Many things can cause kidney pain. It can be due to health problems such as:

1. Bleeding in the kidney, also called a hemorrhage.
2. Blood clots in kidney veins, also called renal vein thrombosis.
3. Dehydration — when the body doesn't have enough water and other fluids to work as it should.
4. Kidney cysts (fluid-filled pouches that form on or in the kidneys)
5. Kidney stones (Hard buildups of minerals and salt that form inside the kidneys.)
6. Kidney trauma, which could be caused by an accident, a fall or contact sports.

Some diseases that can cause kidney pain are:

1. Hydronephrosis (which is swelling in one or both kidneys)
2. Kidney cancer or a kidney tumor
3. Kidney infection (also called pyelonephritis)
4. Polycystic kidney disease (a genetic illness that causes cysts to form in the kidneys)

You could have one of these health problems and not have kidney pain. For example, most kidney cancers don't cause symptoms until they're advanced.