Kidney calcification foci can be caused by abnormal deposits of calcium in the kidneys, or they can be kidney stones. Normally, calcium is only deposited into the bones, so the bones appear to be hard so that the bones can have a supporting effect on the whole body. However, if calcium is deposited abnormally in the kidneys, calcified foci in the kidneys appear. Many kidney calcification foci are very much related to age, for example, older people are much more likely to find kidney calcification foci than younger people. Some calcified foci in the kidney may be kidney stones, especially in the central part of the kidney, the renal pelvis, which need to be treated actively because they may lead to recurrent pyelonephritis and also Kidney stones may lead to recurrent pyelonephritis, hydronephrosis, destruction of the kidney parenchyma, etc.