What Causes Kidney Pain?
A kidney cyst is a fluid-filled pouch with a round shape that develops inside of or on the tissues of the kidney. Kidney cysts that do not occur as a part of polycystic kidney disease are referred to as simple kidney cysts. Some kidney cysts produce no symptoms at all, while others that have grown to larger sizes can cause kidney pain in the back, upper abdomen, and side. Severe kidney pain may be attributed to an infected or ruptured kidney cyst, or one blocking the healthy flow of the urine, causing hydronephrosis. Most kidney cysts form due to unknown causes, but surface pouches or diverticulum that fill with fluid have been implicated. Diagnostic imaging tests such as MRI and CT scans can identify and distinguish a kidney cyst from other conditions that may cause pain in the kidneys. Blood tests that measure an individual's kidney function can help a physician determine if a cyst is causing impairment in kidney function. Some kidney cysts do not require treatment, while others need to be drained with a needle or surgically removed.