The symptoms of kidney stones depend on the size and shape of the stone, as well as its location in the kidney, whether there are infections, obstructions, and other factors. Smaller kidney stones, which are smooth, can be expelled with the urine without causing noticeable symptoms. Stones lodged in the lower part of the renal pelvis or in the calyces can be asymptomatic. If the kidney stones are larger, located in the calyces or the renal pelvis, they can compress the kidney and cause back pain or dull pain because the stones can lead to the dilation or obstruction of the renal pelvis or kidney. Patients may experience back pain, fever, and if there is an infection, localized fever may occur. Additionally, kidney stones can scratch the mucous membrane of the ureter or kidney, causing bleeding.