Do kidney stones that do not cause any pain, need to be removed?

Q: Few years back my father was diagnosed with kidney stones. The USG report was as follows: Left kidney shows large 3.2 x 1.2 cm staghorn calculus in renal pelvis and middle calyx with few small calculi in upper and lower calyces. But my father never felt any sort of pain or disorder. Doctors advised that if the stones do not cause any pain, then there is no need for surgery. Recently my father felt unconscious & nauseated & was diagnosed as having acute spondylosis. This has improved but he faces the problem of vomiting, after 7 to 10 days. Does the vomiting have any connection with the kidney stone? Is it advisable under above circumstances to leave the kidney stone as it is or should it be removed?

A:Large kidney stones do not cause pain as these stones cannot move in the small urinary passages. Only small stones while moving in the urinary passages cause pain called renal / ureteric colic. As stones become bigger they do not cause pain but they slowly and steadily lead to destruction of functioning kidney, can also lead to infection and occasionally to cancer. Thus stones should be removed.The vomiting may not be related to the stone disease but due to spondylosis.