<prompt> Multiple myeloma is diagnosed by-24 hours urine proteinKidney biopsy10 plasmacytosisRouleaux formation in blood  <response>: Multiple myeloma is diagnosed by marrow plasmacytosis of 1.more than 10 and 2.radiological evidence of lytic Bony lesions and 3. demonstration of Serum and urine and component Reference textbook of Pathology 7th edition author Harsha Mohan page number 363 