Objective: To study the changes of serum cystatin C( Cys C),creatinine( Cr) and lactate dehydrogenase( LDH) in patients with multiple myeloma at early stage of renal injury,so as to provide references for clinical diagnosis. Methods: The clinical data of 40 patients with multiple myeloma admitted to our hospital from January 2016 to January 2018 in our hospital were retrospectively analyzed,and 40 healthy volunteers in the same period were selected as control group. The serum levels of Cys C,Cr and LDH were...