Diagnosis of PSGN begins with the history and physical exam. A history of recent sore throat or skin infection and kidney problems suggests PSGN.
A urine test called a urinalysis is usually done. This test can show abnormal blood or protein in the urine. A blood test called an antibody titer may also be done. This test helps to confirm that a recent strep infection has occurred. Another blood test called a complement level is often abnormal in this condition. This test measures the activity of part of the immune system.
A person with unusual, prolonged, or severe symptoms may need a kidney biopsy. This procedure can help figure out the amount and type of kidney damage. It can also help make sure that there are no other conditions causing kidney damage.