• Kidney calcification, more commonly known as kidney stones, is a condition in which the kidneys form small, hard deposits. These "stones" are made up of acid and mineral salts, and look like small rocks. They form for a number of reasons--often when the urine becomes highly concentrated, and the minerals are able to crystallize. Kidney stones can cause extreme back and side pain, though they rarely cause permanent damage.
  
  

Pain

• As kidney stones move into the tube connecting the bladder and kidney--the ureter--they can cause significant pain. This is usually located in the side and back, below the ribs, though it may spread into the groin and lower abdomen. Some people experience pain only when urinating, but others may experience it all the time. If the pain becomes too severe for you to sit still, is accompanied by a fever, or makes you nauseated, see a doctor right away.
  
  

Urinary Symptoms

• Kidney calcification also causes urinary symptoms. In addition to pain while urinating, people suffering from kidney stones may see brown, pink, or red urine, caused by irritation of the ureter, and feel a persistent, strong urge to urinate. This urge may not be accompanied by actual urine. The pressure of the kidney stone inside the ureter creates a false feeling of fullness in the bladder. Some people may have reduced urine or no urine at all.
  
  

Fever

• Kidney stones themselves are not likely to cause permanent damage despite the severe pain that comes with them. If an infection occurs along with kidney calcification, though, you might experience a fever or chills. This indicates a serious problem, and means you should see a doctor immediately. Drink plenty of liquids, especially during the day, and use antibiotic treatment as recommended by your doctor.
  
  

Uremia

• Kidney calcification often comes from eating high quantities of calcium-rich food but may also be a side effect of chronic kidney failure. In serious cases, this kidney problem may cause uremia--an increase in waste products in the blood. Uremia is characterized by nausea and vomiting, tiredness, confusion and even seizures. If any of these symptoms accompany other kidney stone symptoms, see a doctor immediately.