory disorders such as autoimmune diseases have been identified as causes for elevated SFLC concentrations and a normal to mildly raised κ/λ ratio due to polyclonal increases in light chain production.21,22 In our study, many patients with normal renal function, abnormal SFLC ratio and absent M-protein had a polyclonal increase in gamma globulins on SPE.