Possible diseases with calcified spots on the kidney are kidney stones, medullary spongy kidney or hyperparathyroidism. The kidneys do not usually calcify, calcium is mainly deposited in the bones, if calcium is deposited in the kidneys it is called a renal calcification spot. The most common cause of kidney calcification is kidney stones, mainly due to improper diet, such as eating too much food containing purine, oxalic acid and cystine. In addition, the kidney stones will be caused by poor exercise and low water intake, which will be shown in the kidney plain film or CT. The second is medullary spongy kidney, which is a congenital disease with a genetic predisposition, with many calcified spots in the medulla of the kidney. The second is hyperparathyroidism, mainly because the parathyroid gland regulates calcium and phosphorus imbalance. If hyperparathyroidism occurs, it can cause metastatic calcification, which transports calcium to the kidney and shows calcified spots.