Blood sedimentation is a relatively simple test that is not very specific, but it is often used in kidney examinations. When an abnormally elevated sedimentation is found to be greater than 80 mm/h or even 100 mm/h, care should be taken to rule out the consideration of SLE, tuberculosis, and renal damage from multiple myeloma. Multiple myeloma is a tumor of the hematological system, the incidence of which has increased in recent years. Clues suggesting multiple myeloma and its renal damage include: 1. proteinuria in patients over 50 years of age; 2. immunoglobulins found to be significantly elevated in the five immune tests; 3. anemia and bleeding tendency not parallel to renal failure; 4. unexplained glycosuria, amino aciduria, phosphaturia, loss of bicarbonate, urinary increased uric acid, and may present with polyuria, hypokalemia and hyperchloremic acidosis, renal bone disease (osteochondrosis); 5, positive urine periprotein (special medical term that has nothing to do with Sunday); (6) unexplained hypercalcemia or hypercalciuria with renal failure. Anyone with one or more of the above manifestations should do relevant clinical and laboratory tests carefully to exclude the possibility of multiple myeloma and to differentiate it from other diseases that can cause the above conditions. After suspecting renal damage of multiple myeloma, according to: 1) plasma protein electrophoresis with iso-M protein, abnormally high serum single immunoglobulin or light chain, and significantly decreased other immunoglobulins; 2) radiographs suggesting osteolytic damage of flat bone; 3) bone marrow smear with abnormal plasma cells greater than 15%. If at least two of the three items are positive, the diagnosis of multiple myeloma can be made clinically.