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
4. Kidney cysts (fluid-filled pouches that form on or in the kidneys)
5. Kidney stones
6. Kidney injury (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
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.