ocr: Rasidant and Staff Phyrican Patiant Education chart Small Kidney Stones Multiple Small Renal Calculi: If formed in the renal pelvis, these tend to be 2mm to 3mm in diameter May be rounded or jagged * May produce no symptoms Most affected age group are those 22 - to. 55 years old Most kidney stones arise in the kidney - 70%. to 80% - of stones pass during urination Reprinted with permission fom Resident and Staffi Phgsician (c)1991-92, 1993 by: Romaine Pieison Publishers,Inc.